Lindzen on climate sensitivity
Coby Beck
Sceptic" guide on the argument that the current warming in light of 35%
CO2 increase shows that climate sensitivity in the models is way too
high.
The article is here:
http://illconsidered.blogspot.com/2006/06/observations-show-climate-sensitivity.html
and I believe the argument originates with Lindzen. I have a challenge
in the comments that I am not able to address properly, specifically:
- is Lindzen correct that 35% CO2 applies a forcing that is 75% of 2x
CO2?
The very recent presentation of Lindzen's is here:
http://www.timbro.se/pdf/060505_r_lindzen.pdf
Constructive comments on the quality and content of this article in
general are much apreciated.
Coby
Eric Swanson
Coby Beck wrote:
> The very recent presentation of Lindzen's is here:
> http://www.timbro.se/pdf/060505_r_lindzen.pdf
>
> Constructive comments on the quality and content of this article in
> general are much apreciated.
Tim Lambert pointed to this presentation a while back.
I looked at it and wondered about the graph of historical temperature
shown on page 29. My first thought was that the smoothed curve should
not have extended to the last year in the upper panel. Then I went to
the CRU and downloaded their historical data, plotted it along with a 9
year sliding window. The results did not come close to that which
Lindzen presented.
http://www.cru.uea.ac.uk/cru/climon/data/themi/n17.htm
I e-mailed him and asked for a link to his data. He first replied that
he couldn't find it. Then, after another query, he suggested he might
have used "Hansen's data" or a graph from TIME. Well, it turns out
that the data from GISS looks quite like that from the CRU. I've
since checked the Hadley site and their data (which is also derived
from the CRU) doesn't look like that which Lindzen presented.
http://hadobs.metoffice.com/hadcrut3/diagnostics/hemispheric/northern/annual
It's rather difficult to see how Lindzen might have produced this graph
from the referenced data. It's also really hard to understand his
comment on the same page:
"The records on the right are completely consistent with a rapid
rise from 1976 to 1986 and almost no rise since."
Is Lindzen twisting the facts a bit? Inquiring minds want to know.
Roger Coppock
"several decades" in your closing with "about
half-a-century."
steve
If Lindzen cannot give a definitive answer to where he got his data
from then he deserves the criticism he gets. However, this criticism
cuts both ways and remains the primary reason I am a human-induced
global warming skeptic. GW proponents have done their fair share of
data and source code obfuscation.
The goal here is to get to the truth. In my university, I was taught
that a theory is valid only if can legitimately explain away any
contradiction. Since GW proponents have assumed a majority, there has
risen an aire of summary dismissal of skeptics, as if the debate were
over. When one bothers to look at the extent of questions raised by
skeptics that remain unaddressed, I see that the debate is FAR from
over.
Even though I remain a skeptic, I do everything I can to minimize my
carbon footprint. I love this planet. As long as GW proponents avoid
full transparency, I consider them AWOL in their responsibility to
answer every critic, be they legitimate or lunatic.
James Annan
> - is Lindzen correct that 35% CO2 applies a forcing that is 75% of 2x
> CO2?
No.
The CO2 rise alone will account for ln(1.35)/ln(2) = 43% of the effect
of a doubling. Crowley gives the total GHG effect at about 2.4W/m^2,
which would only be 75% of the doubling if a doubling was 3.2W/m^2. In
fact it is about 3.7W/m^2, so a 35% increase in CO2 gives 54% of a
doubling. So 75% is an overestimate of all GHGs, and note furthermore
that this also ignores the cooling effect of aerosols (about 1W, making
a total anthropogenic forcing of 1.4W or about 40% of a CO2 doubling).
There also happen to have been a few unusually large volcanoes in the
last couple of decades, without which a slightly greater warming would
probably have been seen.
