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John Latham
lat...@ucar.edu & john.l...@manchester.ac.uk
Tel. 303-444-2429 (H) & 303-497-8182 (W)
You say ...
"we can expect permafrost to release large quantities of methane, from
as early as 2011 onwards, which will lead inexorably to runaway
greenhouse warming and abrupt climate change."
This is guesswork, not science.
I do not want to sign this letter.
Tom.
+++++++++++++
CERN is a HQ of dedicated thought for knowledge with MANY academic participants due to teh huge data availabilitysame is required for global geo climate, from what i understand moresomy studies in astrophysics seem to pale into insignificance when it comes to down to earth problems (pun or no pun intended)the localised chaos theory associated with the life balance of this planet are immense////
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Please do not add my name to the letter. I think geoengineering is a false hope and highly prone to unintended consequences.
-- Ron
Dear Ron,
The letter argues that geoengineering is now our only hope - our only option to avoid sea ice disappearance and the possibility of catastrophic methane release - since only geoengineering can act quickly enough to cool the Arctic. Procrastination will reduce chances of success, as well as increase chances of unmanageable side effects.
Cheers,
John
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1. "Only a few scientists predicted this event for the coming decade,
and they were ridiculed". This sour grapes statement does not
strengthen a case for geoengineering. Then 'many more' scientists
now agree with the more severe assessment -- that implies the number
is still in the minority. Do you really expect action until you can
say that the vast majority of scientists now agree with the direction.
2. I think the tone of the request should be explicitly to urgently
*prepare* a SRM deployment capability, not for its ASAP deployment as
implied. Deployment would be a second gate. We will lose precious
time to develop a viable system if we try to pass the deployment gate
first. At the same time a governance framework needs to be
established and the holistic long-term consequences of any deployment
need to be far better quantified - how safe is it. This work should
be acknowledged as part of the process.
A comment to Jousif...
You say: "In science, there is no such thing as "only hope" or "only
option"". That's a fine motivational cliche but it is not hard coded
into science that N=>2, where N is the number of options. It is of
course entirely possible that SRM is the only thing we could do to
stop catastrophic climate change. That's not to say that this has yet
been adequately established within the scientific community.
Best regards,
Glyn
Here's my formulation of the original letter:
Let S = {x : x is a solution to a potential problem that is going to end
life as we know it}
Can you prove that the cardinality of S is 1?
I would argue that funding is necessary to establish a rigorous, widely
accepted definition of the problem. Spoken languages (the ones I know
at least) are not expressive enough.
Regards,
Yousif
I'm not sure what you mean by "establish a rigorous, widely accepted
definition of the problem." If I were to take a stab at that it would
be:
Climate change could, before the end of this century, through loss of
arable land and migration of insects and pathogens, cause 'permanent'
(>1,000 years) disruption of the global food production capability,
cause the fragile global economy to collapse, and greatly reduce the
human population that the planet is able to support. And a large,
rapid change to the climate may exceed the adaptive capability of
ecosystems and biomes, and therefore trigger massive extinctions.
Mitigation alone may not be sufficient to prevent this outcome, and
CDR may prove not to be viable.
As you expertly expressed "Developing SRM capabilities should be
considered very seriously."
Glyn
However in a 2007 review of scientific papers [1] it concluded that
permafrost methane was not a top priority tipping point issue "Recent
permafrost melt in Siberia has been described in the popular media as
a tipping point because it is accompanied by increased fluxes of
methane and carbon dioxide that contribute to the greenhouse effect.
However, existing future projections of permafrost melt, although
substantial, are quasi-linear and do not exhibit threshold behaviour
[ref provided in paper]. These projections ignore the positive
feedback from methane emissions, but it is estimated to be weak [ref
provided in paper] at the global scale and hence cannot promote a
strongly non-linear regional response. The inclusion of an estimated
∼400 PgC of methane stored in frozen hydrate reservoirs under the
boreal permafrost could strengthen the feedback somewhat. However, no
studies to date convincingly demonstrate that it is a tipping element
by our definition. "
Has their work been discredited in your opinion?
[1] "Tipping elements in the Earth's climate system", Lenton, et al
(see supporting information (SI) Appendix 1)
http://www.pnas.org/content/105/6/1786.long
Glyn
Did Glyn miss Boucher and Folberth, Atmospheric Environment 44 (2010)
3343–3345 which Ken circulated earlier this week?
Is the track record of prediction accuracy of climate scientists high
enough for us to bet the planet on them always being correct? The best
ones that I know are not that arrogant.
Stephen
Emeritus Professor of Engineering Design
School of Engineering and Electronics
University of Edinburgh
Mayfield Road
Edinburgh EH9 3JL
Scotland
tel +44 131 650 5704
fax +44 131 650 5702
Mobile 07795 203 195
S.Sa...@ed.ac.uk
http://www.see.ed.ac.uk/~shs
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The University of Edinburgh is a charitable body, registered in
Scotland, with registration number SC005336.
I don't understand your use of the word arrogant. The danger of
climate change may exceed the scenario projections (not "predictions")
from the climate scientists. Likewise, the danger of geoengineering
may exceed the opinion of a few of those in this group. Either side
may claim arrogance. But I don't feel arrogance is the big factor --
intelligent, learned people will differ on the relative risks.
I side in favour of aggressively developing an SRM capability while
simultaneously advancing a viable governance framework and advancing
research to better quantify the environmental impact of deployment
(compared to a no-deployment baseline). I hope we could be ready with
those critical elements in a few years. That seems to me as the best
case scenario regardless of whether we have that much time to avoid
triggering tipping points.
Time for a reality check.
It has been the slowest July Arctic melt in the eight year JAXA record.
Ice extent has declined at less than half the rate of 2007, and total ice loss has been more than 200,000 km² less than the previous low in 2004.
DMI now shows Arctic ice extent as second highest for the date, topped only by 2005.
Closeup below.
Cryosphere Today shows that ice extent and concentration is about the same as it was 20 years ago.
The modified NSIDC map below shows in green, areas where ice is present in 2010 but was not present in 2007.
The modified NSIDC map below shows (in red) ice loss over the last week. Note that ice extent has increased slightly in the Chukchi and Beaufort Seas, while it has declined slightly in the East Siberian Sea.
The modified NSIDC map below shows the record low ice loss since the first of the month.
The modified NSIDC map below shows ice loss since early April.
The graph below shows PIPS ice thickness over the last five years. Average ice thickness in 2010 continues to track a little below 2006. It should bottom out in the next week or so between 2006 and 2009.
The low ice loss is consistent with the low Arctic temperatures we have seen this summer.
The North Pole webcam below shows that the meltponds are frozen over. Temperatures have been below -5°C this week. Very cold for July.
David Schnare
But much of that ice was thin and new. The warmest April on record in the Arctic made short work of it." ... [Dr. Serreze's] data could be underestimating the collapse of summer ice cover, said David Barber of the University of Manitoba. Researchers can't learn anything from satellite data about the state or thickness of the ice."