1. Global warming is driven largely by atmospheric CO2 according to the concentration above its pre-industrial level; and
2. After emissions are stopped it could take millenia for the concentration to fall back to that level, because the effective lifetime of some of that excess CO2 is many thousands of years.
Therefore:
3. Drastic emissions reduction, even to zero overnight, cannot and will not stop the Arctic continuing to warm for decades.
Therefore:
4. The Arctic sea ice will continue to retreat, accelerating the warming due to the albedo effect.
Therefore:
5. The permafrost will continue to thaw releasing increasing quantities of methane, a potent greenhouse gas, potentially adding many degrees to global warming; and
6. The Greenland ice sheet will become increasingly unstable, potentially contributing to an eventual sea level rise of 7 metres.
Therefore:
7. To avoid these two catastrophes, we need to cool the Arctic quickly enough to save the Arctic sea ice; and
8. Probably the only feasible way to do this is through solar radiation management (SRM) geoengineering.
9. SRM is not a last resort, it is needed now to cool the Arctic.
It is incredible that people do not seem to follow this train of logic - it is so obvious.
Yet when I challenged a panel of geoengineering experts to refute this argument, the response was that geoengineering (even just to cool the Arctic) was too dangerous - not that the argument was false! [1]
So we continue to hear politicians and their advisers claiming that emissions reduction alone can be sufficient to keep the planet safe. [2]
And we continue to hear geoengineering experts saying that geoengineering should only be used as a last resort. [3]
How can this mindset be changed quickly, to avoid leaving geoengineering too late?
John
P.S. Apologies to those who have heard this all before and accept the logic as self-evident.
[1] This challenge was put to the panel at the launch of the Royal Society geoengineering report, on September 1st, with response from the team leader and panel chairman, Professor John Shepherd.
[2] For example at the geoengineering hearing at the House of Commons, November 2008.
[3] For example at the congressional hearing on geoengineering, November 2009.
I largely agree with your logical train of arguments. Except I'm not
convinced on #9 (NOW!). Given the well known risks (and unknown
ones!) of SRM, shouldn't CO2 reduction technologies be given a chance?
What's your evidence that applying SRM a decade from now will not be
sufficient to prevent a climate catastrophe? In a decade from now
SRMs may have matured & safer (on paper).
On Thu, Nov 12, 2009 at 5:51 PM, John Nissen <j...@cloudworld.co.uk> wrote:
> It is incredible. It is so obvious.
> 1. Global warming is driven largely by atmospheric CO2 according to the
> concentration above its pre-industrial level; and
> 2. After emissions are stopped it could take millenia for the
> concentration to fall back to that level, because the effective lifetime
> of some of that excess CO2 is many thousands of years.
> Therefore:
> 3. Drastic emissions reduction, even to zero overnight, cannot and will
> not stop the Arctic continuing to warm for decades.
> Therefore:
> 4. The Arctic sea ice will continue to retreat, accelerating the warming
> due to the albedo effect.
> Therefore:
> 5. The permafrost will continue to thaw releasing increasing quantities
> of methane, a potent greenhouse gas, potentially adding many degrees to
> global warming; and
> 6. The Greenland ice sheet will become increasingly unstable,
> potentially contributing to an eventual sea level rise of 7 metres.
> Therefore:
> 7. To avoid these two catastrophes, we need to cool the Arctic quickly
> enough to save the Arctic sea ice; and
> 8. Probably the only feasible way to do this is through solar radiation
> management (SRM) geoengineering.
> 9. SRM is not a last resort, it is needed now to cool the Arctic.
> It is incredible that people do not seem to follow this train of logic -
> it is so obvious.
> Yet when I challenged a panel of geoengineering experts to refute this
> argument, the response was that geoengineering (even just to cool the
> Arctic) was too dangerous - not that the argument was false! [1]
> So we continue to hear politicians and their advisers claiming that
> emissions reduction alone can be sufficient to keep the planet safe. [2]
> And we continue to hear geoengineering experts saying that
> geoengineering should only be used as a last resort. [3]
> How can this mindset be changed quickly, to avoid leaving geoengineering
> too late?
> John
> P.S. Apologies to those who have heard this all before and accept the
> logic as self-evident.
> [1] This challenge was put to the panel at the launch of the Royal
> Society geoengineering report, on September 1st, with response from the
> team leader and panel chairman, Professor John Shepherd.
> [2] For example at the geoengineering hearing at the House of Commons,
> November 2008.
> [3] For example at the congressional hearing on geoengineering, November
> 2009.
> --
> You received this message because you are subscribed to the Google Groups "geoengineering" group.
> To post to this group, send email to geoengineering@googlegroups.com.
> To unsubscribe from this group, send email to geoengineering+unsubscribe@googlegroups.com.
> For more options, visit this group at http://groups.google.com/group/geoengineering?hl=.
"Shouldn't CO2 reduction technologies be given a chance?" That is laughable.
Who is going to give CO2 reduction technologies a chance? Where will the
money come from to implement new technology on the scale needed to make a
difference. Where will the consensus come from? Russia and Canada will give
it lip service because they want the Arctic seaways open and they sell
fossil fuels.
In any case the cries of doom and gloom from the global warming advocates
especially in the absence of any credible science relating warming to CO2
levels is not going anywhere. This thing will drag on and on and Nero
fiddles while the world burns.
-----Original Message-----
From: Glyn Roberts [mailto:glynlrobe...@gmail.com] Sent: Thursday, November 12, 2009 6:17 PM
To: j...@cloudworld.co.uk
Cc: Geoengineering; Oliver Tickell
Subject: Re: [geo] Rejected - a simple argument for SRM geoengineering
I largely agree with your logical train of arguments. Except I'm not
convinced on #9 (NOW!). Given the well known risks (and unknown
ones!) of SRM, shouldn't CO2 reduction technologies be given a chance?
What's your evidence that applying SRM a decade from now will not be
sufficient to prevent a climate catastrophe? In a decade from now
SRMs may have matured & safer (on paper).
best regards,
Glyn
On Thu, Nov 12, 2009 at 5:51 PM, John Nissen <j...@cloudworld.co.uk> wrote:
> It is incredible. It is so obvious.
> 1. Global warming is driven largely by atmospheric CO2 according to the
> concentration above its pre-industrial level; and
> 2. After emissions are stopped it could take millenia for the
> concentration to fall back to that level, because the effective lifetime
> of some of that excess CO2 is many thousands of years.
> Therefore:
> 3. Drastic emissions reduction, even to zero overnight, cannot and will
> not stop the Arctic continuing to warm for decades.
> Therefore:
> 4. The Arctic sea ice will continue to retreat, accelerating the warming
> due to the albedo effect.
> Therefore:
> 5. The permafrost will continue to thaw releasing increasing quantities
> of methane, a potent greenhouse gas, potentially adding many degrees to
> global warming; and
> 6. The Greenland ice sheet will become increasingly unstable,
> potentially contributing to an eventual sea level rise of 7 metres.
> Therefore:
> 7. To avoid these two catastrophes, we need to cool the Arctic quickly
> enough to save the Arctic sea ice; and
> 8. Probably the only feasible way to do this is through solar radiation
> management (SRM) geoengineering.
> 9. SRM is not a last resort, it is needed now to cool the Arctic.
> It is incredible that people do not seem to follow this train of logic -
> it is so obvious.
> Yet when I challenged a panel of geoengineering experts to refute this
> argument, the response was that geoengineering (even just to cool the
> Arctic) was too dangerous - not that the argument was false! [1]
> So we continue to hear politicians and their advisers claiming that
> emissions reduction alone can be sufficient to keep the planet safe. [2]
> And we continue to hear geoengineering experts saying that
> geoengineering should only be used as a last resort. [3]
> How can this mindset be changed quickly, to avoid leaving geoengineering
> too late?
> John
> P.S. Apologies to those who have heard this all before and accept the
> logic as self-evident.
> [1] This challenge was put to the panel at the launch of the Royal
> Society geoengineering report, on September 1st, with response from the
> team leader and panel chairman, Professor John Shepherd.
> [2] For example at the geoengineering hearing at the House of Commons,
> November 2008.
> [3] For example at the congressional hearing on geoengineering, November
> 2009.
> --
> You received this message because you are subscribed to the Google Groups
"geoengineering" group.
> To post to this group, send email to geoengineering@googlegroups.com.
> To unsubscribe from this group, send email to
geoengineering+unsubscribe@googlegroups.com.
> For more options, visit this group at
http://groups.google.com/group/geoengineering?hl=.
--
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I suggest you are missing the point. The various countries are giving lip
service to reversing the global warming problem by reducing CO2 emissions or
by carbon capture. Copenhagen will produce nothing of substance. Moreover,
nothing significant will happen in the next 25 years. I agree that re-icing
the poles is critical and that can be done best or may only be feasible by
geoengineering in the short term. This group has been giving this serious
consideration for a considerable time. You are preaching to the choir. It is
not the thinking that is lacking but funding. Moreover, even if
anthropogenic CO2 emissions were brought to zero and some reversal of CO2
concentration were achieved, there is a reasonable argument that the planet
will continue to get warmer for other reasons. (That is an off topic
discussion.)
I would argue based on over 50 years of experience beyond my postdoc that
the experienced people, (or those with training and willing to shift focus)
will follow the money. The most critical need right now is to get a viable
source of long term funding, then attack the polar re-icing and let the
politicians deal with restructuring energy generation to reduce carbon
emissions.
From: Raymond Law [mailto:r2007...@gmail.com] Sent: Friday, November 13, 2009 6:45 AM
To: euggor...@comcast.net
Cc: glynlrobe...@gmail.com; j...@cloudworld.co.uk; Geoengineering; Oliver
Tickell
Subject: Re: [geo] Rejected - a simple argument for SRM geoengineering
Mr. John Nissen's train of logical thinking should really deserve serious
consideration by those politicians like Al Gore that are relevant with
reversing global warming. It is logical to consider all options,
short/quick term or long/slow term solutions, main stream or alternate ones
---- as long as they can do the job.
Politicians and big businesses generally prefer the main streams probably it
is the path of least resistance in getting enormous fundings. But alternate
ones could also create huge fundings needs too ; and alternate solutions
could be more dispersed/localized, meaning that it is easier to envisage the
creation of technology-transferred localized businesses and boosting
localized jobs/economies --- anyone cares to identify more opportunities
for politicians to work on. Lets face it, you might not like politicians,
but you really need them to turn your ideas into reality.
Your ' urgency ' direction is pointing to the one true and real need at
this juncture is to re-ice the poles. I think that we should pool our
brains together and give this direction serious thinking.
Raymond Law
On Fri, Nov 13, 2009 at 9:11 AM, Eugene I. Gordon <euggor...@comcast.net>
wrote:
"Shouldn't CO2 reduction technologies be given a chance?" That is laughable.
Who is going to give CO2 reduction technologies a chance? Where will the
money come from to implement new technology on the scale needed to make a
difference. Where will the consensus come from? Russia and Canada will give
it lip service because they want the Arctic seaways open and they sell
fossil fuels.
In any case the cries of doom and gloom from the global warming advocates
especially in the absence of any credible science relating warming to CO2
levels is not going anywhere. This thing will drag on and on and Nero
fiddles while the world burns.
-----Original Message-----
From: Glyn Roberts [mailto:glynlrobe...@gmail.com]
Sent: Thursday, November 12, 2009 6:17 PM
To: j...@cloudworld.co.uk
Cc: Geoengineering; Oliver Tickell
Subject: Re: [geo] Rejected - a simple argument for SRM geoengineering
I largely agree with your logical train of arguments. Except I'm not
convinced on #9 (NOW!). Given the well known risks (and unknown
ones!) of SRM, shouldn't CO2 reduction technologies be given a chance?
What's your evidence that applying SRM a decade from now will not be
sufficient to prevent a climate catastrophe? In a decade from now
SRMs may have matured & safer (on paper).
best regards,
Glyn
On Thu, Nov 12, 2009 at 5:51 PM, John Nissen <j...@cloudworld.co.uk> wrote:
> It is incredible. It is so obvious.
> 1. Global warming is driven largely by atmospheric CO2 according to the
> concentration above its pre-industrial level; and
> 2. After emissions are stopped it could take millenia for the
> concentration to fall back to that level, because the effective lifetime
> of some of that excess CO2 is many thousands of years.
> Therefore:
> 3. Drastic emissions reduction, even to zero overnight, cannot and will
> not stop the Arctic continuing to warm for decades.
> Therefore:
> 4. The Arctic sea ice will continue to retreat, accelerating the warming
> due to the albedo effect.
> Therefore:
> 5. The permafrost will continue to thaw releasing increasing quantities
> of methane, a potent greenhouse gas, potentially adding many degrees to
> global warming; and
> 6. The Greenland ice sheet will become increasingly unstable,
> potentially contributing to an eventual sea level rise of 7 metres.
> Therefore:
> 7. To avoid these two catastrophes, we need to cool the Arctic quickly
> enough to save the Arctic sea ice; and
> 8. Probably the only feasible way to do this is through solar radiation
> management (SRM) geoengineering.
> 9. SRM is not a last resort, it is needed now to cool the Arctic.
> It is incredible that people do not seem to follow this train of logic -
> it is so obvious.
> Yet when I challenged a panel of geoengineering experts to refute this
> argument, the response was that geoengineering (even just to cool the
> Arctic) was too dangerous - not that the argument was false! [1]
> So we continue to hear politicians and their advisers claiming that
> emissions reduction alone can be sufficient to keep the planet safe. [2]
> And we continue to hear geoengineering experts saying that
> geoengineering should only be used as a last resort. [3]
> How can this mindset be changed quickly, to avoid leaving geoengineering
> too late?
> John
> P.S. Apologies to those who have heard this all before and accept the
> logic as self-evident.
> [1] This challenge was put to the panel at the launch of the Royal
> Society geoengineering report, on September 1st, with response from the
> team leader and panel chairman, Professor John Shepherd.
> [2] For example at the geoengineering hearing at the House of Commons,
> November 2008.
> [3] For example at the congressional hearing on geoengineering, November
> 2009.
> --
> You received this message because you are subscribed to the Google Groups
"geoengineering" group.
> To post to this group, send email to geoengineering@googlegroups.com.
> To unsubscribe from this group, send email to
geoengineering+unsubscribe@googlegroups.com
<mailto:geoengineering%2Bunsubscribe@googlegroups.com> .
> For more options, visit this group at
http://groups.google.com/group/geoengineering?hl=.
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Mr. John Nissen's train of logical thinking should really deserve serious
consideration by those politicians like Al Gore that are relevant with
reversing global warming. It is logical to consider all options,
short/quick term or long/slow term solutions, main stream or alternate ones
---- as long as they can do the job.
Politicians and big businesses generally prefer the main streams probably it
is the path of least resistance in getting enormous fundings. But alternate
ones could also create huge fundings needs too ; and alternate
solutions could be more dispersed/localized, meaning that it is easier to
envisage the creation of technology-transferred localized businesses and
boosting localized jobs/economies --- anyone cares to identify more
opportunities for politicians to work on. Lets face it, you might not like
politicians, but you really need them to turn your ideas into reality.
Your ' urgency ' direction is pointing to the one true and real need at
this juncture is to re-ice the poles. I think that we should pool our
brains together and give this direction serious thinking.
*Raymond Law*
On Fri, Nov 13, 2009 at 9:11 AM, Eugene I. Gordon <euggor...@comcast.net>wrote:
> "Shouldn't CO2 reduction technologies be given a chance?" That is
> laughable.
> Who is going to give CO2 reduction technologies a chance? Where will the
> money come from to implement new technology on the scale needed to make a
> difference. Where will the consensus come from? Russia and Canada will give
> it lip service because they want the Arctic seaways open and they sell
> fossil fuels.
> In any case the cries of doom and gloom from the global warming advocates
> especially in the absence of any credible science relating warming to CO2
> levels is not going anywhere. This thing will drag on and on and Nero
> fiddles while the world burns.
> -gene
> -----Original Message-----
> From: Glyn Roberts [mailto:glynlrobe...@gmail.com]
> Sent: Thursday, November 12, 2009 6:17 PM
> To: j...@cloudworld.co.uk
> Cc: Geoengineering; Oliver Tickell
> Subject: Re: [geo] Rejected - a simple argument for SRM geoengineering
> I largely agree with your logical train of arguments. Except I'm not
> convinced on #9 (NOW!). Given the well known risks (and unknown
> ones!) of SRM, shouldn't CO2 reduction technologies be given a chance?
> What's your evidence that applying SRM a decade from now will not be
> sufficient to prevent a climate catastrophe? In a decade from now
> SRMs may have matured & safer (on paper).
> best regards,
> Glyn
> On Thu, Nov 12, 2009 at 5:51 PM, John Nissen <j...@cloudworld.co.uk> wrote:
> > It is incredible. It is so obvious.
> > 1. Global warming is driven largely by atmospheric CO2 according to the
> > concentration above its pre-industrial level; and
> > 2. After emissions are stopped it could take millenia for the
> > concentration to fall back to that level, because the effective lifetime
> > of some of that excess CO2 is many thousands of years.
> > Therefore:
> > 3. Drastic emissions reduction, even to zero overnight, cannot and will
> > not stop the Arctic continuing to warm for decades.
> > Therefore:
> > 4. The Arctic sea ice will continue to retreat, accelerating the warming
> > due to the albedo effect.
> > Therefore:
> > 5. The permafrost will continue to thaw releasing increasing quantities
> > of methane, a potent greenhouse gas, potentially adding many degrees to
> > global warming; and
> > 6. The Greenland ice sheet will become increasingly unstable,
> > potentially contributing to an eventual sea level rise of 7 metres.
> > Therefore:
> > 7. To avoid these two catastrophes, we need to cool the Arctic quickly
> > enough to save the Arctic sea ice; and
> > 8. Probably the only feasible way to do this is through solar radiation
> > management (SRM) geoengineering.
> > 9. SRM is not a last resort, it is needed now to cool the Arctic.