Crowley's slighly out of data data are here:
<ftp://ftp.ncdc.noaa.gov/pub/data/paleo/gcmoutput/crowley2000/forc-total-4_12_01.txt>
>
> The very recent presentation of Lindzen's is here:
> http://www.timbro.se/pdf/060505_r_lindzen.pdf
>
> Constructive comments on the quality and content of this article in
> general are much apreciated.
His point about the (relative) lack of warming is at best disingenous:
since I can't believe that a scientist of his experience does not
understand the concept of heat capacity, it is hard to avoid the
conclusion that he's being deliberately dishonest. And this seems to be
his sole talking point now that he has no plausible meteorological
theory left to discuss.
FWIW I can't see many of the embedded graphics in the pdf (using on a
mac). Somehow, I doubt I'm missing much.
James
Roger Coppock
> theory is valid only if can legitimately
> explain away any contradiction.
Then you were taught incorrect statements at your
university. Quantum Mechanics, for just one example
out of many possible cases, is full of unexplained
contradictions. Yet, it makes valid predictions.
Coby Beck
I believe I have read Gavin on RealClimate using 20 to 30 years. I
suppose given the shape of the curve it is a bit of a judgment call.
Coby
steve
Roger Coppock wrote:
I'll buy your QM example. Historical precedent can satisfy me in the
face of mathematical inconsistencies. Human-Induced Global Warming
(HIGW) theory and climate modeling, though, have neither a lengthy
record of predictive success nor an uncontested mathematical basis (in
my opinion).
HIGW proponents are asking us to believe that man represents a
paradigm shift in the way we must think about global climate. And
because man is such an dominant phenomenon on the planet, and in the
face of events such as glacial melting and ultra-violent storms (things
not seen in recorded history), that becomes a plausible belief.
Skeptics, however, have shown that what is happening now (at least
temperature- and CO2-wise) has happened many times in the past.
Nothing, so far, is new. It is, therefore, incumbent on HIGW proponents
to dispel each skeptical argument.
Because I am tempted to believe that man is having at least some
impact, my threshold of convincability is relatively low. What I would
like to see is Professor Mann's tree ring analysis applied to a 1000
year data set that includes as much of the 1900's as possible. The
debate over the "hockey stick" has deteriorated into a mathematical
pissing contest of subtle proportions. If the HIGW community would join
with skeptics to promote funding an effort to "top off" the data set by
coring trees for that data, a pittance compared to implementing Kyoto,
the world would see a more truthful representation of the planet's
temperature history for the past 1000 years. Is that too much to ask?
Michael Tobis
I find this gratuitously insulting, and think it's quite marginal
whether we should have moderated it up.
I'll leave this calumny for later, but the answer is similar to my
answer to this one:
> I consider them AWOL in their responsibility
> to answer every critic, be they legitimate or lunatic.
Lewis Carroll answered that one:
==>
The sea was wet as wet could be,
The sands were dry as dry.
You could not see a cloud, because
No cloud was in the sky:
No birds were flying overhead--
There were no birds to fly.
The Walrus and the Carpenter
Were walking close at hand;
They wept like anything to see
Such quantities of sand:
"If this were only cleared away,"
They said, "it would be grand!"
"If seven maids with seven mops
Swept it for half a year.
Do you suppose," the Walrus said,
"That they could get it clear?"
"I doubt it," said the Carpenter,
And shed a bitter tear.
<===
Seriously, who or "GW proponents", and what obligates them (us?) to
"answer every critic, be they legitimate or lunatic"? And how is this
massive work to be funded/supported?
Clearly, the best answers come from those most qualified, and therefore
those who have dedicated themselves to science, and not to
communication.
Some of us are doing our level best to improve the quality of the
conversation, but this is (for instance in the case of the present
mailing list) often by way of genuine pro-bono work. It doesn't even
"look good" on our resumes; scientific establishments prefer to hire
scientists without strong opinions. In my own case, if I apply for work
at a university or a national lab as a scientific programmer or
computer science faculty, my efforts in getting this group going
emphatically will not appear on my resume.