> > It is incredible that people do not seem to follow this train of logic -
> > it is so obvious.
> > Yet when I challenged a panel of geoengineering experts to refute this
> > argument, the response was that geoengineering (even just to cool the
> > Arctic) was too dangerous - not that the argument was false! [1]
> > So we continue to hear politicians and their advisers claiming that
> > emissions reduction alone can be sufficient to keep the planet safe. [2]
> > And we continue to hear geoengineering experts saying that
> > geoengineering should only be used as a last resort. [3]
> > How can this mindset be changed quickly, to avoid leaving geoengineering
> > too late?
> > John
> > P.S. Apologies to those who have heard this all before and accept the
> > logic as self-evident.
> > [1] This challenge was put to the panel at the launch of the Royal
> > Society geoengineering report, on September 1st, with response from the
> > team leader and panel chairman, Professor John Shepherd.
> > [2] For example at the geoengineering hearing at the House of Commons,
> > November 2008.
> > [3] For example at the congressional hearing on geoengineering, November
> > 2009.
> > --
> > You received this message because you are subscribed to the Google Groups
> "geoengineering" group.
> > To post to this group, send email to geoengineering@googlegroups.com.
> > To unsubscribe from this group, send email to
> geoengineering+unsubscribe@googlegroups.com<geoengineering%2Bunsubscribe@go oglegroups.com>
> .
> > For more options, visit this group at
> http://groups.google.com/group/geoengineering?hl=.
> --
> You received this message because you are subscribed to the Google Groups
> "geoengineering" group.
> To post to this group, send email to geoengineering@googlegroups.com.
> To unsubscribe from this group, send email to
> geoengineering+unsubscribe@googlegroups.com<geoengineering%2Bunsubscribe@go oglegroups.com>
> .
> For more options, visit this group at
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> --
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> "geoengineering" group.
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> To unsubscribe from this group, send email to
> geoengineering+unsubscribe@googlegroups.com<geoengineering%2Bunsubscribe@go oglegroups.com>
> .
> For more options, visit this group at
> http://groups.google.com/group/geoengineering?hl=.
And Raymond Law is not missing the point. He has followed my chain of
reasoning, concerning the critical situation in the Arctic (and it's
critical in Antarctic also). This reasoning has been accepted by many
of us in the group - yet when the Royal Society produced its
geoengineering report, and when there was the subsequent Congressional
hearing on geoengineering, the need for geoengineering to cool the
Arctic was not mentioned. I know for certain it was deliberately
ignored in the former case, and it could have been deliberate in the
latter. I suspect that the academics who want to be seen as leading
lights on geoengineering are scared to look too enthusiastic about
geoengineering, so suggest there may be enormous dangers. As Gregory
Benford said, in immediate response to my original posting:
"YET the dangers aren't studied, and in fact are probably small.
Yes: cowards. No other word for it."
Cowardice will get us nowhere. We need a bold plan to save
civilisation, such as Lester R Brown's "Plan B" [1], nicely explained
here [2], or Oliver Tickell's Kyoto2 [3]. But such a plan does need to
include SRM geoengineering for saving the Arctic sea ice. Can anybody
argue with the logic?
I
suggest you are missing the point. The various countries are
giving lip service to reversing the global warming problem by reducing
CO2
emissions or by carbon capture. Copenhagen will produce nothing of
substance.
Moreover, nothing significant will happen in the next 25 years. I
agree
that re-icing the poles is critical and that can be done best or may
only be
feasible by geoengineering in the short term. This group has been
giving this
serious consideration for a considerable time. You are preaching to the
choir. It
is not the thinking that is lacking but funding. Moreover, even if
anthropogenic
CO2 emissions were brought to zero and some reversal of CO2
concentration were achieved,
there is a reasonable argument that the planet will continue to get
warmer for other
reasons. (That is an off topic discussion.)
I
would argue based on over 50 years of experience beyond my
postdoc that the experienced people, (or those with training and
willing to shift
focus) will follow the money. The most critical need right now is to
get a
viable source of long term funding, then attack the polar re-icing and
let the
politicians deal with restructuring energy generation to reduce carbon
emissions.
Mr. John Nissen's train of logical thinking
should really
deserve serious consideration by those politicians like Al Gore that
are
relevant with reversing global warming. It is logical to consider all
options, short/quick term or long/slow term solutions, main stream or
alternate
ones ---- as long as they can do the job.
Politicians and big businesses generally prefer
the main
streams probably it is the path of least resistance in getting enormous
fundings. But alternate ones could also create huge fundings needs
too ; and alternate solutions could be more dispersed/localized,
meaning that it is easier to envisage the creation of
technology-transferred
localized businesses and boosting localized jobs/economies ---
anyone cares to identify more opportunities for politicians to work
on.
Lets face it, you might not like politicians, but you really need them
to turn
your ideas into reality.
Your ' urgency ' direction is pointing to the
one true and real need at this juncture is to re-ice the poles. I
think
that we should pool our brains together and give this direction serious
thinking.
Hi Eugene and everyone else. Do you mean funding for studying the
greenhouse effect and geoengineering projects or funding for
geoengineering projects themselves. Or funding for conventional
projects like solar nergy and other renewable substitutes to replace
oil and coal? I agree with Greg Benford that cowardice is a major
reason that geonegineering has been given short shrift despite its
importance.
Here's some ideas I've had that might be new or might not be.
1.) Instead of fertilizing parts of the ocean with low iron levels we
can build pipelines form iron rich parts of the ocean and transport
iron laden waters to surface of iron poor regions. A pipeline will
provide a steady source of nutrients and it can be powered by wave
enrgy or OTEC which will move water from lower depths to higher
deaths. It will cost less also since iron mined on the land can run
out and it will become increasing scarce.
2.) Collecting Sargasso sea seaweed and burning it in generator plants
or converting it to ethanol, methanol etc and using it as a renewable
resource is possible. The minerals in the seaweed can be recycled back
into the Sargasso sea.
3.) Providing iron and nutrients to seaweed in the Sargasso sea might
remove as much or more CO2 from the atmosphere than fertilizing iron
poor parts of the ocean. Redistributing some of the iron laden water
in the Sargasso sea to parts of the ocean near the Sargasso sea might
cause more seaweed to grow if optimal concentrations of nutrients are
provided. That is different than causing upwellings from the bottom of
the ocean. vertical pipelines from nutrient laden waters under the
kelp can transport water to parts near the seaweed to cause additional
growth. Spreading the nutrients to surrounding water might cause more
seaweed to grow.
On Nov 13, 11:48 am, John Nissen <j...@cloudworld.co.uk> wrote:
> Hi Eugene,
> Money isn't the problem. Cowardice more like.
> And Raymond Law is not missing the point. He has followed my chain of reasoning, concerning the critical situation in the Arctic (and it's critical in Antarctic also). This reasoning has been accepted by many of us in the group - yet when the Royal Society produced its geoengineering report, and when there was the subsequent Congressional hearing on geoengineering, the need for geoengineering to cool the Arctic was not mentioned. I know for certain it was deliberately ignored in the former case, and it could have been deliberate in the latter. I suspect that the academics who want to be seen as leading lights on geoengineering are scared to look too enthusiastic about geoengineering, so suggest there may be enormous dangers. As Gregory Benford said, in immediate response to my original posting:
> "YET the dangers aren't studied, and in fact are probably small. Yes: cowards. No other word for it."
> Cowardice will get us nowhere. We need a bold plan to save civilisation, such as Lester R Brown's "Plan B" [1], nicely explained here [2], or Oliver Tickell's Kyoto2 [3]. But such a plan does need to include SRM geoengineering for saving the Arctic sea ice. Can anybody argue with the logic?
> Cheers,
> John
> [1] Plan B, version 4.0http://www.earth-policy.org/index.php?/books/pb4/pb4_table_of_contents > [2] Scientific American, May 2009:http://www.scientificamerican.com/article.cfm?id=civilization-food-sh... > [3] Kyoto2 leaflet. See attached
> --
> Eugene I. Gordon wrote:
> Dear Mr. Law:
>
> I suggest you are missing the point. The various countries are giving lip service to reversing the global warming problem by reducing CO2 emissions or by carbon capture. Copenhagen will produce nothing of substance. Moreover, nothing significant will happen in the next 25 years. I agree that re-icing the poles is critical and that can be done best or may only be feasible by geoengineering in the short term. This group has been giving this serious consideration for a considerable time. You are preaching to the choir. It is not the thinking that is lacking but funding. Moreover, even if anthropogenic CO2 emissions were brought to zero and some reversal of CO2 concentration were achieved, there is a reasonable argument that the planet will continue to get warmer for other reasons. (That is an off topic discussion.)
>
> I would argue based on over 50 years of experience beyond my postdoc that the experienced people, (or those with training and willing to shift focus) will follow the money. The most critical need right now is to get a viable source of long term funding, then attack the polar re-icing and let the politicians deal with restructuring energy generation to reduce carbon emissions.
> From:Raymond Law [mailto:r2007...@gmail.com]Sent:Friday, November 13, 2009 6:45 AMTo:euggor...@comcast.netCc:glynlrobe...@gmail.com;j...@cloudworld.co.uk; Geoengineering; Oliver TickellSubject:Re: [geo] Rejected - a simple argument for SRM geoengineering
>
> Mr. John Nissen's train of logical thinking should really deserve serious consideration by those politicians like Al Gore that are relevant with reversing global warming. It is logical to consider all options, short/quick term or long/slow term solutions, main stream or alternate ones ---- as long as they can do the job.
>
> Politicians and big businesses generally prefer the main streams probably it is the path of least resistance in getting enormous fundings. But alternate ones could also create huge fundings needs too ; and alternate solutions could be more dispersed/localized, meaning that it is easier to envisage the creation of technology-transferred localized businesses and boosting localized jobs/economies --- anyone cares to identify more opportunities for politicians to work on. Lets face it, you might not like politicians, but you really need them to turn your ideas into reality.
>
> Your ' urgency ' direction is pointing to the one true and real need at this juncture is to re-ice the poles. I think that we should pool our brains together and give this direction serious thinking.
Nice one, John; the train of argument is clear (of limpid clarity, in
fact!) The problem is that the people and institutions addressed are
in the business of politics, the art of the possible, rather than in
the business of logical evaluation. They hear what you are saying and
must see the validity of it. But politically what is true and what is
doable do not always coincide, as we all know from as many examples as
one cares to ennumerate.
We have to keep hammering away at the arguments, to the point at which
they are generally understood and accepted, and also keep on
politicking in the sure and certain hope that eventually the
acceptance of the arguments and the cowardice/caution/horse sense/
opportunistic careerism of the politicos will achieve the right kind
of intersection. In the next year or so (& wouldn't it be a great
help to have the environmental NGOs on board.)
On Nov 12, 10:51 pm, John Nissen <j...@cloudworld.co.uk> wrote:
> 1. Global warming is driven largely by atmospheric CO2 according to the
> concentration above its pre-industrial level; and
> 2. After emissions are stopped it could take millenia for the
> concentration to fall back to that level, because the effective lifetime
> of some of that excess CO2 is many thousands of years.
> Therefore:
> 3. Drastic emissions reduction, even to zero overnight, cannot and will
> not stop the Arctic continuing to warm for decades.
> Therefore:
> 4. The Arctic sea ice will continue to retreat, accelerating the warming
> due to the albedo effect.
> Therefore:
> 5. The permafrost will continue to thaw releasing increasing quantities
> of methane, a potent greenhouse gas, potentially adding many degrees to
> global warming; and
> 6. The Greenland ice sheet will become increasingly unstable,
> potentially contributing to an eventual sea level rise of 7 metres.
> Therefore:
> 7. To avoid these two catastrophes, we need to cool the Arctic quickly
> enough to save the Arctic sea ice; and
> 8. Probably the only feasible way to do this is through solar radiation
> management (SRM) geoengineering.
> 9. SRM is not a last resort, it is needed now to cool the Arctic.
> It is incredible that people do not seem to follow this train of logic -
> it is so obvious.
> Yet when I challenged a panel of geoengineering experts to refute this
> argument, the response was that geoengineering (even just to cool the
> Arctic) was too dangerous - not that the argument was false! [1]
> So we continue to hear politicians and their advisers claiming that
> emissions reduction alone can be sufficient to keep the planet safe. [2]
> And we continue to hear geoengineering experts saying that
> geoengineering should only be used as a last resort. [3]
> How can this mindset be changed quickly, to avoid leaving geoengineering
> too late?
> John
> P.S. Apologies to those who have heard this all before and accept the
> logic as self-evident.
> [1] This challenge was put to the panel at the launch of the Royal
> Society geoengineering report, on September 1st, with response from the
> team leader and panel chairman, Professor John Shepherd.
> [2] For example at the geoengineering hearing at the House of Commons,
> November 2008.
> [3] For example at the congressional hearing on geoengineering, November
> 2009.
At present the likely methane excursion is far from clear. Further, it is
also unclear how quickly the total excursion will occur. The excursion rate
is highly significant due to the short life of methane in the atmosphere.
The methane ends up as CO2, in itself a major issue. However, the CO2's
likely effect is nothing compared to the devastating temperature spike which
may result from a sudden methane excursion.
I don't oppose John's argument, but the evidence on the severity of the
problem is far from conclusive. We need much more research into:
1) The methane reservoir in clathrates and permafrost
2) The size of potential methane sources currently frozen as organic
detritus
3) The likely changes to the GWP of methane in future atmospheres, as the
levels of hydroxyl radicals etc. shift over time and as a direct result of
methane excursion. Recent research on this asks more questions than it
answers.
My personal feeling is that the range of likely outcomes is from a
significant amplification of AGW, right up to a 'Great Dying' sized
mass-extinction event when we come within a sneeze of sterilising the entire
planet. I'd be tempted to bet on the latter, but I wouldn't be around to
collect the winnings, so I'll keep my wallet in my pocket.
My suggestions is that geoengineers look at ways to clean up the methane
from the atmosphere, and then lock down the resulting carbon. My guess is
we've got about 50 years to do this, but virtually no time at all if the
methane can't be dealt with once it's in the atmosphere. Therefore, I'd
support John out of precautionary principle-based reasoning.
A
2009/11/15 jim woolridge <jimwoolri...@hotmail.com>
> Nice one, John; the train of argument is clear (of limpid clarity, in
> fact!) The problem is that the people and institutions addressed are
> in the business of politics, the art of the possible, rather than in
> the business of logical evaluation. They hear what you are saying and
> must see the validity of it. But politically what is true and what is
> doable do not always coincide, as we all know from as many examples as
> one cares to ennumerate.
> We have to keep hammering away at the arguments, to the point at which
> they are generally understood and accepted, and also keep on
> politicking in the sure and certain hope that eventually the
> acceptance of the arguments and the cowardice/caution/horse sense/
> opportunistic careerism of the politicos will achieve the right kind
> of intersection. In the next year or so (& wouldn't it be a great
> help to have the environmental NGOs on board.)
> On Nov 12, 10:51 pm, John Nissen <j...@cloudworld.co.uk> wrote:
> > It is incredible. It is so obvious.
> > 1. Global warming is driven largely by atmospheric CO2 according to the
> > concentration above its pre-industrial level; and
> > 2. After emissions are stopped it could take millenia for the
> > concentration to fall back to that level, because the effective lifetime
> > of some of that excess CO2 is many thousands of years.
> > Therefore:
> > 3. Drastic emissions reduction, even to zero overnight, cannot and will
> > not stop the Arctic continuing to warm for decades.
> > Therefore:
> > 4. The Arctic sea ice will continue to retreat, accelerating the warming
> > due to the albedo effect.
> > Therefore:
> > 5. The permafrost will continue to thaw releasing increasing quantities
> > of methane, a potent greenhouse gas, potentially adding many degrees to
> > global warming; and
> > 6. The Greenland ice sheet will become increasingly unstable,
> > potentially contributing to an eventual sea level rise of 7 metres.
> > Therefore:
> > 7. To avoid these two catastrophes, we need to cool the Arctic quickly
> > enough to save the Arctic sea ice; and
> > 8. Probably the only feasible way to do this is through solar radiation
> > management (SRM) geoengineering.
> > 9. SRM is not a last resort, it is needed now to cool the Arctic.
> > It is incredible that people do not seem to follow this train of logic -
> > it is so obvious.
> > Yet when I challenged a panel of geoengineering experts to refute this
> > argument, the response was that geoengineering (even just to cool the
> > Arctic) was too dangerous - not that the argument was false! [1]
> > So we continue to hear politicians and their advisers claiming that
> > emissions reduction alone can be sufficient to keep the planet safe. [2]
> > And we continue to hear geoengineering experts saying that
> > geoengineering should only be used as a last resort. [3]
> > How can this mindset be changed quickly, to avoid leaving geoengineering
> > too late?
> > John
> > P.S. Apologies to those who have heard this all before and accept the
> > logic as self-evident.
> > [1] This challenge was put to the panel at the launch of the Royal
> > Society geoengineering report, on September 1st, with response from the
> > team leader and panel chairman, Professor John Shepherd.
> > [2] For example at the geoengineering hearing at the House of Commons,
> > November 2008.
> > [3] For example at the congressional hearing on geoengineering, November
> > 2009.
> --
> You received this message because you are subscribed to the Google Groups
> "geoengineering" group.
> To post to this group, send email to geoengineering@googlegroups.com.
> To unsubscribe from this group, send email to
> geoengineering+unsubscribe@googlegroups.com<geoengineering%2Bunsubscribe@go oglegroups.com>
> .
> For more options, visit this group at
> http://groups.google.com/group/geoengineering?hl=.
Based on prior behavior I guess we might get 50 years of few or no sunspots.