There are plenty of mechanisms for relatively unqualified people to
express their opinions, oftentimes a priori set by their employers.
They are happy to round up supporters by spinning their position into
part of a package of popularly held political opinions, thus rounding
up plenty of troops to echo their messages. The amount of sand that
these people can throw vastly exceeds the amount of sand that
well-informed people can shovel.
This can cut either way. There is junk science everywhere there is
money at stake. The problem is that in a battle of science versus
politics, science wins the scientific battles and politics wins the
political battles.
If you pay me to spend all my time answering the nonsense spewed in
this sphere, I assure you that I will be happy to abandon my other
pursuits and do so. At the moment, I am answering you rather than
writing code or preparing to teach my class, activities for which I am
paid.
I can easily find a practically unbounded set of more flatly incorrect
messages that nobody has answered, but unfortunately nobody is paying
me to answer them.
mt
Raymond Arritt
> If the HIGW community would join
> with skeptics to promote funding an effort to "top off" the data set by
> coring trees for that data, a pittance compared to implementing Kyoto,
> the world would see a more truthful representation of the planet's
> temperature history for the past 1000 years. Is that too much to ask?
You seem to take the view that there are two opposing camps ("HGW
proponents" and "skeptics") that are fighting it out. That's a common
view based on the prevailing practice in settling legal disputes or
political problems.
But it's not science.
Yes, there are true believers and professional skeptics within the
scientific community. But with all respect to those individuals (some
of whom are personal friends) such attitudes are scientifically
indefensible. You must go with wherever the evidence takes you despite
any preconvieved notions.
Today anthropogenic global warming is the most consistent explanation
for a wide variety of experimental and theoretical findings -- surface
observations, satellite observations, numerical model results, proxy
records, and so on. Tomorrow the situation may be different, depending
on what new evidence appears in the next 24 hours. It can be maddening
to the public and politicians that scientists don't "stick to their
guns" consistently, but that's how science works.
Getting back to your original subject, your tree coring experiment
would be somewhat interesting but it wouldn't prove or disprove the
principles of radiative transfer or atmosphere-ocean dynamics on which
projections of global warming are based.
Coby Beck
> The goal here is to get to the truth. In my university, I was taught
> that a theory is valid only if can legitimately explain away any
> contradiction.
Contradictions can invalidate a theory, but as you have stated it this
is much too stongly worded. Perhaps a better goal is to provide the
simplest possible explanation for all available evidence.
> Since GW proponents have assumed a majority, there has
> risen an aire of summary dismissal of skeptics, as if the debate were
> over.
With respect, this could well be a result of the conclusivity of the
evidence rather than "majority rule" or political pressure to conform.
Widespread consensus among experts, improving agreement of model
results and increasingly similar physical representations of the
climate system from model to model is also perfectly consistent with
better and better understanding. This is coming fast as we gather more
and more historical and current data, all of which provides more
testing grounds for model refinement.
Seeing collusion instead of consensus is quite a dramatic take on what
is really just the normal course of scientific investigation. I suppose
fewer and fewer scientists disagreeing is consistent with more and more
supression of ideas, but you know, it is also the result of having the
right answer.
> When one bothers to look at the extent of questions raised by
> skeptics that remain unaddressed, I see that the debate is FAR from
> over.
Would you be kind enough to enumerate these questions? I have taken it
apon myself to attempt a catalogue of all *answered* sceptical question
in this issue, I would like to know if I have missed any. I also
invite you see if I might have an answer already:
http://illconsidered.blogspot.com/2006/02/how-to-talk-to-global-warming-sceptic.html
(caveat: please, nothing about the Hockey Stick. This is a single
study whose political stature far exceeds its current scientific
importance in the broader issue of current and future warming)
> Even though I remain a skeptic, I do everything I can to minimize my
> carbon footprint. I love this planet. As long as GW proponents avoid
> full transparency, I consider them AWOL in their responsibility to
> answer every critic, be they legitimate or lunatic.