Hence we might have 50 years before it gets really hot. In the meantime my
guess is that the Canadians and Russians will fight any attempt at Arctic
geoengineering to cool or get rid of CH4. Methane conversion to CO2 is one
molecule for one molecule; and CH4 is a more effective greenhouse gas so I
don't see methane conversion to CO2 as a big deal. The main converters are
OH and O2H radicals formed from O3 and H2O. So means of enhancing radical
formation would be desirable. Another way would be to introduce H2. All of
these conversion processes are at the expense of the ozone layer.
-gene
From: Andrew Lockley [mailto:andrew.lock...@gmail.com] Sent: Sunday, November 15, 2009 8:41 AM
To: geoengineering
Subject: Re: [geo] Re: Rejected - a simple argument for SRM geoengineering
At present the likely methane excursion is far from clear. Further, it is
also unclear how quickly the total excursion will occur. The excursion rate
is highly significant due to the short life of methane in the atmosphere.
The methane ends up as CO2, in itself a major issue. However, the CO2's
likely effect is nothing compared to the devastating temperature spike which
may result from a sudden methane excursion.
I don't oppose John's argument, but the evidence on the severity of the
problem is far from conclusive. We need much more research into:
1) The methane reservoir in clathrates and permafrost
2) The size of potential methane sources currently frozen as organic
detritus
3) The likely changes to the GWP of methane in future atmospheres, as the
levels of hydroxyl radicals etc. shift over time and as a direct result of
methane excursion. Recent research on this asks more questions than it
answers.
My personal feeling is that the range of likely outcomes is from a
significant amplification of AGW, right up to a 'Great Dying' sized
mass-extinction event when we come within a sneeze of sterilising the entire
planet. I'd be tempted to bet on the latter, but I wouldn't be around to
collect the winnings, so I'll keep my wallet in my pocket.
My suggestions is that geoengineers look at ways to clean up the methane
from the atmosphere, and then lock down the resulting carbon. My guess is
we've got about 50 years to do this, but virtually no time at all if the
methane can't be dealt with once it's in the atmosphere. Therefore, I'd
support John out of precautionary principle-based reasoning.
A
2009/11/15 jim woolridge <jimwoolri...@hotmail.com>
Nice one, John; the train of argument is clear (of limpid clarity, in
fact!) The problem is that the people and institutions addressed are
in the business of politics, the art of the possible, rather than in
the business of logical evaluation. They hear what you are saying and
must see the validity of it. But politically what is true and what is
doable do not always coincide, as we all know from as many examples as
one cares to ennumerate.
We have to keep hammering away at the arguments, to the point at which
they are generally understood and accepted, and also keep on
politicking in the sure and certain hope that eventually the
acceptance of the arguments and the cowardice/caution/horse sense/
opportunistic careerism of the politicos will achieve the right kind
of intersection. In the next year or so (& wouldn't it be a great
help to have the environmental NGOs on board.)
On Nov 12, 10:51 pm, John Nissen <j...@cloudworld.co.uk> wrote:
> 1. Global warming is driven largely by atmospheric CO2 according to the
> concentration above its pre-industrial level; and
> 2. After emissions are stopped it could take millenia for the
> concentration to fall back to that level, because the effective lifetime
> of some of that excess CO2 is many thousands of years.
> Therefore:
> 3. Drastic emissions reduction, even to zero overnight, cannot and will
> not stop the Arctic continuing to warm for decades.
> Therefore:
> 4. The Arctic sea ice will continue to retreat, accelerating the warming
> due to the albedo effect.
> Therefore:
> 5. The permafrost will continue to thaw releasing increasing quantities
> of methane, a potent greenhouse gas, potentially adding many degrees to
> global warming; and
> 6. The Greenland ice sheet will become increasingly unstable,
> potentially contributing to an eventual sea level rise of 7 metres.
> Therefore:
> 7. To avoid these two catastrophes, we need to cool the Arctic quickly
> enough to save the Arctic sea ice; and
> 8. Probably the only feasible way to do this is through solar radiation
> management (SRM) geoengineering.
> 9. SRM is not a last resort, it is needed now to cool the Arctic.
> It is incredible that people do not seem to follow this train of logic -
> it is so obvious.
> Yet when I challenged a panel of geoengineering experts to refute this
> argument, the response was that geoengineering (even just to cool the
> Arctic) was too dangerous - not that the argument was false! [1]
> So we continue to hear politicians and their advisers claiming that
> emissions reduction alone can be sufficient to keep the planet safe. [2]
> And we continue to hear geoengineering experts saying that
> geoengineering should only be used as a last resort. [3]
> How can this mindset be changed quickly, to avoid leaving geoengineering
> too late?
> John
> P.S. Apologies to those who have heard this all before and accept the
> logic as self-evident.
> [1] This challenge was put to the panel at the launch of the Royal
> Society geoengineering report, on September 1st, with response from the
> team leader and panel chairman, Professor John Shepherd.
> [2] For example at the geoengineering hearing at the House of Commons,
> November 2008.
> [3] For example at the congressional hearing on geoengineering, November
> 2009.
--
You received this message because you are subscribed to the Google Groups
"geoengineering" group.
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You say: "I don't oppose John's argument, but the evidence on the
severity of the problem is far from conclusive." I disagree.
The methane presents a very real risk - because of the uncertainty on
timing combined with the potential size of methane discharge - perhaps
even enough to cause thermal runaway due to positive feedback, as is
thought to have happened in the past [1]. Risk management involves
identifying events and assessing them in terms of their likelihood and
magnitude of impact [2]. Thus something with a small likelihood (such
as rapid massive methane excursion) can have a high risk, if the
magnitude of impact is sufficiently large (and you can't get much
larger than thermal runaway).
It is possible that much or most of the methane trapped in frozen
structures has built up over hundreds of thousands of years. There is
little sign of massive methane discharge in the ice record. In fact
methane seems to track the temperature even better than CO2 [3].
But of course methane discharge is not the only high risk event - there
is also the Greenland ice sheet disintegration.
BTW, does anybody know the _immediate_ warming potential of methane, as
opposed to the 20 year value (72), 100 years (25) or 500 years (7.6)?
The lifetime is only 12 +/- 3 years. See [4].
At present the likely methane excursion is far from clear.
Further, it is also unclear how quickly the total excursion will
occur. The excursion rate is highly significant due to the short life
of methane in the atmosphere. The methane ends up as CO2, in itself a
major issue. However, the CO2's likely effect is nothing compared to
the devastating temperature spike which may result from a sudden
methane excursion.
I don't oppose John's argument, but the evidence on the severity
of the problem is far from conclusive. We need much more research into:
1) The methane reservoir in clathrates and permafrost
2) The size of potential methane sources currently frozen as
organic detritus
3) The likely changes to the GWP of methane in future
atmospheres, as the levels of hydroxyl radicals etc. shift over time
and as a direct result of methane excursion. Recent research on this
asks more questions than it answers.
My personal feeling is that the range of likely outcomes is from
a significant amplification of AGW, right up to a 'Great Dying' sized
mass-extinction event when we come within a sneeze of sterilising the
entire planet. I'd be tempted to bet on the latter, but I wouldn't be
around to collect the winnings, so I'll keep my wallet in my pocket.
My suggestions is that geoengineers look at ways to clean up the
methane from the atmosphere, and then lock down the resulting carbon.
My guess is we've got about 50 years to do this, but virtually no time
at all if the methane can't be dealt with once it's in the atmosphere.
Therefore, I'd support John out of precautionary principle-based
reasoning.
Nice
one, John; the train of argument is clear (of limpid clarity, in
fact!) The problem is that the people and institutions addressed are
in the business of politics, the art of the possible, rather than in
the business of logical evaluation. They hear what you are saying and
must see the validity of it. But politically what is true and what is
doable do not always coincide, as we all know from as many examples as
one cares to ennumerate.
We have to keep hammering away at the arguments, to the point at which
they are generally understood and accepted, and also keep on
politicking in the sure and certain hope that eventually the
acceptance of the arguments and the cowardice/caution/horse sense/
opportunistic careerism of the politicos will achieve the right kind
of intersection. In the next year or so (& wouldn't it be a great
help to have the environmental NGOs on board.)
On Nov 12, 10:51 pm, John Nissen <j...@cloudworld.co.uk>
wrote:
> It is incredible. It is so obvious.
>
> 1. Global warming is driven largely by atmospheric CO2 according
to the
> concentration above its pre-industrial level; and
>
> 2. After emissions are stopped it could take millenia for the
> concentration to fall back to that level, because the effective
lifetime
> of some of that excess CO2 is many thousands of years.
>
> Therefore:
> 3. Drastic emissions reduction, even to zero overnight, cannot
and will
> not stop the Arctic continuing to warm for decades.
>
> Therefore:
> 4. The Arctic sea ice will continue to retreat, accelerating the
warming
> due to the albedo effect.
>
> Therefore:
> 5. The permafrost will continue to thaw releasing increasing
quantities
> of methane, a potent greenhouse gas, potentially adding many
degrees to
> global warming; and
>
> 6. The Greenland ice sheet will become increasingly unstable,
> potentially contributing to an eventual sea level rise of 7 metres.
>
> Therefore:
> 7. To avoid these two catastrophes, we need to cool the Arctic
quickly
> enough to save the Arctic sea ice; and
>
> 8. Probably the only feasible way to do this is through solar
radiation
> management (SRM) geoengineering.
>
> 9. SRM is not a last resort, it is needed now to cool the Arctic.
>
> It is incredible that people do not seem to follow this train of
logic -
> it is so obvious.
>
> Yet when I challenged a panel of geoengineering experts to refute
this
> argument, the response was that geoengineering (even just to cool
the
> Arctic) was too dangerous - not that the argument was false! [1]
>
> So we continue to hear politicians and their advisers claiming that
> emissions reduction alone can be sufficient to keep the planet
safe. [2]
>
> And we continue to hear geoengineering experts saying that
> geoengineering should only be used as a last resort. [3]
>
> How can this mindset be changed quickly, to avoid leaving
geoengineering
> too late?
>
> John
>
> P.S. Apologies to those who have heard this all before and accept
the
> logic as self-evident.
>
> [1] This challenge was put to the panel at the launch of the Royal
> Society geoengineering report, on September 1st, with response
from the
> team leader and panel chairman, Professor John Shepherd.
>
> [2] For example at the geoengineering hearing at the House of
Commons,
> November 2008.
>
> [3] For example at the congressional hearing on geoengineering,
November
> 2009.
You received this message because you are subscribed to the Google
Groups "geoengineering" group.
To post to this group, send email to geoengineering@googlegroups.com.
To unsubscribe from this group, send email to
You say: "I don't oppose John's argument, but the evidence on the
severity of the problem is far from conclusive." I disagree.
The methane presents a very real risk - because of the uncertainty on
timing combined with the potential size of methane discharge - perhaps
even enough to cause thermal runaway due to positive feedback, as is
thought to have happened in the past [1]. Risk management involves
identifying events and assessing them in terms of their likelihood and
magnitude of impact [2]. Thus something with a small likelihood (such
as rapid massive methane excursion) can have a high risk, if the
magnitude of impact is sufficiently large (and you can't get much
larger than thermal runaway).
It is possible that much or most of the methane trapped in frozen
structures has built up over hundreds of thousands of years. There is
little sign of massive methane discharge in the ice record. In fact
methane seems to track the temperature even better than CO2 [3].
But of course methane discharge is not the only high risk event - there
is also the Greenland ice sheet disintegration.
BTW, does anybody know the _immediate_ warming potential of methane, as
opposed to the 20 year value (72), 100 years (25) or 500 years (7.6)?
The lifetime is only 12 +/- 3 years. See [4].
At present the likely methane excursion is far from clear.
Further, it is also unclear how quickly the total excursion will
occur. The excursion rate is highly significant due to the short life
of methane in the atmosphere. The methane ends up as CO2, in itself a
major issue. However, the CO2's likely effect is nothing compared to
the devastating temperature spike which may result from a sudden
methane excursion.
I don't oppose John's argument, but the evidence on the
severity
of the problem is far from conclusive. We need much more research into:
1) The methane reservoir in clathrates and permafrost
2) The size of potential methane sources currently frozen as
organic detritus
3) The likely changes to the GWP of methane in future
atmospheres, as the levels of hydroxyl radicals etc. shift over time
and as a direct result of methane excursion. Recent research on this
asks more questions than it answers.
My personal feeling is that the range of likely outcomes is
from
a significant amplification of AGW, right up to a 'Great Dying' sized
mass-extinction event when we come within a sneeze of sterilising the
entire planet. I'd be tempted to bet on the latter, but I wouldn't be
around to collect the winnings, so I'll keep my wallet in my pocket.
My suggestions is that geoengineers look at ways to clean up
the
methane from the atmosphere, and then lock down the resulting carbon.
My guess is we've got about 50 years to do this, but virtually no time
at all if the methane can't be dealt with once it's in the atmosphere.
Therefore, I'd support John out of precautionary principle-based
reasoning.
Nice
one, John; the train of argument is clear (of limpid clarity, in
fact!) The problem is that the people and institutions addressed are
in the business of politics, the art of the possible, rather than in
the business of logical evaluation. They hear what you are saying and
must see the validity of it. But politically what is true and what is
doable do not always coincide, as we all know from as many examples as
one cares to ennumerate.
We have to keep hammering away at the arguments, to the point at which
they are generally understood and accepted, and also keep on
politicking in the sure and certain hope that eventually the
acceptance of the arguments and the cowardice/caution/horse sense/
opportunistic careerism of the politicos will achieve the right kind
of intersection. In the next year or so (& wouldn't it be a great
help to have the environmental NGOs on board.)
On Nov 12, 10:51 pm, John Nissen <j...@cloudworld.co.uk>
wrote:
> It is incredible. It is so obvious.
>
> 1. Global warming is driven largely by atmospheric CO2 according
to the
> concentration above its pre-industrial level; and
>
> 2. After emissions are stopped it could take millenia for the
> concentration to fall back to that level, because the effective
lifetime
> of some of that excess CO2 is many thousands of years.
>
> Therefore:
> 3. Drastic emissions reduction, even to zero overnight, cannot
and will
> not stop the Arctic continuing to warm for decades.
>
> Therefore:
> 4. The Arctic sea ice will continue to retreat, accelerating the
warming
> due to the albedo effect.
>
> Therefore:
> 5. The permafrost will continue to thaw releasing increasing
quantities
> of methane, a potent greenhouse gas, potentially adding many
degrees to
> global warming; and
>
> 6. The Greenland ice sheet will become increasingly unstable,
> potentially contributing to an eventual sea level rise of 7 metres.
>
> Therefore:
> 7. To avoid these two catastrophes, we need to cool the Arctic
quickly
> enough to save the Arctic sea ice; and
>
> 8. Probably the only feasible way to do this is through solar
radiation
> management (SRM) geoengineering.
>
> 9. SRM is not a last resort, it is needed now to cool the Arctic.
>
> It is incredible that people do not seem to follow this train of
logic -
> it is so obvious.
>
> Yet when I challenged a panel of geoengineering experts to refute
this
> argument, the response was that geoengineering (even just to cool
the
> Arctic) was too dangerous - not that the argument was false! [1]
>
> So we continue to hear politicians and their advisers claiming that
> emissions reduction alone can be sufficient to keep the planet
safe. [2]
>
> And we continue to hear geoengineering experts saying that
> geoengineering should only be used as a last resort. [3]
>
> How can this mindset be changed quickly, to avoid leaving
geoengineering
> too late?
>
> John
>
> P.S. Apologies to those who have heard this all before and accept
the
> logic as self-evident.
>
> [1] This challenge was put to the panel at the launch of the Royal
> Society geoengineering report, on September 1st, with response
from the
> team leader and panel chairman, Professor John Shepherd.
>
> [2] For example at the geoengineering hearing at the House of
Commons,
> November 2008.
>
> [3] For example at the congressional hearing on geoengineering,
November
> 2009.
Thanks. I've never been accused of limpid clarity before!
But, seriously, there are people on this list, such as Alan Robock, who
would disagree with the argument. Alan?
Cheers,
John
--
jim woolridge wrote:
Nice one, John; the train of argument is clear (of limpid clarity, in
fact!) The problem is that the people and institutions addressed are
in the business of politics, the art of the possible, rather than in
the business of logical evaluation. They hear what you are saying and
must see the validity of it. But politically what is true and what is
doable do not always coincide, as we all know from as many examples as
one cares to ennumerate.
We have to keep hammering away at the arguments, to the point at which
they are generally understood and accepted, and also keep on
politicking in the sure and certain hope that eventually the
acceptance of the arguments and the cowardice/caution/horse sense/
opportunistic careerism of the politicos will achieve the right kind
of intersection. In the next year or so (& wouldn't it be a great
help to have the environmental NGOs on board.)
On Nov 12, 10:51 pm, John Nissen <j...@cloudworld.co.uk> wrote:
It is incredible. It is so obvious.
1. Global warming is driven largely by atmospheric CO2 according to the
concentration above its pre-industrial level; and
2. After emissions are stopped it could take millenia for the
concentration to fall back to that level, because the effective lifetime
of some of that excess CO2 is many thousands of years.
Therefore:
3. Drastic emissions reduction, even to zero overnight, cannot and will
not stop the Arctic continuing to warm for decades.
Therefore:
4. The Arctic sea ice will continue to retreat, accelerating the warming
due to the albedo effect.
Therefore:
5. The permafrost will continue to thaw releasing increasing quantities
of methane, a potent greenhouse gas, potentially adding many degrees to
global warming; and
6. The Greenland ice sheet will become increasingly unstable,
potentially contributing to an eventual sea level rise of 7 metres.
Therefore:
7. To avoid these two catastrophes, we need to cool the Arctic quickly
enough to save the Arctic sea ice; and
8. Probably the only feasible way to do this is through solar radiation
management (SRM) geoengineering.
9. SRM is not a last resort, it is needed now to cool the Arctic.
It is incredible that people do not seem to follow this train of logic -
it is so obvious.