There is no such avoidance. And Michael gave you a very good answer to
your charge of irresponsibility. The guide I linked to above, however,
is a work in progress attempt to do exactly what you have asked for.
The target is a lay audience of course, the peer reviewed journals are
where the legitimate scientific issues are hashed out.
Coby
Michael Tobis
> temperature- and CO2-wise) has happened many times in the past.
This is pernicious nonsense. There is no evidence in the paleoclimatic
record of CO2 concentrations increasing as fast as they are currently
doing, and there is unequivocal evidence that nothing of the sort has
happened in the last 600,000 years.
Also over the last 600,000 years at least, and probably much longer,
CO2 concentration has stayed within a range that it has now clearly
exited.
See http://www.globalwarmingart.com/wiki/Image:Carbon_Dioxide_400kyr_Rev.png
(many thanks due to Dragon's Flight, er, Robert) and data referenced from there.
As Daniel Moynihan said once, you are entitled to your own opinions
but you are not entitled to your own facts.
mt
Coby Beck
> Roger Coppock wrote:
>
> > > Steve Adams wrote:
> > >
> > > In my university, I was taught that a
> > > theory is valid only if can legitimately
> > > explain away any contradiction.
> >
> > Then you were taught incorrect statements at your
> > university. Quantum Mechanics, for just one example
> > out of many possible cases, is full of unexplained
> > contradictions. Yet, it makes valid predictions.
>
> I'll buy your QM example. Historical precedent can satisfy me in the
> face of mathematical inconsistencies. Human-Induced Global Warming
> (HIGW) theory and climate modeling, though, have neither a lengthy
> record of predictive success nor an uncontested mathematical basis (in
> my opinion).
Did you know that this history is over 100 years long?
http://www.aip.org/history/climate/timeline.htm
In terms of "uncontested mathematical basis" you should be more
specific.
> HIGW proponents are asking us to believe that man represents a
> paradigm shift in the way we must think about global climate. And
> because man is such an dominant phenomenon on the planet, and in the
> face of events such as glacial melting and ultra-violent storms (things
> not seen in recorded history), that becomes a plausible belief.
> Skeptics, however, have shown that what is happening now (at least
> temperature- and CO2-wise) has happened many times in the past.
Really? Can you elaborate? AFAIK, there are very few historical
precedents for what is hapening now, eg the PETM event, and what's more
these precedents are very dire as predictions of where we are headed
now.
> Nothing, so far, is new. It is, therefore, incumbent on HIGW proponents
> to dispel each skeptical argument.
I happen to disagree with this as a general approach to pollution
controls. It should be proven that CO2 emissions are harmless before
we should decide to produce them at will.
> Because I am tempted to believe that man is having at least some
> impact, my threshold of convincability is relatively low. What I would
> like to see is Professor Mann's tree ring analysis applied to a 1000
> year data set that includes as much of the 1900's as possible. The
> debate over the "hockey stick" has deteriorated into a mathematical
> pissing contest of subtle proportions. If the HIGW community would join
> with skeptics to promote funding an effort to "top off" the data set by
> coring trees for that data, a pittance compared to implementing Kyoto,
> the world would see a more truthful representation of the planet's
> temperature history for the past 1000 years. Is that too much to ask?
Why do you consider this to be the most important element of the
debate? Knowledge of the past can be very informative, but it is
neither explanatory of the present, nor predictive of the future.
Coby
Michael Tobis
and he addresses the aerosols. There are some flaws in the argument,
but he can't be accused of missing the point altogether.
For what it is worth, I agree with Lindzen's criticisms on pp 14 ff;
the agreement between model and observation displayed is rather
misleading and is probably overstated. The way climate models are
tuned is pretty ad hoc and casual, and there is probably some informal
tuning to the observational record in the mix by now. On the other
hand, page 10 overstates the problem. What different models mean by
their cloud number do not represent the same quantity in a phsyical
sense, but rather should be treated as unfirmly scaled, based on what
other parts of the system do with that number. You will see that if
they were all scaled to the same mean, the disagreement would not
appear to be as horrifying as presented.