Yet when I challenged a panel of geoengineering experts to refute this
argument, the response was that geoengineering (even just to cool the
Arctic) was too dangerous - not that the argument was false! [1]
So we continue to hear politicians and their advisers claiming that
emissions reduction alone can be sufficient to keep the planet safe. [2]
And we continue to hear geoengineering experts saying that
geoengineering should only be used as a last resort. [3]
How can this mindset be changed quickly, to avoid leaving geoengineering
too late?
John
P.S. Apologies to those who have heard this all before and accept the
logic as self-evident.
[1] This challenge was put to the panel at the launch of the Royal
Society geoengineering report, on September 1st, with response from the
team leader and panel chairman, Professor John Shepherd.
[2] For example at the geoengineering hearing at the House of Commons,
November 2008.
[3] For example at the congressional hearing on geoengineering, November
2009.
On point (4), lifetime of methane. This really worries me. Over time,
hydroxyl radicals (OH) will convert methane (CH4) into carbon dioxide
(CO2), which is less potent as a greenhouse gas. However, as a recent
study by Drew Shindell et al. concluded, CH4 will persist for far
longer in the atmosphere than the figures used in IPCC estimates.
The reason for this is scarcity of OH. Many atmospheric pollutants
compete for access to OH. In particular, carbon monoxide will elevate
concentrations of CH4 through scavenging of the OH that would
otherwise break down the CH4. What's most worrying is that an increase
of CH4 itself will severely exacerbate the problem. The Shindell study
estimates that increases in global CH4 emissions have already caused a
26% decrease in hydroxyl. Melting permafrost in the Arctic could cause
huge amounts of methane to be added that will also maintain their
highest levels of global warming potency for far longer than
previously thought.
On Mon, Nov 16, 2009 at 4:18 PM, John Nissen <j...@cloudworld.co.uk> wrote:
> Hi Andrew,
> You say: "I don't oppose John's argument, but the evidence on the severity
> of the problem is far from conclusive." I disagree.
> The methane presents a very real risk - because of the uncertainty on timing
> combined with the potential size of methane discharge - perhaps even enough
> to cause thermal runaway due to positive feedback, as is thought to have
> happened in the past [1]. Risk management involves identifying events and
> assessing them in terms of their likelihood and magnitude of impact [2].
> Thus something with a small likelihood (such as rapid massive methane
> excursion) can have a high risk, if the magnitude of impact is sufficiently
> large (and you can't get much larger than thermal runaway).
> It is possible that much or most of the methane trapped in frozen structures
> has built up over hundreds of thousands of years. There is little sign of
> massive methane discharge in the ice record. In fact methane seems to track
> the temperature even better than CO2 [3].
> But of course methane discharge is not the only high risk event - there is
> also the Greenland ice sheet disintegration.
> BTW, does anybody know the _immediate_ warming potential of methane, as
> opposed to the 20 year value (72), 100 years (25) or 500 years (7.6)? The
> lifetime is only 12 +/- 3 years. See [4].
> At present the likely methane excursion is far from clear. Further, it is
> also unclear how quickly the total excursion will occur. The excursion rate
> is highly significant due to the short life of methane in the atmosphere.
> The methane ends up as CO2, in itself a major issue. However, the CO2's
> likely effect is nothing compared to the devastating temperature spike which
> may result from a sudden methane excursion.
> I don't oppose John's argument, but the evidence on the severity of the
> problem is far from conclusive. We need much more research into:
> 1) The methane reservoir in clathrates and permafrost
> 2) The size of potential methane sources currently frozen as organic
> detritus
> 3) The likely changes to the GWP of methane in future atmospheres, as the
> levels of hydroxyl radicals etc. shift over time and as a direct result of
> methane excursion. Recent research on this asks more questions than it
> answers.
> My personal feeling is that the range of likely outcomes is from a
> significant amplification of AGW, right up to a 'Great Dying' sized
> mass-extinction event when we come within a sneeze of sterilising the entire
> planet. I'd be tempted to bet on the latter, but I wouldn't be around to
> collect the winnings, so I'll keep my wallet in my pocket.
> My suggestions is that geoengineers look at ways to clean up the methane
> from the atmosphere, and then lock down the resulting carbon. My guess is
> we've got about 50 years to do this, but virtually no time at all if the
> methane can't be dealt with once it's in the atmosphere. Therefore, I'd
> support John out of precautionary principle-based reasoning.
> A
> 2009/11/15 jim woolridge <jimwoolri...@hotmail.com>
>> Nice one, John; the train of argument is clear (of limpid clarity, in
>> fact!) The problem is that the people and institutions addressed are
>> in the business of politics, the art of the possible, rather than in
>> the business of logical evaluation. They hear what you are saying and
>> must see the validity of it. But politically what is true and what is
>> doable do not always coincide, as we all know from as many examples as
>> one cares to ennumerate.
>> We have to keep hammering away at the arguments, to the point at which
>> they are generally understood and accepted, and also keep on
>> politicking in the sure and certain hope that eventually the
>> acceptance of the arguments and the cowardice/caution/horse sense/
>> opportunistic careerism of the politicos will achieve the right kind
>> of intersection. In the next year or so (& wouldn't it be a great
>> help to have the environmental NGOs on board.)
>> On Nov 12, 10:51 pm, John Nissen <j...@cloudworld.co.uk> wrote:
>> > It is incredible. It is so obvious.
>> > 1. Global warming is driven largely by atmospheric CO2 according to the
>> > concentration above its pre-industrial level; and
>> > 2. After emissions are stopped it could take millenia for the
>> > concentration to fall back to that level, because the effective lifetime
>> > of some of that excess CO2 is many thousands of years.
>> > Therefore:
>> > 3. Drastic emissions reduction, even to zero overnight, cannot and will
>> > not stop the Arctic continuing to warm for decades.
>> > Therefore:
>> > 4. The Arctic sea ice will continue to retreat, accelerating the warming
>> > due to the albedo effect.
>> > Therefore:
>> > 5. The permafrost will continue to thaw releasing increasing quantities
>> > of methane, a potent greenhouse gas, potentially adding many degrees to
>> > global warming; and
>> > 6. The Greenland ice sheet will become increasingly unstable,
>> > potentially contributing to an eventual sea level rise of 7 metres.
>> > Therefore:
>> > 7. To avoid these two catastrophes, we need to cool the Arctic quickly
>> > enough to save the Arctic sea ice; and
>> > 8. Probably the only feasible way to do this is through solar radiation
>> > management (SRM) geoengineering.
>> > 9. SRM is not a last resort, it is needed now to cool the Arctic.
>> > It is incredible that people do not seem to follow this train of logic -
>> > it is so obvious.
>> > Yet when I challenged a panel of geoengineering experts to refute this
>> > argument, the response was that geoengineering (even just to cool the
>> > Arctic) was too dangerous - not that the argument was false! [1]
>> > So we continue to hear politicians and their advisers claiming that
>> > emissions reduction alone can be sufficient to keep the planet safe. [2]
>> > And we continue to hear geoengineering experts saying that
>> > geoengineering should only be used as a last resort. [3]
>> > How can this mindset be changed quickly, to avoid leaving geoengineering
>> > too late?
>> > John
>> > P.S. Apologies to those who have heard this all before and accept the
>> > logic as self-evident.
>> > [1] This challenge was put to the panel at the launch of the Royal
>> > Society geoengineering report, on September 1st, with response from the
>> > team leader and panel chairman, Professor John Shepherd.
>> > [2] For example at the geoengineering hearing at the House of Commons,
>> > November 2008.
>> > [3] For example at the congressional hearing on geoengineering, November
>> > 2009.
>> --
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John, Andrew
Re "BTW, does anybody know the _immediate_ warming potential of methane?"
Someone will correct me no doubt but my understanding is that warming is a rate process measured in W/m^2
So "instantaneous" [[== "immediate"?]] warming is an incorrect concept
Unless it continues for a second, a week, a year, 25 years, for whatever, no warming takes place.
So it is necessary to multiply by a duration to get joules/m^2
It's how many joules get into the low albedo meltwater on top of Greenland's ice that decides how much gets melted each year to fall down crevasses and lubricate the eventual collapse of large areas of ice into the oceans.
Meaning that the integral [[roughly]] under the CO2 level curve is what matters [multiplied by the warming potential over that period] when it comes to measuring threats of Greenland's collapse
So the key issue is duration - how long elevated greenhouse gas levels last and how to get them down. Think that's right Peter
----- Original Message ----- From: John Nissen To: andrew.lock...@gmail.com Cc: geoengineering Sent: Monday, November 16, 2009 6:18 PM
Subject: Re: [geo] Re: Rejected - a simple argument for SRM geoengineering
Hi Andrew,
You say: "I don't oppose John's argument, but the evidence on the severity of the problem is far from conclusive." I disagree.
The methane presents a very real risk - because of the uncertainty on timing combined with the potential size of methane discharge - perhaps even enough to cause thermal runaway due to positive feedback, as is thought to have happened in the past [1]. Risk management involves identifying events and assessing them in terms of their likelihood and magnitude of impact [2]. Thus something with a small likelihood (such as rapid massive methane excursion) can have a high risk, if the magnitude of impact is sufficiently large (and you can't get much larger than thermal runaway).
It is possible that much or most of the methane trapped in frozen structures has built up over hundreds of thousands of years. There is little sign of massive methane discharge in the ice record. In fact methane seems to track the temperature even better than CO2 [3].
But of course methane discharge is not the only high risk event - there is also the Greenland ice sheet disintegration.
BTW, does anybody know the _immediate_ warming potential of methane, as opposed to the 20 year value (72), 100 years (25) or 500 years (7.6)? The lifetime is only 12 +/- 3 years. See [4].
Andrew Lockley wrote: At present the likely methane excursion is far from clear. Further, it is also unclear how quickly the total excursion will occur. The excursion rate is highly significant due to the short life of methane in the atmosphere. The methane ends up as CO2, in itself a major issue. However, the CO2's likely effect is nothing compared to the devastating temperature spike which may result from a sudden methane excursion.
I don't oppose John's argument, but the evidence on the severity of the problem is far from conclusive. We need much more research into:
1) The methane reservoir in clathrates and permafrost
2) The size of potential methane sources currently frozen as organic detritus
3) The likely changes to the GWP of methane in future atmospheres, as the levels of hydroxyl radicals etc. shift over time and as a direct result of methane excursion. Recent research on this asks more questions than it answers.
My personal feeling is that the range of likely outcomes is from a significant amplification of AGW, right up to a 'Great Dying' sized mass-extinction event when we come within a sneeze of sterilising the entire planet. I'd be tempted to bet on the latter, but I wouldn't be around to collect the winnings, so I'll keep my wallet in my pocket.
My suggestions is that geoengineers look at ways to clean up the methane from the atmosphere, and then lock down the resulting carbon. My guess is we've got about 50 years to do this, but virtually no time at all if the methane can't be dealt with once it's in the atmosphere. Therefore, I'd support John out of precautionary principle-based reasoning.
A
2009/11/15 jim woolridge <jimwoolri...@hotmail.com>
Nice one, John; the train of argument is clear (of limpid clarity, in
fact!) The problem is that the people and institutions addressed are
in the business of politics, the art of the possible, rather than in
the business of logical evaluation. They hear what you are saying and
must see the validity of it. But politically what is true and what is
doable do not always coincide, as we all know from as many examples as
one cares to ennumerate.
We have to keep hammering away at the arguments, to the point at which
they are generally understood and accepted, and also keep on
politicking in the sure and certain hope that eventually the
acceptance of the arguments and the cowardice/caution/horse sense/
opportunistic careerism of the politicos will achieve the right kind
of intersection. In the next year or so (& wouldn't it be a great
help to have the environmental NGOs on board.)
On Nov 12, 10:51 pm, John Nissen <j...@cloudworld.co.uk> wrote:
> It is incredible. It is so obvious.
> 1. Global warming is driven largely by atmospheric CO2 according to the
> concentration above its pre-industrial level; and
> 2. After emissions are stopped it could take millenia for the
> concentration to fall back to that level, because the effective lifetime
> of some of that excess CO2 is many thousands of years.
> Therefore:
> 3. Drastic emissions reduction, even to zero overnight, cannot and will
> not stop the Arctic continuing to warm for decades.
> Therefore:
> 4. The Arctic sea ice will continue to retreat, accelerating the warming
> due to the albedo effect.
> Therefore:
> 5. The permafrost will continue to thaw releasing increasing quantities
> of methane, a potent greenhouse gas, potentially adding many degrees to
> global warming; and
> 6. The Greenland ice sheet will become increasingly unstable,
> potentially contributing to an eventual sea level rise of 7 metres.
> Therefore:
> 7. To avoid these two catastrophes, we need to cool the Arctic quickly
> enough to save the Arctic sea ice; and
> 8. Probably the only feasible way to do this is through solar radiation
> management (SRM) geoengineering.
> 9. SRM is not a last resort, it is needed now to cool the Arctic.
> It is incredible that people do not seem to follow this train of logic -
> it is so obvious.
> Yet when I challenged a panel of geoengineering experts to refute this
> argument, the response was that geoengineering (even just to cool the
> Arctic) was too dangerous - not that the argument was false! [1]
> So we continue to hear politicians and their advisers claiming that
> emissions reduction alone can be sufficient to keep the planet safe. [2]
> And we continue to hear geoengineering experts saying that
> geoengineering should only be used as a last resort. [3]
> How can this mindset be changed quickly, to avoid leaving geoengineering
> too late?
> John
> P.S. Apologies to those who have heard this all before and accept the
> logic as self-evident.
> [1] This challenge was put to the panel at the launch of the Royal
> Society geoengineering report, on September 1st, with response from the
> team leader and panel chairman, Professor John Shepherd.
> [2] For example at the geoengineering hearing at the House of Commons,
> November 2008.
> [3] For example at the congressional hearing on geoengineering, November
> 2009.
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Agreed, one has to consider a time period, so assume one takes a day that
when injected there is no decay over this period‹so it might as well be a
second of time one takes‹so virtually instantaneous. And I¹ll assume
linearity on methane absorption and logarithmic for CO2.
So, for methane, humans have caused an increase of roughly 1000 ppb which
converts to about 3 GtCH4, and this causes a forcing of about 0.5 W/m**2 (at
the tropopause) per IPCC.
For CO2, we know that a doubling (so we¹ll say from 300 to 600 ppm so we are
in the range of interest) causes a forcing of about 3.6 W/m**2 (at the
tropopause). So, 300 ppm of CO2 in the atmosphere is roughly 600 GtC or 2200
GtCO2 (and global warming potential is done for CO2, I believe.
So, if we take the ratio of forcing to mass for CH4 divided by the ratio of
forcing to mass for CO2, we get a rough estimate of the instantaneous GWP,
so
[0.5/3]/[3.6/2200] equals roughly 100
for the ratio at t=0 (so allowing for no decay) of the radiative forcing
caused by a unit mass of CH4 added to the atmosphere to a unit mass of CO2
added to the atmosphere.
Not exact, but plausible.
Mike
On 11/16/09 3:42 AM, "Peter Read" <pre...@attglobal.net> wrote:
> John, Andrew
> Re "BTW, does anybody know the _immediate_ warming potential of methane?"
> Someone will correct me no doubt but my understanding is that warming is a
> rate process measured in W/m^2
> So "instantaneous" [[== "immediate"?]] warming is an incorrect concept
> Unless it continues for a second, a week, a year, 25 years, for whatever, no
> warming takes place.
> So it is necessary to multiply by a duration to get joules/m^2
> It's how many joules get into the low albedo meltwater on top of Greenland's
> ice that decides how much gets melted each year to fall down crevasses and
> lubricate the eventual collapse of large areas of ice into the oceans.
> Meaning that the integral [[roughly]] under the CO2 level curve is what
> matters [multiplied by the warming potential over that period] when it comes
> to measuring threats of Greenland's collapse
> So the key issue is duration - how long elevated greenhouse gas levels last
> and how to get them down.
> Think that's right
> Peter
>> ----- Original Message -----
>> From: John Nissen <mailto:j...@cloudworld.co.uk>
>> Subject: Re: [geo] Re: Rejected - a simple argument for SRM geoengineering
>> Hi Andrew,
>> You say: "I don't oppose John's argument, but the evidence on the severity
>> of the problem is far from conclusive." I disagree.
>> The methane presents a very real risk - because of the uncertainty on timing
>> combined with the potential size of methane discharge - perhaps even enough
>> to cause thermal runaway due to positive feedback, as is thought to have
>> happened in the past [1]. Risk management involves identifying events and
>> assessing them in terms of their likelihood and magnitude of impact [2].
>> Thus something with a small likelihood (such as rapid massive methane
>> excursion) can have a high risk, if the magnitude of impact is sufficiently
>> large (and you can't get much larger than thermal runaway).
>> It is possible that much or most of the methane trapped in frozen structures
>> has built up over hundreds of thousands of years. There is little sign of
>> massive methane discharge in the ice record. In fact methane seems to track
>> the temperature even better than CO2 [3].
>> But of course methane discharge is not the only high risk event - there is
>> also the Greenland ice sheet disintegration.
>> BTW, does anybody know the _immediate_ warming potential of methane, as
>> opposed to the 20 year value (72), 100 years (25) or 500 years (7.6)? The
>> lifetime is only 12 +/- 3 years. See [4].
>> Andrew Lockley wrote:
>>> At present the likely methane excursion is far from clear. Further, it is
>>> also unclear how quickly the total excursion will occur. The excursion
>>> rate is highly significant due to the short life of methane in the
>>> atmosphere. The methane ends up as CO2, in itself a major issue. However,
>>> the CO2's likely effect is nothing compared to the devastating temperature
>>> spike which may result from a sudden methane excursion.
>>> I don't oppose John's argument, but the evidence on the severity of the
>>> problem is far from conclusive. We need much more research into:
>>> 1) The methane reservoir in clathrates and permafrost
>>> 2) The size of potential methane sources currently frozen as organic
>>> detritus
>>> 3) The likely changes to the GWP of methane in future atmospheres, as the
>>> levels of hydroxyl radicals etc. shift over time and as a direct result of
>>> methane excursion. Recent research on this asks more questions than it
>>> answers.
>>> My personal feeling is that the range of likely outcomes is from a
>>> significant amplification of AGW, right up to a 'Great Dying' sized
>>> mass-extinction event when we come within a sneeze of sterilising the entire
>>> planet. I'd be tempted to bet on the latter, but I wouldn't be around to
>>> collect the winnings, so I'll keep my wallet in my pocket.
>>> My suggestions is that geoengineers look at ways to clean up the methane
>>> from the atmosphere, and then lock down the resulting carbon. My guess is
>>> we've got about 50 years to do this, but virtually no time at all if the
>>> methane can't be dealt with once it's in the atmosphere. Therefore, I'd
>>> support John out of precautionary principle-based reasoning.
>>> A
>>> 2009/11/15 jim woolridge <jimwoolri...@hotmail.com>
>>>> Nice one, John; the train of argument is clear (of limpid clarity, in
>>>> fact!) The problem is that the people and institutions addressed are
>>>> in the business of politics, the art of the possible, rather than in
>>>> the business of logical evaluation. They hear what you are saying and
>>>> must see the validity of it. But politically what is true and what is
>>>> doable do not always coincide, as we all know from as many examples as
>>>> one cares to ennumerate.
>>>> We have to keep hammering away at the arguments, to the point at which
>>>> they are generally understood and accepted, and also keep on
>>>> politicking in the sure and certain hope that eventually the
>>>> acceptance of the arguments and the cowardice/caution/horse sense/
>>>> opportunistic careerism of the politicos will achieve the right kind
>>>> of intersection. In the next year or so (& wouldn't it be a great
>>>> help to have the environmental NGOs on board.)
>>>> On Nov 12, 10:51 pm, John Nissen <j...@cloudworld.co.uk> wrote:
>>>>> > It is incredible. It is so obvious.
>>>>> > 1. Global warming is driven largely by atmospheric CO2 according to the
>>>>> > concentration above its pre-industrial level; and
>>>>> > 2. After emissions are stopped it could take millenia for the
>>>>> > concentration to fall back to that level, because the effective
>>>>> lifetime
>>>>> > of some of that excess CO2 is many thousands of years.
>>>>> > Therefore:
>>>>> > 3. Drastic emissions reduction, even to zero overnight, cannot and
>>>>> will
>>>>> > not stop the Arctic continuing to warm for decades.
>>>>> > Therefore:
>>>>> > 4. The Arctic sea ice will continue to retreat, accelerating the
>>>>> warming
>>>>> > due to the albedo effect.
>>>>> > Therefore:
>>>>> > 5. The permafrost will continue to thaw releasing increasing
>>>>> quantities
>>>>> > of methane, a potent greenhouse gas, potentially adding many degrees to
>>>>> > global warming; and
>>>>> > 6. The Greenland ice sheet will become increasingly unstable,
>>>>> > potentially contributing to an eventual sea level rise of 7 metres.
>>>>> > Therefore:
>>>>> > 7. To avoid these two catastrophes, we need to cool the Arctic quickly
>>>>> > enough to save the Arctic sea ice; and
>>>>> > 8. Probably the only feasible way to do this is through solar
>>>>> radiation
>>>>> > management (SRM) geoengineering.
>>>>> > 9. SRM is not a last resort, it is needed now to cool the Arctic.
>>>>> > It is incredible that people do not seem to follow this train of logic
-
>>>>> > it is so obvious.
>>>>> > Yet when I challenged a panel of geoengineering experts to refute this
>>>>> > argument, the response was that geoengineering (even just to cool the
>>>>> > Arctic) was too dangerous - not that the argument was false! [1]
>>>>> > So we continue to hear politicians and their advisers claiming that
>>>>> > emissions reduction alone can be sufficient to keep the planet safe.
>>>>> [2]
>>>>> > And we continue to hear geoengineering experts saying that
>>>>> > geoengineering should only be used as a last resort. [3]
>>>>> > How can this mindset be changed quickly, to avoid leaving
>>>>> geoengineering
>>>>> > too late?
>>>>> > John
>>>>> > P.S. Apologies to those who have heard this all before and accept the
>>>>> > logic as self-evident.
>>>>> > [1] This challenge was put to the panel at the launch
The last line is the key and perfectly true. At last an honest broker. plausible. We are not dealing with solid science but rather with hypothesis and plausibility. Plausibility is not a lesser form of exactness. They are not related concepts. Nothing better than plausibility is available. So in an exact sense much of this discussion is hand waving. Very sorry but it is true. No one has predicted and then confirmed a result in hand so we have no theory and only an incomplete picture of the phenomena. We have to be careful and not get carried away.-gene
From: Mike MacCracken [mailto:mmacc...@comcast.net] Sent: Monday, November 16, 2009 9:52 AM
To: Peter Read; John Nissen; Andrew Lockley
Cc: Geoengineering
Subject: Re: [geo] Re: Rejected - a simple argument for SRM geoengineering
Agreed, one has to consider a time period, so assume one takes a day that when injected there is no decay over this period—so it might as well be a second of time one takes—so virtually instantaneous. And I’ll assume linearity on methane absorption and logarithmic for CO2.
So, for methane, humans have caused an increase of roughly 1000 ppb which converts to about 3 GtCH4, and this causes a forcing of about 0.5 W/m**2 (at the tropopause) per IPCC.
For CO2, we know that a doubling (so we’ll say from 300 to 600 ppm so we are in the range of interest) causes a forcing of about 3.6 W/m**2 (at the tropopause). So, 300 ppm of CO2 in the atmosphere is roughly 600 GtC or 2200 GtCO2 (and global warming potential is done for CO2, I believe.
So, if we take the ratio of forcing to mass for CH4 divided by the ratio of forcing to mass for CO2, we get a rough estimate of the instantaneous GWP, so
[0.5/3]/[3.6/2200] equals roughly 100
for the ratio at t=0 (so allowing for no decay) of the radiative forcing caused by a unit mass of CH4 added to the atmosphere to a unit mass of CO2 added to the atmosphere.
Not exact, but plausible.
Mike
On 11/16/09 3:42 AM, "Peter Read" <pre...@attglobal.net> wrote:
John, Andrew
Re "BTW, does anybody know the _immediate_ warming potential of methane?"
Someone will correct me no doubt but my understanding is that warming is a rate process measured in W/m^2
So "instantaneous" [[== "immediate"?]] warming is an incorrect concept
Unless it continues for a second, a week, a year, 25 years, for whatever, no warming takes place.
So it is necessary to multiply by a duration to get joules/m^2
It's how many joules get into the low albedo meltwater on top of Greenland's ice that decides how much gets melted each year to fall down crevasses and lubricate the eventual collapse of large areas of ice into the oceans.
Meaning that the integral [[roughly]] under the CO2 level curve is what matters [multiplied by the warming potential over that period] when it comes to measuring threats of Greenland's collapse
So the key issue is duration - how long elevated greenhouse gas levels last and how to get them down. Think that's right Peter
Subject: Re: [geo] Re: Rejected - a simple argument for SRM geoengineering
Hi Andrew,
You say: "I don't oppose John's argument, but the evidence on the severity of the problem is far from conclusive." I disagree.
The methane presents a very real risk - because of the uncertainty on timing combined with the potential size of methane discharge - perhaps even enough to cause thermal runaway due to positive feedback, as is thought to have happened in the past [1]. Risk management involves identifying events and assessing them in terms of their likelihood and magnitude of impact [2]. Thus something with a small likelihood (such as rapid massive methane excursion) can have a high risk, if the magnitude of impact is sufficiently large (and you can't get much larger than thermal runaway).
It is possible that much or most of the methane trapped in frozen structures has built up over hundreds of thousands of years. There is little sign of massive methane discharge in the ice record. In fact methane seems to track the temperature even better than CO2 [3].
But of course methane discharge is not the only high risk event - there is also the Greenland ice sheet disintegration.
BTW, does anybody know the _immediate_ warming potential of methane, as opposed to the 20 year value (72), 100 years (25) or 500 years (7.6)? The lifetime is only 12 +/- 3 years. See [4].
At present the likely methane excursion is far from clear. Further, it is also unclear how quickly the total excursion will occur. The excursion rate is highly significant due to the short life of methane in the atmosphere. The methane ends up as CO2, in itself a major issue. However, the CO2's likely effect is nothing compared to the devastating temperature spike which may result from a sudden methane excursion.
I don't oppose John's argument, but the evidence on the severity of the problem is far from conclusive. We need much more research into:
1) The methane reservoir in clathrates and permafrost
2) The size of potential methane sources currently frozen as organic detritus
3) The likely changes to the GWP of methane in future atmospheres, as the levels of hydroxyl radicals etc. shift over time and as a direct result of methane excursion. Recent research on this asks more questions than it answers.
My personal feeling is that the range of likely outcomes is from a significant amplification of AGW, right up to a 'Great Dying' sized mass-extinction event when we come within a sneeze of sterilising the entire planet. I'd be tempted to bet on the latter, but I wouldn't be around to collect the winnings, so I'll keep my wallet in my pocket.
My suggestions is that geoengineers look at ways to clean up the methane from the atmosphere, and then lock down the resulting carbon. My guess is we've got about 50 years to do this, but virtually no time at all if the methane can't be dealt with once it's in the atmosphere. Therefore, I'd support John out of precautionary principle-based reasoning.
A
2009/11/15 jim woolridge <jimwoolri...@hotmail.com>
Nice one, John; the train of argument is clear (of limpid clarity, in
fact!) The problem is that the people and institutions addressed are
in the business of politics, the art of the possible, rather than in
the business of logical evaluation. They hear what you are saying and
must see the validity of it. But politically what is true and what is
doable do not always coincide, as we all know from as many examples as
one cares to ennumerate.
We have to keep hammering away at the arguments, to the point at which
they are generally understood and accepted, and also keep on
politicking in the sure and certain hope that eventually the
acceptance of the arguments and the cowardice/caution/horse sense/
opportunistic careerism of the politicos will achieve the right kind
of intersection. In the next year or so (& wouldn't it be a great
help to have the environmental NGOs on board.)
On Nov 12, 10:51 pm, John Nissen <j...@cloudworld.co.uk> wrote:
> It is incredible. It is so obvious.
> 1. Global warming is driven largely by atmospheric CO2 according to the
> concentration above its pre-industrial level; and
> 2. After emissions are stopped it could take millenia for the
> concentration to fall back to that level, because the effective lifetime
> of some of that excess CO2 is many thousands of years.
> Therefore:
> 3. Drastic emissions reduction, even to zero overnight, cannot and will
> not stop the Arctic continuing to warm for decades.
> Therefore:
> 4. The Arctic sea ice will continue to retreat, accelerating the warming
> due to the albedo effect.
> Therefore:
> 5. The permafrost will continue to thaw releasing increasing quantities
> of methane, a potent greenhouse gas, potentially adding many degrees to
> global warming; and
> 6. The Greenland ice sheet will become increasingly unstable,
> potentially contributing to an eventual sea level rise of 7 metres.
> Therefore:
> 7. To avoid these two catastrophes, we need to cool the Arctic quickly
> enough to save the Arctic sea ice; and
> 8. Probably the only feasible way to do this is through solar radiation
> management (SRM) geoengineering.
> 9. SRM is not a last resort, it is needed now to cool the Arctic.
> It is incredible that people do not seem to follow this train of logic -
> it is so obvious.
> Yet when I challenged a panel of geoengineering experts to refute this
> argument, the response was that geoengineering (even just to cool the
> Arctic) was too dangerous - not that the argument was false! [1]
> So we continue to hear politicians and their advisers claiming that
> emissions reduction alone can be sufficient to keep the planet safe. [2]
> And we continue to hear geoengineering experts saying that
> geoengineering should only be used as a last resort. [3]
> How can this mindset be changed quickly, to avoid leaving geoengineering
> too late?
> John
> P.S. Apologies to those who have heard this all before and accept the
> logic as self-evident.
> [1] This challenge was put to the panel at the launch of the Royal
> Society geoengineering report, on September
As regards "immediate global warming potential (GWP)", Mike MacCracken
has just explained that, as you reduce the duration
from 20 years (when GWP is 72) down to near zero, the global warming
potential converges on a
value - which he estimates at around 100. That was the figure I was
looking for. Thanks, Mike.
However Peter, you are right that it is integration over time which
matters. This is
partly why Copenhagen is doomed to failure. Global warming is
proportional to climate forcing from excess greenhouse gases in
the atmosphere
(excess above pre-industrial levels), where this excess is an integration
of anthropogenic contributions over many decades. There is already an
enormous excess of CO2 in the atmosphere, sufficient for
global warming to continue for millennia. Emissions cuts just cannot
be
drastic enough to halt global warming in the required timescale.
I don't know how any scientist can deny this. Yet, in a desperate
attempt to
get government commitments at Copenhagen to cut CO2 emissions, it
appears that
scientists have conspired to lie to governments and the media,
by stating that emissions reductions by themselves can make the planet
safe for future generations. Having lied about this, they cannot then
turn round and say sorry but actually there need to be additional
actions:
(1) to actively remove CO2 from the atmosphere by
geoengineering techniques such as biochar;
(2) to cool the Arctic
by solar radiation management (SRM) geoengineering.
A consequence of the big lie is that scientists are now afraid to
admit that geoengineering is needed. And the SRM geoengineering is
needed particularly urgently, because they underestimated the speed of
sea ice
retreat in particular.
This is essentially cowardice, but there is also money at stake,
because
there is no financial motivation for scientists to come clean, and
accept both my simple argument for SRM geoengineering and your equally
simple argument for biochar, Peter. Climate scientists are only too
happy to continue
their research indefinitely, which somebody here described as
"fiddling while Rome burns" - quite an apt analogy.
How do we break out of this impasse? Can we hope that the media picks
up on the arguments, and the scientific consensus moves rapidly towards
a rational and comprehensive approach to saving the planet, taking the
politicians with them? Time is in short supply. A myopic focus on
emissions reduction, to exclusion of geoengineering, would be an
unmitigated disaster for humanity. Perhaps failure at Copenhagen will
provide an opportunity for a new, comprehensive approach, so
desperately needed.
Cheers from Chiswick,
John
---
Mike MacCracken wrote:
Agreed, one has to consider a time period, so
assume one takes a day that when injected there is no decay over this
period—so it might as well be a second of time one takes—so virtually
instantaneous. And I’ll assume linearity on methane absorption and
logarithmic for CO2.
So, for methane, humans have caused an increase of roughly 1000 ppb
which converts to about 3 GtCH4, and this causes a forcing of about 0.5
W/m**2 (at the tropopause) per IPCC.
For CO2, we know that a doubling (so we’ll say from 300 to 600 ppm so
we are in the range of interest) causes a forcing of about 3.6 W/m**2
(at the tropopause). So, 300 ppm of CO2 in the atmosphere is roughly
600 GtC or 2200 GtCO2 (and global warming potential is done for CO2, I
believe.
So, if we take the ratio of forcing to mass for CH4 divided by the
ratio of forcing to mass for CO2, we get a rough estimate of the
instantaneous GWP, so
[0.5/3]/[3.6/2200] equals roughly 100
for the ratio at t=0 (so allowing for no decay) of the radiative
forcing caused by a unit mass of CH4 added to the atmosphere to a unit
mass of CO2 added to the atmosphere.
John,
Andrew
Re "BTW, does anybody know the _immediate_
warming potential of methane?" Someone will correct me no doubt but my
understanding is that warming is a rate process measured in W/m^2
So "instantaneous" [[== "immediate"?]] warming is an incorrect concept
Unless it continues for a second, a week, a year, 25 years, for
whatever, no warming takes place.
So it is necessary to multiply by a duration to get joules/m^2
It's how many joules get into the low albedo meltwater on top of
Greenland's ice that decides how much gets melted each year to fall
down crevasses and lubricate the eventual collapse of large areas of
ice into the oceans.
Meaning that the integral [[roughly]] under the CO2 level curve is what
matters [multiplied by the warming potential over that period] when it
comes to measuring threats of Greenland's collapse
So the key issue is duration - how long elevated greenhouse gas levels
last and how to get them down.
Think that's right
Peter
Subject: Re: [geo] Re: Rejected - a simple argument for
SRM geoengineering
Hi Andrew,
You say: "I don't oppose John's argument, but the evidence on the
severity of the problem is far from conclusive." I disagree.
The methane presents a very real risk - because of the uncertainty on
timing combined with the potential size of methane discharge - perhaps
even enough to cause thermal runaway due to positive feedback, as is
thought to have happened in the past [1]. Risk management involves
identifying events and assessing them in terms of their likelihood and
magnitude of impact [2]. Thus something with a small likelihood (such
as rapid massive methane excursion) can have a high risk, if the
magnitude of impact is sufficiently large (and you can't get much
larger than thermal runaway).
It is possible that much or most of the methane trapped in frozen
structures has built up over hundreds of thousands of years. There is
little sign of massive methane discharge in the ice record. In fact
methane seems to track the temperature even better than CO2 [3].
But of course methane discharge is not the only high risk event -
there is also the Greenland ice sheet disintegration.
BTW, does anybody know the _immediate_ warming potential of methane,
as opposed to the 20 year value (72), 100 years (25) or 500 years
(7.6)? The lifetime is only 12 +/- 3 years. See [4].
At present the likely
methane excursion is far from clear. Further, it is also unclear how
quickly the total excursion will occur. The excursion rate is highly
significant due to the short life of methane in the atmosphere. The
methane ends up as CO2, in itself a major issue. However, the
In light of recent modeling results on the lifetime of CO2 in the atmosphere, I am concerned that the current time-integrated (not instantaneous) GWP estimate for CO2 has been underestimated and hence GWP's of other gases (esp short-lived gases) relative to CO2 have been overestimated. E.g., Eby et al., 2009:
http://ams.allenpress.com/perlserv/?request=get-abstract&doi=10.1175%... show that 20-30% of excess emissions of CO2 and 60-70% of the subsequent CO2-caused surface air temp anomally exists 10,000 years after emission. Isn't this (or is this?) a far larger total time-integrated GW effect than a mass equivalent emission of CH4? Experts please set me straight.
Thanks,
Greg
>Agreed, one has to consider a time period, so assume one takes a day >that when injected there is no decay over this period-so it might as >well be a second of time one takes-so virtually instantaneous. And >I'll assume linearity on methane absorption and logarithmic for CO2.
>So, for methane, humans have caused an increase of roughly 1000 ppb >which converts to about 3 GtCH4, and this causes a forcing of about >0.5 W/m**2 (at the tropopause) per IPCC.
>For CO2, we know that a doubling (so we'll say from 300 to 600 ppm >so we are in the range of interest) causes a forcing of about 3.6 >W/m**2 (at the tropopause). So, 300 ppm of CO2 in the atmosphere is >roughly 600 GtC or 2200 GtCO2 (and global warming potential is done >for CO2, I believe.
>So, if we take the ratio of forcing to mass for CH4 divided by the >ratio of forcing to mass for CO2, we get a rough estimate of the >instantaneous GWP, so
>[0.5/3]/[3.6/2200] equals roughly 100
>for the ratio at t=0 (so allowing for no decay) of the radiative >forcing caused by a unit mass of CH4 added to the atmosphere to a >unit mass of CO2 added to the atmosphere.
>John, Andrew
>Re "BTW, does anybody know the _immediate_ warming potential of methane?"
>Someone will correct me no doubt but my understanding is that >warming is a rate process measured in W/m^2
>So "instantaneous" [[== "immediate"?]] warming is an incorrect concept
>Unless it continues for a second, a week, a year, 25 years, for >whatever, no warming takes place.
>So it is necessary to multiply by a duration to get joules/m^2
>It's how many joules get into the low albedo meltwater on top of >Greenland's ice that decides how much gets melted each year to fall >down crevasses and lubricate the eventual collapse of large areas of >ice into the oceans.
>Meaning that the integral [[roughly]] under the CO2 level curve is >what matters [multiplied by the warming potential over that period] > when it comes to measuring threats of Greenland's collapse
>So the key issue is duration - how long elevated greenhouse gas >levels last and how to get them down.
>Think that's right
>Peter
>----- Original Message -----
>From: John Nissen <<mailto:j...@cloudworld.co.uk>mailto:j...@cloudworld.co.uk>
>Subject: Re: [geo] Re: Rejected - a simple argument for SRM geoengineering
>Hi Andrew,
>You say: "I don't oppose John's argument, but the evidence on the >severity of the problem is far from conclusive." I disagree.
>The methane presents a very real risk - because of the uncertainty >on timing combined with the potential size of methane discharge - >perhaps even enough to cause thermal runaway due to positive >feedback, as is thought to have happened in the past [1]. Risk >management involves identifying events and assessing them in terms >of their likelihood and magnitude of impact [2]. Thus something > with a small likelihood (such as rapid massive methane excursion) >can have a high risk, if the magnitude of impact is sufficiently >large (and you can't get much larger than thermal runaway).
>It is possible that much or most of the methane trapped in frozen >structures has built up over hundreds of thousands of years. There >is little sign of massive methane discharge in the ice record. In >fact methane seems to track the temperature even better than CO2 >[3].
>But of course methane discharge is not the only high risk event - >there is also the Greenland ice sheet disintegration.
>BTW, does anybody know the _immediate_ warming potential of methane, > as opposed to the 20 year value (72), 100 years (25) or 500 years >(7.6)? The lifetime is only 12 +/- 3 years. See [4].
>At present the likely methane excursion is far from clear. > Further, it is also unclear how quickly the total excursion will > occur. The excursion rate is highly significant due to the short >life of methane in the atmosphere. The methane ends up as CO2, in >itself a major issue. However, the CO2's likely effect is nothing >compared to the devastating temperature spike which may result from >a sudden methane excursion.
>I don't oppose John's argument, but the evidence on the severity of >the problem is far from conclusive. We need much more research >into:
>1) The methane reservoir in clathrates and permafrost
>2) The size of potential methane sources currently frozen as organic detritus
>3) The likely changes to the GWP of methane in future atmospheres, >as the levels of hydroxyl radicals etc. shift over time and as a >direct result of methane excursion. Recent research on this asks >more questions than it answers.
>My personal feeling is that the range of likely outcomes is from a > significant amplification of AGW, right up to a 'Great Dying' sized > mass-extinction event when we come within a sneeze of sterilising >the entire planet. I'd be tempted to bet on the latter, but I >wouldn't be around to collect the winnings, so I'll keep my wallet >in my pocket.
>My suggestions is that geoengineers look at ways to clean up the > methane from the atmosphere, and then lock down the resulting >carbon. My guess is we've got about 50 years to do this, but >virtually no time at all if the methane can't be dealt with once >it's in the atmosphere. Therefore, I'd support John out of >precautionary principle-based reasoning.
>A
>2009/11/15 jim woolridge <<>jimwoolri...@hotmail.com>
>Nice one, John; the train of argument is clear (of limpid clarity, in
>fact!) The problem is that the people and institutions addressed are
>in the business of politics, the art of the possible, rather than in
>the business of logical evaluation. They hear what you are saying and
>must see the validity of it. But politically what is true and what is
>doable do not always coincide, as we all know from as many examples as
>one cares to ennumerate.
>We have to keep hammering away at the arguments, to the point at which
>they are generally understood and accepted, and also keep on
>politicking in the sure and certain hope that eventually the
>acceptance of the arguments and the cowardice/caution/horse sense/
>opportunistic careerism of the politicos will achieve the right kind
>of intersection. In the next year or so (& wouldn't it be a great
>help to have the environmental NGOs on board.)
>On Nov 12, 10:51 pm, John Nissen <<>j...@cloudworld.co.uk> wrote:
>> It is incredible. It is so obvious.
>> 1. Global warming is driven largely by atmospheric CO2 according to the
>> concentration above its pre-industrial level; and
>> 2. After emissions are stopped it could take millenia for the
>> concentration to fall back to that level, because the effective lifetime
> > of some of that excess CO2 is many thousands of years.
>> Therefore:
>> 3. Drastic emissions reduction, even to zero overnight, cannot and will
>> not stop the Arctic continuing to warm for decades.
>> Therefore:
>> 4. The Arctic sea ice will continue to retreat, accelerating the warming
>> due to the albedo effect.
>> Therefore:
>> 5. The permafrost will continue to thaw releasing increasing quantities
>> of methane, a potent greenhouse gas, potentially adding many degrees to
>> global warming; and
>> 6. The Greenland ice sheet will become increasingly unstable,
>> potentially contributing to an eventual sea level rise of 7 metres.
>> Therefore:
>> 7. To avoid these two catastrophes, we need to cool the Arctic quickly
>> enough to save the Arctic sea ice; and
>> 8. Probably the only feasible way to do this is through solar radiation
>> management (SRM) geoengineering.
>> 9. SRM is not a last resort, it is needed now to cool the Arctic.
>> It is incredible that people do not seem to follow this train of logic -
>> it is so obvious.
>> Yet when I challenged a panel of geoengineering experts to refute this
>> argument, the response was that geoengineering (even just to cool the
>> Arctic) was too dangerous - not that the argument was false! [1]
First, I should have noted that the recent Shindell et al paper makes clear
that methane has roles in addition to its own GH effect, so my estimate does
not include that.
On the CO2 question, GWP is over a time period. Indeed, as the time is
stretched out, the GWPs for other species drop because the lifetime of the
CO2 perturbation is so long‹so CO2 certainly has to be controlled.
Over the 21st century only, however, the warming influence of emissions of
CO2 (ignoring the SO2 cooling influence with which it is associated) and of
the non-CO2 gases (plus black carbon) are about equal. I should note that
there is also the carryover effect of CO2 perturbation from emissions prior
to 2000, but if you want to slow near-term warming, the non-CO2 gases simply
have to be addressed (not doing so aggressively is why the temperature rise
curves for various stabilization scenarios do not start showing an effect
for a several decades). Sharply cutting black carbon, ozone precursor and
methane emissions, all of which need to be cut for other reasons‹and
developed nations have shown it is possible-- can have a quite rapid effect
in reducing radiative forcing (just as volcanic eruptions limiting solar
shows there can be a quite strong near-term effect‹on forcing and
temperature).
But certainly, we also have to reduce CO2 emissions.
Best, Mike
On 11/16/09 3:22 PM, "Greg Rau" <r...@llnl.gov> wrote:
> In light of recent modeling results on the lifetime of CO2 in the atmosphere,
> I am concerned that the current time-integrated (not instantaneous) GWP
> estimate for CO2 has been underestimated and hence GWP's of other gases (esp
> short-lived gases) relative to CO2 have been overestimated. E.g., Eby et al.,
> 2009:
> http://ams.allenpress.com/perlserv/?request=get-abstract&doi=10.1175%... > I2554.1
> show that 20-30% of excess emissions of CO2 and 60-70% of the subsequent
> CO2-caused surface air temp anomally exists 10,000 years after emission.
> Isn't this (or is this?) a far larger total time-integrated GW effect than a
> mass equivalent emission of CH4? Experts please set me straight.
> Thanks,
> Greg
>> Agreed, one has to consider a time period, so assume one takes a day that
>> when injected there is no decay over this period-so it might as well be a
>> second of time one takes-so virtually instantaneous. And I'll assume
>> linearity on methane absorption and logarithmic for CO2.
>> So, for methane, humans have caused an increase of roughly 1000 ppb which
>> converts to about 3 GtCH4, and this causes a forcing of about 0.5 W/m**2 (at
>> the tropopause) per IPCC.
>> For CO2, we know that a doubling (so we'll say from 300 to 600 ppm so we are
>> in the range of interest) causes a forcing of about 3.6 W/m**2 (at the
>> tropopause). So, 300 ppm of CO2 in the atmosphere is roughly 600 GtC or 2200
>> GtCO2 (and global warming potential is done for CO2, I believe.
>> So, if we take the ratio of forcing to mass for CH4 divided by the ratio of
>> forcing to mass for CO2, we get a rough estimate of the instantaneous GWP, so
>> [0.5/3]/[3.6/2200] equals roughly 100
>> for the ratio at t=0 (so allowing for no decay) of the radiative forcing
>> caused by a unit mass of CH4 added to the atmosphere to a unit mass of CO2
>> added to the atmosphere.
>> Not exact, but plausible.
>> Mike
>> On 11/16/09 3:42 AM, "Peter Read" <pre...@attglobal.net> wrote:
>>> John, Andrew
>>> Re "BTW, does anybody know the _immediate_ warming potential of methane?"
>>> Someone will correct me no doubt but my understanding is that warming is a
>>> rate process measured in W/m^2
>>> So "instantaneous" [[== "immediate"?]] warming is an incorrect concept
>>> Unless it continues for a second, a week, a year, 25 years, for whatever, no
>>> warming takes place.
>>> So it is necessary to multiply by a duration to get joules/m^2
>>> It's how many joules get into the low albedo meltwater on top of Greenland's
>>> ice that decides how much gets melted each year to fall down crevasses and
>>> lubricate the eventual collapse of large areas of ice into the oceans.
>>> Meaning that the integral [[roughly]] under the CO2 level curve is what
>>> matters [multiplied by the warming potential over that period] when it
>>> comes to measuring threats of Greenland's collapse
>>> So the key issue is duration - how long elevated greenhouse gas levels last
>>> and how to get them down.
>>> Think that's right
>>> Peter
>>>> ----- Original Message -----
>>>> From: John Nissen <mailto:j...@cloudworld.co.uk <mailto:j...@cloudworld.co.uk>
>>>> Subject: Re: [geo] Re: Rejected - a simple argument for SRM geoengineering
>>>> Hi Andrew,
>>>> You say: "I don't oppose John's argument, but the evidence on the severity
>>>> of the problem is far from conclusive." I disagree.
>>>> The methane presents a very real risk - because of the uncertainty on
>>>> timing combined with the potential size of methane discharge - perhaps
>>>> even enough to cause thermal runaway due to positive feedback, as is
>>>> thought to have happened in the past [1]. Risk management involves
>>>> identifying events and assessing them in terms of their likelihood and
>>>> magnitude of impact [2]. Thus something with a small likelihood (such as
>>>> rapid massive methane excursion) can have a high risk, if the magnitude of
>>>> impact is sufficiently large (and you can't get much larger than thermal
>>>> runaway).
>>>> It is possible that much or most of the methane trapped in frozen
>>>> structures has built up over hundreds of thousands of years. There is
>>>> little sign of massive methane discharge in the ice record. In fact
>>>> methane seems to track the temperature even better than CO2 [3].
>>>> But of course methane discharge is not the only high risk event - there is
>>>> also the Greenland ice sheet disintegration.
>>>> BTW, does anybody know the _immediate_ warming potential of methane, as
>>>> opposed to the 20 year value (72), 100 years (25) or 500 years (7.6)? The
>>>> lifetime is only 12 +/- 3 years. See [4].
>>>> Andrew Lockley wrote:
>>>>> At present the likely methane excursion is far from clear. Further, it
>>>>> is also unclear how quickly the total excursion will occur. The
>>>>> excursion rate is highly significant due to the short life of methane in
>>>>> the atmosphere. The methane ends up as CO2, in itself a major issue.
>>>>> However, the CO2's likely effect is nothing compared to the devastating
>>>>> temperature spike which may result from a sudden methane excursion.
>>>>> I don't oppose John's argument, but the evidence on the severity of the
>>>>> problem is far from conclusive. We need much more research into:
>>>>> 1) The methane reservoir in clathrates and permafrost
>>>>> 2) The size of potential methane sources currently frozen as organic
>>>>> detritus
>>>>> 3) The likely changes to the GWP of methane in future atmospheres, as the
>>>>> levels of hydroxyl radicals etc. shift over time and as a direct result
>>>>> of methane excursion. Recent research on this asks more questions than
>>>>> it answers.
>>>>> My personal feeling is that the range of likely outcomes is from a
>>>>> significant amplification of AGW, right up to a 'Great Dying' sized
>>>>> mass-extinction event when we come within a sneeze of sterilising the
>>>>> entire planet. I'd be tempted to bet on the latter, but I wouldn't be
>>>>> around to collect the winnings, so I'll keep my wallet in my pocket.
>>>>> My suggestions is that geoengineers look at ways to clean up the methane
>>>>> from the atmosphere, and then lock down the resulting carbon. My guess
>>>>> is we've got about 50 years to do this, but virtually no time at all if
>>>>> the methane can't be dealt with once it's in the atmosphere. Therefore,
>>>>> I'd support John out of precautionary principle-based reasoning.
>>>>> A
>>>>> 2009/11/15 jim woolridge <jimwoolri...@hotmail.com>
>>>>>> Nice one, John; the train of argument is clear (of limpid clarity, in
>>>>>> fact!) The problem is that the people and institutions addressed are
>>>>>> in the business of politics, the art of the possible, rather than in
>>>>>> the business of logical evaluation. They hear what you are saying and
>>>>>> must see the validity of it. But politically what is true and what is
>>>>>> doable do not always coincide, as we all know from as many examples as
>>>>>> one cares to ennumerate.
>>>>>> We have to keep hammering away at the arguments, to the point at which
>>>>>> they are generally understood and accepted, and also keep on
>>>>>> politicking in the sure and certain hope that eventually the
>>>>>> acceptance of the arguments and the
>First, I should have noted that the recent Shindell et al paper >makes clear that methane has roles in addition to its own GH effect, >so my estimate does not include that.
>On the CO2 question, GWP is over a time period. Indeed, as the time >is stretched out, the GWPs for other species drop because the >lifetime of the CO2 perturbation is so long-so CO2 certainly has to >be controlled.
My concern is that the standardly used 2007 IPCC GWP's did not take into account the new and longer CO2 lifetime and SAT anomalies recently shown by Eby et al. (2009), Solomon et al. (2009). etc, in addition to Caldeira and Hoffert's 1:100,000 combustion heat/GWP (what is this ratio of heat of formation/GWP for methane?). So if the goal is to limit not only the global warming Tmax but especially the time integral of this warming, we have (vastly?) underestimated the value of CO2 mitigation and overestimated the effects of other more potent but much shorter-lived gases when scaled to CO2 using the old IPCC values(?)
>Over the 21st century only, however, the warming influence of >emissions of CO2 (ignoring the SO2 cooling influence with which it >is associated) and of the non-CO2 gases (plus black carbon) are >about equal. I should note that there is also the carryover effect >of CO2 perturbation from emissions prior to 2000, but if you want to >slow near-term warming, the non-CO2 gases simply have to be >addressed (not doing so aggressively is why the temperature rise >curves for various stabilization scenarios do not start showing an >effect for a several decades). Sharply cutting black carbon, ozone >precursor and methane emissions, all of which need to be cut for >other reasons-and developed nations have shown it is possible-- can >have a quite rapid effect in reducing radiative forcing (just as >volcanic eruptions limiting solar shows there can be a quite strong >near-term effect-on forcing and temperature).
My concern is that we not only must limit the Tmax, but especially also the time integral of elevated T. Surely 1,000 yrs of +2degC would seem a lot more of a concern than 10 years of +4degC. Or if not I'd like to see climatologists do a impacts/costing function of such scenarios so that more accurate (relative) values of CO2, CH4, etc mitigation can be determined with regard to long term planet habitability. This has obvious and significant (R&D) policy implications.
>In light of recent modeling results on the lifetime of CO2 in the >atmosphere, I am concerned that the current time-integrated (not >instantaneous) GWP estimate for CO2 has been underestimated and >hence GWP's of other gases (esp short-lived gases) relative to CO2 >have been overestimated. E.g., Eby et al., 2009:
><http://*ams.allenpress.com/perlserv/?request=get-abstract&doi=10.1175%2F2 008JCLI2554.1>http://*ams.allenpress.com/perlserv/?request=get-abstract&doi =10.1175%2F2008JCLI2554.1
>show that 20-30% of excess emissions of CO2 and 60-70% of the >subsequent CO2-caused surface air temp anomally exists 10,000 years >after emission. Isn't this (or is this?) a far larger total >time-integrated GW effect than a mass equivalent emission of CH4? >Experts please set me straight.
>Thanks,
>Greg
>Agreed, one has to consider a time period, so assume one takes a day >that when injected there is no decay over this period-so it might as >well be a second of time one takes-so virtually instantaneous. And >I'll assume linearity on methane absorption and logarithmic for CO2.
>So, for methane, humans have caused an increase of roughly 1000 ppb >which converts to about 3 GtCH4, and this causes a forcing of about >0.5 W/m**2 (at the tropopause) per IPCC.
>For CO2, we know that a doubling (so we'll say from 300 to 600 ppm >so we are in the range of interest) causes a forcing of about 3.6 >W/m**2 (at the tropopause). So, 300 ppm of CO2 in the atmosphere is >roughly 600 GtC or 2200 GtCO2 (and global warming potential is done >for CO2, I believe.
>So, if we take the ratio of forcing to mass for CH4 divided by the >ratio of forcing to mass for CO2, we get a rough estimate of the >instantaneous GWP, so
>[0.5/3]/[3.6/2200] equals roughly 100
>for the ratio at t=0 (so allowing for no decay) of the radiative >forcing caused by a unit mass of CH4 added to the atmosphere to a >unit mass of CO2 added to the atmosphere.
>John, Andrew
>Re "BTW, does anybody know the _immediate_ warming potential of methane?"
>Someone will correct me no doubt but my understanding is that >warming is a rate process measured in W/m^2
>So "instantaneous" [[== "immediate"?]] warming is an incorrect concept
>Unless it continues for a second, a week, a year, 25 years, for >whatever, no warming takes place.
>So it is necessary to multiply by a duration to get joules/m^2
>It's how many joules get into the low albedo meltwater on top of >Greenland's ice that decides how much gets melted each year to fall >down crevasses and lubricate the eventual collapse of large areas of >ice into the oceans.
>Meaning that the integral [[roughly]] under the CO2 level curve is >what matters [multiplied by the warming potential over that period] > when it comes to measuring threats of Greenland's collapse
>So the key issue is duration - how long elevated greenhouse gas >levels last and how to get them down.
>Think that's right
>Peter
>----- Original Message -----
>From: John Nissen ><<mailto:j...@cloudworld.co.uk>mailto:j...@cloudworld.co.uk ><<mailto:j...@cloudworld.co.uk>mailto:j...@cloudworld.co.uk> >
>Subject: Re: [geo] Re: Rejected - a simple argument for SRM geoengineering
>Hi Andrew,
>You say: "I don't oppose John's argument, but the evidence on the >severity of the problem is far from conclusive." I disagree.
>The methane presents a very real risk - because of the uncertainty >on timing combined with the potential size of methane discharge - >perhaps even enough to cause thermal runaway due to positive >feedback, as is thought to have happened in the past [1]. Risk >management involves identifying events and assessing them in terms >of their likelihood and magnitude of impact [2]. Thus something > with a small likelihood (such as rapid massive methane excursion) >can have a high risk, if the magnitude of impact is sufficiently >large (and you can't get much larger than thermal runaway).
>It is possible that much or most of the methane trapped in frozen >structures has built up over hundreds of thousands of years. There >is little sign of massive methane discharge in the ice record. In >fact methane seems to track the temperature even better than CO2 >[3].
>But of course methane discharge is not the only high risk event - >there is also the Greenland ice sheet disintegration.
>BTW, does anybody know the _immediate_ warming potential of methane, > as opposed to the 20 year value (72), 100 years (25) or 500 years >(7.6)? The lifetime is only 12 +/- 3 years. See [4].
>At present the likely methane excursion is far from clear. > Further, it is also unclear how quickly the total excursion will > occur. The excursion rate is highly significant due to the short >life of methane in the atmosphere. The methane ends up as CO2, in >itself a major issue. However, the CO2's likely effect is nothing >compared to the devastating temperature spike which may result from >a sudden methane excursion.
>I don't oppose John's argument, but the evidence on the severity of >the problem is far from conclusive. We need much more research >into:
>1) The methane reservoir in clathrates and permafrost
>2) The size of potential methane sources currently frozen as organic detritus
>3) The likely changes to the GWP of methane in future atmospheres, >as the levels of hydroxyl radicals etc. shift over time and as a >direct result of methane excursion. Recent research on this asks >more questions than it answers.
>My personal feeling is that the range of likely outcomes is from a > significant amplification of AGW, right up to a 'Great Dying' sized
GWP's by design ignore all climate impacts beyond 100 years.
This has real consequences as it makes methane look relatively more
important that it should be, and it also overweight's the beneficial
impacts of biomass sequestration in some calculations.
While some traditional economists may assume that discounting allows
them to ignore any impact beyond 100 years, this GWP formula has long
been a point of contention as most of us do value the future of the
planet beyond 100 years.
Adopting a 100 year analysis horizon, as the IPCC generally does, takes
our eye off the long term consequences of dumping fossil carbon in the
atmosphere. The risk of sea level rise look much less serious if one
only looks a century out.
Scientific understanding about the long term impacts of fossil emissions
is decades old (see Jim Kasting's old papers for example), popular
realization of these facts is long overdue.
Cheers,
David
________________________________
From: Greg Rau [mailto:r...@llnl.gov] Sent: November 16, 2009 1:23 PM
To: mmacc...@comcast.net; geoengineering@googlegroups.com
Subject: Re: [geo] Re: Rejected - a simple argument for SRM
geoengineering
In light of recent modeling results on the lifetime of CO2 in the
atmosphere, I am concerned that the current time-integrated (not
instantaneous) GWP estimate for CO2 has been underestimated and hence
GWP's of other gases (esp short-lived gases) relative to CO2 have been
overestimated. E.g., Eby et al., 2009:
show that 20-30% of excess emissions of CO2 and 60-70% of the subsequent
CO2-caused surface air temp anomally exists 10,000 years after emission.
Isn't this (or is this?) a far larger total time-integrated GW effect
than a mass equivalent emission of CH4? Experts please set me straight.
Thanks,
Greg
Agreed, one has to consider a time period, so assume one takes a
day that when injected there is no decay over this period-so it might as
well be a second of time one takes-so virtually instantaneous. And I'll
assume linearity on methane absorption and logarithmic for CO2.
So, for methane, humans have caused an increase of roughly 1000
ppb which converts to about 3 GtCH4, and this causes a forcing of about
0.5 W/m**2 (at the tropopause) per IPCC.
For CO2, we know that a doubling (so we'll say from 300 to 600
ppm so we are in the range of interest) causes a forcing of about 3.6
W/m**2 (at the tropopause). So, 300 ppm of CO2 in the atmosphere is
roughly 600 GtC or 2200 GtCO2 (and global warming potential is done for
CO2, I believe.
So, if we take the ratio of forcing to mass for CH4 divided by
the ratio of forcing to mass for CO2, we get a rough estimate of the
instantaneous GWP, so
[0.5/3]/[3.6/2200] equals roughly 100
for the ratio at t=0 (so allowing for no decay) of the radiative
forcing caused by a unit mass of CH4 added to the atmosphere to a unit
mass of CO2 added to the atmosphere.
Not exact, but plausible.
Mike
On 11/16/09 3:42 AM, "Peter Read" <pre...@attglobal.net> wrote:
John, Andrew
Re "BTW, does anybody know the _immediate_ warming potential of
methane?"
Someone will correct me no doubt but my understanding is that
warming is a rate process measured in W/m^2
So "instantaneous" [[== "immediate"?]] warming is an incorrect
concept
Unless it continues for a second, a week, a year, 25 years, for
whatever, no warming takes place.
So it is necessary to multiply by a duration to get joules/m^2
It's how many joules get into the low albedo meltwater on top of
Greenland's ice that decides how much gets melted each year to fall down
crevasses and lubricate the eventual collapse of large areas of ice into
the oceans.
Meaning that the integral [[roughly]] under the CO2 level curve
is what matters [multiplied by the warming potential over that period]
when it comes to measuring threats of Greenland's collapse
So the key issue is duration - how long elevated greenhouse gas
levels last and how to get them down.
Think that's right
Peter
Subject: Re: [geo] Re: Rejected - a simple argument for
SRM geoengineering
Hi Andrew,
You say: "I don't oppose John's argument, but the
evidence on the severity of the problem is far from conclusive." I
disagree.
The methane presents a very real risk - because of the
uncertainty on timing combined with the potential size of methane
discharge - perhaps even enough to cause thermal runaway due to
positive feedback, as is thought to have happened in the past [1].
Risk management involves identifying events and assessing them in terms
of their likelihood and magnitude of impact [2]. Thus something with a
small likelihood (such as rapid massive methane excursion) can have a
high risk, if the magnitude of impact is sufficiently large (and you
can't get much larger than thermal runaway).
It is possible that much or most of the methane trapped
in frozen structures has built up over hundreds of thousands of years.
There is little sign of massive methane discharge in the ice record. In
fact methane seems to track the temperature even better than CO2 [3].
But of course methane discharge is not the only high
risk event - there is also the Greenland ice sheet disintegration.
BTW, does anybody know the _immediate_ warming potential
of methane, as opposed to the 20 year value (72), 100 years (25) or 500
years (7.6)? The lifetime is only 12 +/- 3 years. See [4].
At present the likely methane excursion is far from
clear. Further, it is also unclear how quickly the total excursion
will occur. The excursion rate is highly significant due to the short
life of methane in the atmosphere. The methane ends up as CO2, in
itself a major issue. However, the CO2's likely effect is nothing
compared to the devastating temperature spike which may result from a
sudden methane excursion.
I don't oppose John's argument, but the evidence on the
severity of the problem is far from conclusive. We need much more
research into:
1) The methane reservoir in clathrates and permafrost
2) The size of potential methane sources currently
frozen as organic detritus
3) The likely changes to the GWP of methane in future
atmospheres, as the levels of hydroxyl radicals etc. shift over time
and as a direct result of methane excursion. Recent research on this
asks more questions than it answers.
My personal feeling is that the range of likely outcomes
is from a significant amplification of AGW, right up to a 'Great Dying'
sized mass-extinction event when we come within a sneeze of sterilising
the entire planet. I'd be tempted to bet on the latter, but I wouldn't
be around to collect the winnings, so I'll keep my wallet in my pocket.
My suggestions is that geoengineers look at ways to
clean up the methane from the atmosphere, and then lock down the
resulting carbon. My guess is we've got about 50 years to do this, but
virtually no time at all if the methane can't be dealt with once it's
in the atmosphere. Therefore, I'd support John out of precautionary
principle-based reasoning.
A
2009/11/15 jim woolridge <jimwoolri...@hotmail.com>
Nice one, John; the train of argument is clear (of
limpid clarity, in
fact!) The problem is that the people and institutions
addressed are
in the business of politics, the art of the possible,
rather than in
the business of logical evaluation. They hear what you
are saying and
must see the validity of it. But politically what is
true and what is
doable do not always coincide, as we all know from as
many examples as
one cares to ennumerate.
We have to keep hammering away at the arguments, to the
point at which
they are generally understood and accepted, and also
keep on
politicking in the sure and certain hope that eventually
the
acceptance of the arguments and the
cowardice/caution/horse sense/
opportunistic careerism of the politicos will achieve
the right kind
of intersection. In the next year or so (& wouldn't it
be a great
help to have the environmental NGOs on board.)
On Nov 12, 10:51 pm, John Nissen <j...@cloudworld.co.uk>
wrote:
> It is incredible. It is so obvious.
> 1. Global warming is driven largely by atmospheric
CO2 according to the
> concentration above its pre-industrial level; and
> 2. After emissions are stopped it could take millenia
for the
> concentration to fall back to that level, because the
effective lifetime
> of some of that excess CO2 is many thousands
of years.
> Therefore:
> 3. Drastic emissions reduction, even to zero
overnight, cannot
Thanks, David. I agree. Failure to appreciate long term effects and ocean acidification impacts, together with questionable/opaque discounting schemes has I believe resulted in CO2 mitigation being greatly undervalued by the economists and this is significantly undermining policy and political will.
Regards,
Greg
>GWP's by design ignore all climate impacts beyond 100 years.
>This has real consequences as it makes methane look relatively more >important that it should be, and it also overweight's the beneficial >impacts of biomass sequestration in some calculations.
>While some traditional economists may assume that discounting allows >them to ignore any impact beyond 100 years, this GWP formula has >long been a point of contention as most of us do value the future of >the planet beyond 100 years.
>Adopting a 100 year analysis horizon, as the IPCC generally does, >takes our eye off the long term consequences of dumping fossil >carbon in the atmosphere. The risk of sea level rise look much less >serious if one only looks a century out.
>Scientific understanding about the long term impacts of fossil >emissions is decades old (see Jim Kasting's old papers for example), >popular realization of these facts is long overdue.
>Cheers,
>David
>From: Greg Rau [mailto:r...@llnl.gov]
>Sent: November 16, 2009 1:23 PM
>To: mmacc...@comcast.net; geoengineering@googlegroups.com
>Subject: Re: [geo] Re: Rejected - a simple argument for SRM geoengineering
>In light of recent modeling results on the lifetime of CO2 in the >atmosphere, I am concerned that the current time-integrated (not >instantaneous) GWP estimate for CO2 has been underestimated and >hence GWP's of other gases (esp short-lived gases) relative to CO2 >have been overestimated. E.g., Eby et al., 2009:
>http://*ams.allenpress.com/perlserv/?request=get-abstract&doi=10.1175%2F20 08JCLI2554.1
>show that 20-30% of excess emissions of CO2 and 60-70% of the >subsequent CO2-caused surface air temp anomally exists 10,000 years >after emission. Isn't this (or is this?) a far larger total >time-integrated GW effect than a mass equivalent emission of CH4? >Experts please set me straight.
>Thanks,
>Greg
>>Agreed, one has to consider a time period, so assume one takes a >>day that when injected there is no decay over this period-so it >>might as well be a second of time one takes-so virtually >>instantaneous. And I'll assume linearity on methane absorption and >>logarithmic for CO2.
>>So, for methane, humans have caused an increase of roughly 1000 ppb >>which converts to about 3 GtCH4, and this causes a forcing of about >>0.5 W/m**2 (at the tropopause) per IPCC.
>>For CO2, we know that a doubling (so we'll say from 300 to 600 ppm >>so we are in the range of interest) causes a forcing of about 3.6 >>W/m**2 (at the tropopause). So, 300 ppm of CO2 in the atmosphere is >>roughly 600 GtC or 2200 GtCO2 (and global warming potential is done >>for CO2, I believe.
>>So, if we take the ratio of forcing to mass for CH4 divided by the >>ratio of forcing to mass for CO2, we get a rough estimate of the >>instantaneous GWP, so
>>[0.5/3]/[3.6/2200] equals roughly 100
>>for the ratio at t=0 (so allowing for no decay) of the radiative >>forcing caused by a unit mass of CH4 added to the atmosphere to a >>unit mass of CO2 added to the atmosphere.
>>Not exact, but plausible.
>>Mike
>>On 11/16/09 3:42 AM, "Peter Read" <pre...@attglobal.net> wrote:
>>John, Andrew
>>Re "BTW, does anybody know the _immediate_ warming potential of methane?"
>>Someone will correct me no doubt but my understanding is that >>warming is a rate process measured in W/m^2
>>So "instantaneous" [[== "immediate"?]] warming is an incorrect concept
>>Unless it continues for a second, a week, a year, 25 years, for >>whatever, no warming takes place.
>>So it is necessary to multiply by a duration to get joules/m^2
>>It's how many joules get into the low albedo meltwater on top of >>Greenland's ice that decides how much gets melted each year to fall >>down crevasses and lubricate the eventual collapse of large areas >>of ice into the oceans.
>>Meaning that the integral [[roughly]] under the CO2 level curve is >>what matters [multiplied by the warming potential over that period] >> when it comes to measuring threats of Greenland's collapse
>>So the key issue is duration - how long elevated greenhouse gas >>levels last and how to get them down.
>>Think that's right
>>Peter
>>----- Original Message -----
>>From: John Nissen >><<mailto:j...@cloudworld.co.uk>mailto:j...@cloudworld.co.uk>
>>Subject: Re: [geo] Re: Rejected - a simple argument for SRM geoengineering
>>Hi Andrew,
>>You say: "I don't oppose John's argument, but the evidence on the >>severity of the problem is far from conclusive." I disagree.
>>The methane presents a very real risk - because of the uncertainty >>on timing combined with the potential size of methane discharge - >>perhaps even enough to cause thermal runaway due to positive >>feedback, as is thought to have happened in the past [1]. Risk >>management involves identifying events and assessing them in terms >>of their likelihood and magnitude of impact [2]. Thus something >> with a small likelihood (such as rapid massive methane excursion) >>can have a high risk, if the magnitude of impact is sufficiently >>large (and you can't get much larger than thermal runaway).
>>It is possible that much or most of the methane trapped in frozen >>structures has built up over hundreds of thousands of years. >> There is little sign of massive methane discharge in the ice >>record. In fact methane seems to track the temperature even better >> than CO2 [3].
>>But of course methane discharge is not the only high risk event - >>there is also the Greenland ice sheet disintegration.
>>BTW, does anybody know the _immediate_ warming potential of >>methane, as opposed to the 20 year value (72), 100 years (25) or >>500 years (7.6)? The lifetime is only 12 +/- 3 years. See [4].
>>Andrew Lockley wrote:
>>At present the likely methane excursion is far from clear. >> Further, it is also unclear how quickly the total excursion will >> occur. The excursion rate is highly significant due to the short >>life of methane in the atmosphere. The methane ends up as CO2, in >>itself a major issue. However, the CO2's likely effect is nothing >>compared to the devastating temperature spike which may result >>from a sudden methane excursion.
>>I don't oppose John's argument, but the evidence on the severity of >>the problem is far from conclusive. We need much more research >>into:
>>1) The methane reservoir in clathrates and permafrost
>>2) The size of potential methane sources currently frozen as >>organic detritus
>>3) The likely changes to the GWP of methane in future atmospheres, >>as the levels of hydroxyl radicals etc. shift over time and as a >>direct result of methane excursion. Recent research on this asks >>more questions than it answers.
>>My personal feeling is that the range of likely outcomes is from a >> significant amplification of AGW, right up to a 'Great Dying' >>sized mass-extinction event when we come within a sneeze of >>sterilising the entire planet. I'd be tempted to bet on the >>latter, but I wouldn't be around to collect the winnings, so I'll >>keep my wallet in my pocket.
>>My suggestions is that geoengineers look at ways to clean up the >> methane from the atmosphere, and then lock down the resulting >>carbon. My guess is we've got about 50 years to do this, but >>virtually no time at all if the methane can't be dealt with once >>it's in the atmosphere. Therefore, I'd support John out of >>precautionary principle-based reasoning.
>>A
>>2009/11/15 jim woolridge <jimwoolri...@hotmail.com>
>>Nice one, John; the train of argument is clear (of limpid clarity, in
>>fact!) The problem is that the people and institutions addressed are
>>in the business of politics, the art of the possible, rather than in
>>the business of logical evaluation. They hear what you are saying and
>>must see the validity of it. But politically what is true and what is
>>doable do not always coincide, as we all know from as many examples as
>>one cares to ennumerate.
>>We have to keep hammering away at the arguments, to the point at which
>>they are generally understood and accepted, and also keep on
>>politicking in the sure and certain hope that eventually the
>>acceptance of the arguments and the cowardice/caution/horse sense/
>>opportunistic careerism of the politicos will achieve the right kind
>>of intersection. In the next year or so (& wouldn't it be a great
>>help to have the environmental NGOs on board.)
The other problem with 100-year GWPs is that they tend to hide all that can
be done with the short-lived species (black carbon, methane, ozone
precursors), so what we really need to do is to use both 20 and 500+ year
GWPs. Use of 100-year GWPs covers up both of the important tails.
Mike
On 11/20/09 2:49 PM, "Greg Rau" <r...@llnl.gov> wrote:
> Thanks, David. I agree. Failure to appreciate long term effects and ocean
> acidification impacts, together with questionable/opaque discounting schemes
> has I believe resulted in CO2 mitigation being greatly undervalued by the
> economists and this is significantly undermining policy and political will.
> Regards,
> Greg
>> Greg
>> GWP's by design ignore all climate impacts beyond 100 years.
>> This has real consequences as it makes methane look relatively more important
>> that it should be, and it also overweight's the beneficial impacts of biomass
>> sequestration in some calculations.
>> While some traditional economists may assume that discounting allows them to
>> ignore any impact beyond 100 years, this GWP formula has long been a point of
>> contention as most of us do value the future of the planet beyond 100 years.
>> Adopting a 100 year analysis horizon, as the IPCC generally does, takes our
>> eye off the long term consequences of dumping fossil carbon in the
>> atmosphere. The risk of sea level rise look much less serious if one only
>> looks a century out.
>> Scientific understanding about the long term impacts of fossil emissions is
>> decades old (see Jim Kasting's old papers for example), popular realization
>> of these facts is long overdue.
>> Cheers,
>> David
>> From: Greg Rau [mailto:r...@llnl.gov]
>> Sent: November 16, 2009 1:23 PM
>> To: mmacc...@comcast.net; geoengineering@googlegroups.com
>> Subject: Re: [geo] Re: Rejected - a simple argument for SRM geoengineering
>> In light of recent modeling results on the lifetime of CO2 in the atmosphere,
>> I am concerned that the current time-integrated (not instantaneous) GWP
>> estimate for CO2 has been underestimated and hence GWP's of other gases (esp
>> short-lived gases) relative to CO2 have been overestimated. E.g., Eby et
>> al., 2009:
>> http://*ams.allenpress.com/perlserv/?request=get-abstract&doi=10.1175%2F200 8J
>> CLI2554.1
>> show that 20-30% of excess emissions of CO2 and 60-70% of the subsequent
>> CO2-caused surface air temp anomally exists 10,000 years after emission.
>> Isn't this (or is this?) a far larger total time-integrated GW effect than a
>> mass equivalent emission of CH4? Experts please set me straight.
>> Thanks,
>> Greg
>>> Agreed, one has to consider a time period, so assume one takes a day that
>>> when injected there is no decay over this period-so it might as well be a
>>> second of time one takes-so virtually instantaneous. And I'll assume
>>> linearity on methane absorption and logarithmic for CO2.
>>> So, for methane, humans have caused an increase of roughly 1000 ppb which
>>> converts to about 3 GtCH4, and this causes a forcing of about 0.5 W/m**2 (at
>>> the tropopause) per IPCC.
>>> For CO2, we know that a doubling (so we'll say from 300 to 600 ppm so we are
>>> in the range of interest) causes a forcing of about 3.6 W/m**2 (at the
>>> tropopause). So, 300 ppm of CO2 in the atmosphere is roughly 600 GtC or 2200
>>> GtCO2 (and global warming potential is done for CO2, I believe.
>>> So, if we take the ratio of forcing to mass for CH4 divided by the ratio of
>>> forcing to mass for CO2, we get a rough estimate of the instantaneous GWP,
>>> so
>>> [0.5/3]/[3.6/2200] equals roughly 100
>>> for the ratio at t=0 (so allowing for no decay) of the radiative forcing
>>> caused by a unit mass of CH4 added to the atmosphere to a unit mass of CO2
>>> added to the atmosphere.
>>> Not exact, but plausible.
>>> Mike
>>> On 11/16/09 3:42 AM, "Peter Read" <pre...@attglobal.net> wrote:
>>> John, Andrew
>>> Re "BTW, does anybody know the _immediate_ warming potential of methane?"
>>> Someone will correct me no doubt but my understanding is that warming is a
>>> rate process measured in W/m^2
>>> So "instantaneous" [[== "immediate"?]] warming is an incorrect concept
>>> Unless it continues for a second, a week, a year, 25 years, for whatever, no
>>> warming takes place.
>>> So it is necessary to multiply by a duration to get joules/m^2
>>> It's how many joules get into the low albedo meltwater on top of Greenland's
>>> ice that decides how much gets melted each year to fall down crevasses and
>>> lubricate the eventual collapse of large areas of ice into the oceans.
>>> Meaning that the integral [[roughly]] under the CO2 level curve is what
>>> matters [multiplied by the warming potential over that period] when it
>>> comes to measuring threats of Greenland's collapse
>>> So the key issue is duration - how long elevated greenhouse gas levels last
>>> and how to get them down.
>>> Think that's right
>>> Peter
>>> ----- Original Message -----
>>> From: John Nissen <mailto:j...@cloudworld.co.uk <mailto:j...@cloudworld.co.uk>
>>>> Subject: Re: [geo] Re: Rejected - a simple argument for SRM geoengineering
>>>> Hi Andrew,
>>>> You say: "I don't oppose John's argument, but the evidence on the severity
>>>> of the problem is far from conclusive." I disagree.
>>>> The methane presents a very real risk - because of the uncertainty on
>>>> timing combined with the potential size of methane discharge - perhaps
>>>> even enough to cause thermal runaway due to positive feedback, as is
>>>> thought to have happened in the past [1]. Risk management involves
>>>> identifying events and assessing them in terms of their likelihood and
>>>> magnitude of impact [2]. Thus something with a small likelihood (such as
>>>> rapid massive methane excursion) can have a high risk, if the magnitude of
>>>> impact is sufficiently large (and you can't get much larger than thermal
>>>> runaway).
>>>> It is possible that much or most of the methane trapped in frozen
>>>> structures has built up over hundreds of thousands of years. There is
>>>> little sign of massive methane discharge in the ice record. In fact
>>>> methane seems to track the temperature even better than CO2 [3].
>>>> But of course methane discharge is not the only high risk event - there is
>>>> also the Greenland ice sheet disintegration.
>>>> BTW, does anybody know the _immediate_ warming potential of methane, as
>>>> opposed to the 20 year value (72), 100 years (25) or 500 years (7.6)? The
>>>> lifetime is only 12 +/- 3 years. See [4].
>>>> Andrew Lockley wrote:
>>>> At present the likely methane excursion is far from clear. Further, it is
>>>> also unclear how quickly the total excursion will occur. The excursion
>>>> rate is highly significant due to the short life of methane in the
>>>> atmosphere. The methane ends up as CO2, in itself a major issue.
>>>> However, the CO2's likely effect is nothing compared to the devastating
>>>> temperature spike which may result from a sudden methane excursion.
>>>> I don't oppose John's argument, but the evidence on the severity of the
>>>> problem is far from conclusive. We need much more research into:
>>>> 1) The methane reservoir in clathrates and permafrost
>>>> 2) The size of potential methane sources currently frozen as organic
>>>> detritus
>>>> 3) The likely changes to the GWP of methane in future atmospheres, as the
>>>> levels of hydroxyl radicals etc. shift over time and as a direct result of
>>>> methane excursion. Recent research on this asks more questions than it
>>>> answers.
>>>> My personal feeling is that the range of likely outcomes is from a
>>>> significant amplification of AGW, right up to a 'Great Dying' sized
>>>> mass-extinction event when we come within a sneeze of sterilising the
>>>> entire planet. I'd be tempted to bet on the latter, but I wouldn't be
>>>> around to collect the winnings, so I'll keep my wallet in my pocket.
>>>> My suggestions is that geoengineers look at ways to clean up the methane
>>>> from the atmosphere, and then lock down the resulting carbon. My guess is
>>>> we've got about 50 years to do this, but virtually no time at all if the
>>>> methane can't be dealt with once it's in the atmosphere. Therefore, I'd
>>>> support John out of precautionary principle-based reasoning.
>>>> A
>>>> 2009/11/15 jim woolridge <jimwoolri...@hotmail.com>
>>>> Nice one, John; the train of argument is clear (of limpid clarity, in
>>>> fact!) The problem is that the people and institutions addressed are
>>>> in the business of politics, the art of the possible, rather than in
>>>> the business of logical
True, Jim Kasting's work on the long-term carbon cycle as impacted by human fossil fuel CO2 emissions is decades old. But brilliant though Jim is, he was not the first. See, e.g., the attached paper published in 1974 when it first dawned on me and others at NASA/GISS that we might be on to something important with the fossil fuel O2 greenhouse-climate issue. Who would have thought that Steve Schneider, Richard Sommerville, Jim Hansen and yours truly would be pounding the table in 2009 for the world to act to limit emissions? (Remember, the planetary climate was still cooling in the '70s.) My '74 Atmos Env. paper admittedly has (minor in the overall scheme of things) errors. Not too surprising for an early probes into the far horizons of humankind's future. (Still, Dave Keeling liked it.) Finding those conceptual errors might be fun exercise for a carbon cycle savvy reader 35 years later.
But mostly, I think, I was right about the longevity of the impacts of the fuel era of human history through persistent elevated CO2 levels. Nobody much listened at the time and the paper was buried in in the resting place of specialized academic journals, though I was able to resurrect it with the help of the Internet.
But Hey: Is anyone listening now? Will they care in Copenhagen?
Cheers,
Marty Hoffert
Professor Emeritus of Physics Andre and Bella Meyer Hall of Physics
4 Washington Place
New York University
New York, NY 10003-6621
>GWP's by design ignore all climate impacts beyond 100 years.
>This has real consequences as it makes methane look relatively more >important that it should be, and it also overweight's the beneficial >impacts of biomass sequestration in some calculations.
>While some traditional economists may assume that discounting allows >them to ignore any impact beyond 100 years, this GWP formula has >long been a point of contention as most of us do value the future of >the planet beyond 100 years.
>Adopting a 100 year analysis horizon, as the IPCC generally does, >takes our eye off the long term consequences of dumping fossil >carbon in the atmosphere. The risk of sea level rise look much less >serious if one only looks a century out.
>Scientific understanding about the long term impacts of fossil >emissions is decades old (see Jim Kasting's old papers for example), >popular realization of these facts is long overdue.
>Cheers,
>David
>From: Greg Rau [mailto:r...@llnl.gov]
>Sent: November 16, 2009 1:23 PM
>To: mmacc...@comcast.net; geoengineering@googlegroups.com
>Subject: Re: [geo] Re: Rejected - a simple argument for SRM geoengineering
>In light of recent modeling results on the lifetime of CO2 in the >atmosphere, I am concerned that the current time-integrated (not >instantaneous) GWP estimate for CO2 has been underestimated and >hence GWP's of other gases (esp short-lived gases) relative to CO2 >have been overestimated. E.g., Eby et al., 2009:
>http://ams.allenpress.com/perlserv/?request=get-abstract&doi=10.1175%... >show that 20-30% of excess emissions of CO2 and 60-70% of the >subsequent CO2-caused surface air temp anomally exists 10,000 years >after emission. Isn't this (or is this?) a far larger total >time-integrated GW effect than a mass equivalent emission of CH4? >Experts please set me straight.
>Thanks,
>Greg
>>Agreed, one has to consider a time period, so assume one takes a >>day that when injected there is no decay over this period-so it >>might as well be a second of time one takes-so virtually >>instantaneous. And I'll assume linearity on methane absorption and >>logarithmic for CO2.
>>So, for methane, humans have caused an increase of roughly 1000 ppb >>which converts to about 3 GtCH4, and this causes a forcing of about >>0.5 W/m**2 (at the tropopause) per IPCC.
>>For CO2, we know that a doubling (so we'll say from 300 to 600 ppm >>so we are in the range of interest) causes a forcing of about 3.6 >>W/m**2 (at the tropopause). So, 300 ppm of CO2 in the atmosphere is >>roughly 600 GtC or 2200 GtCO2 (and global warming potential is done >>for CO2, I believe.
>>So, if we take the ratio of forcing to mass for CH4 divided by the >>ratio of forcing to mass for CO2, we get a rough estimate of the >>instantaneous GWP, so
>>[0.5/3]/[3.6/2200] equals roughly 100
>>for the ratio at t=0 (so allowing for no decay) of the radiative >>forcing caused by a unit mass of CH4 added to the atmosphere to a >>unit mass of CO2 added to the atmosphere.
>>Not exact, but plausible.
>>Mike
>>On 11/16/09 3:42 AM, "Peter Read" <pre...@attglobal.net> wrote:
>>John, Andrew
>>Re "BTW, does anybody know the _immediate_ warming potential of methane?"
>>Someone will correct me no doubt but my understanding is that >>warming is a rate process measured in W/m^2
>>So "instantaneous" [[== "immediate"?]] warming is an incorrect concept
>>Unless it continues for a second, a week, a year, 25 years, for >>whatever, no warming takes place.
>>So it is necessary to multiply by a duration to get joules/m^2
>>It's how many joules get into the low albedo meltwater on top of >>Greenland's ice that decides how much gets melted each year to fall >>down crevasses and lubricate the eventual collapse of large areas >>of ice into the oceans.
>>Meaning that the integral [[roughly]] under the CO2 level curve is >>what matters [multiplied by the warming potential over that period] >> when it comes to measuring threats of Greenland's collapse
>>So the key issue is duration - how long elevated greenhouse gas >>levels last and how to get them down.
>>Think that's right
>>Peter
>>----- Original Message -----
>>From: John Nissen >><<mailto:j...@cloudworld.co.uk>mailto:j...@cloudworld.co.uk>
>>Subject: Re: [geo] Re: Rejected - a simple argument for SRM geoengineering
>>Hi Andrew,
>>You say: "I don't oppose John's argument, but the evidence on the >>severity of the problem is far from conclusive." I disagree.
>>The methane presents a very real risk - because of the uncertainty >>on timing combined with the potential size of methane discharge - >>perhaps even enough to cause thermal runaway due to positive >>feedback, as is thought to have happened in the past [1]. Risk >>management involves identifying events and assessing them in terms >>of their likelihood and magnitude of impact [2]. Thus something >> with a small likelihood (such as rapid massive methane excursion) >>can have a high risk, if the magnitude of impact is sufficiently >>large (and you can't get much larger than thermal runaway).
>>It is possible that much or most of the methane trapped in frozen >>structures has built up over hundreds of thousands of years. >> There is little sign of massive methane discharge in the ice >>record. In fact methane seems to track the temperature even better >> than CO2 [3].
>>But of course methane discharge is not the only high risk event - >>there is also the Greenland ice sheet disintegration.
>>BTW, does anybody know the _immediate_ warming potential of >>methane, as opposed to the 20 year value (72), 100 years (25) or >>500 years (7.6)? The lifetime is only 12 +/- 3 years. See [4].
>>Andrew Lockley wrote:
>>At present the likely methane excursion is far from clear. >> Further, it is also unclear how quickly the total excursion will >> occur. The excursion rate is highly significant due to the short >>life of methane in the atmosphere. The methane ends up as CO2, in >>itself a major issue. However, the CO2's likely effect is nothing >>compared to the devastating temperature spike which may result >>from a sudden methane excursion.
>>I don't oppose John's argument, but the evidence on the severity of >>the problem is far from conclusive. We need much more research >>into:
>>1) The methane reservoir in clathrates and permafrost
>>2) The size of potential methane sources currently frozen as >>organic detritus
>>3) The likely changes to the GWP of methane in future atmospheres, >>as the levels of hydroxyl radicals etc. shift over time and as a >>direct result of methane excursion. Recent research on this asks >>more questions than it answers.
>>My personal feeling is that the range of likely outcomes is from a >> significant amplification of AGW, right up to a 'Great Dying' >>sized mass-extinction event when we come within a sneeze of >>sterilising the entire planet. I'd be tempted to bet on the >>latter, but I wouldn't be around to collect the winnings, so
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