I think the quality of the models is intermediate between the
intuitive impressions given by Lindzen's page 10 and his page 14, and
I hate to see this particular topic so polarized, when in my view the
truth lies squarely in the middle.
I am amazed he still thinks his "iris" idea is in play, though.
What is most alarming is the new leap from optimism to pessimism. "If
they are right it's too late and we are all doomed anyway" attitude
that Lindzen apparently feels comfortable adopting.
Mr. Gore discusses this latest rhetorical trick briefly in his recent
movie, but not imho sufficiently effectively. The world needs to find
a strong response to this rather sinister trick. Words fail me (for
now at least).
mt
James Annan
> Let's be fair. Lindzen does address the thermal inertia of the ocean,
Where? I've not seen it.
> and he addresses the aerosols.
Ony with the ridiculous suggestion that since their effect is uncertain,
it should be assumed to be zero.
James
Max Randor
of years ago - does not mean that HIGW is not happening - it just means
that it can happen.
Previous occasions might have been caused by methane hydrates
destabilising or forest fires the size of continents. Currently the
increase in CO2 is caused by the burning of fossil fuels - laid down
millions of years ago - probably made from carbon dioxide that was
doing what it is doing now. This time we are the cause, us humans. The
people who have found that carbon dioxide has been this high before
millions of years ago and that the temperature was really high then to
- they know that HIGW is happening - and their research supports it.
Otherwise what you said is interesting.:-)
steve
Well, I asked for it and BOY did I get it!
First, apologies are in order. To Michael, for inadvertantly
insulting him, gratuitously or otherwise, and for publishing
"pernicious nonsense" by inadvertantly and errantly stating that CO2
levels had reached similar levels many times in the past. As one of the
leading braintrusts of our time said, "DOH!" To all, for choosing words
that were emotionally charged. I have been reading many skeptic blogs
lately. These are folks who, in my opinion, raise legitimate points but
get no "airtime" in the debate. Their frustration is contagious.
Second, my goal in posting here is not to change Human-Induced
Global Warming (HIGW) proponent's minds but to educate myself. If my
posts are too elementary for the desired level of discourse for this
blog, let me know. I'll back off. Otherwise, I'll be glad to launch the
skeptic's "clay pigeons" for you to shoot at. Most of it may be old hat
while I boot myself up. Now and again, though, I may run across
something new. The result will be instructive not only to me, but to
others who visit this blog seeing civil, productive Q & A on this
issue. Lord knows, you might even change my mind.
Lastly, as I have been reading a lot, I can't always remember the
source of my statements. No obfuscation was meant. Just poor
bookkeeping. If invited to continue posting, I'll try to do better.
Mr. Moderator, your call.
Steve
Michael Tobis
No, in fact that is almost certainly correct! That's not the same as
what you said that I cal;ed pernicious nonsense.
CO2 levels were certainly much higher in the very distant past. In the
deepest past (about 4 billion years), the atmosphere was, as on Mars
and Venus, mostly CO2, which accumulates from volcanic emissions over
long times unless life is there to remove it.
Even after life arose there is strong geological evidence that there
were times when CO2 levels were much higher than today.
The process by which CO2 equilibrates on very long time scales is quite
an interesting one, actually. Dan Schrag of Harvard has an amazing talk
comparing the histories of Earth, Mars and Venus that sheds some light
on this. I tried to find his slides to no avail, but here's an article
about the talk:
http://www.news.harvard.edu/gazette/2005/10.06/09-climate.html
So what was pernicious? You said
> that what is happening now (at least
> temperature- and CO2-wise) has happened many times in the past.
What is, as far as anyone knows, totally without precedent is the rate
of change we are seeing in CO2, and the rate of change we are expecting
of temperature.
It is nonsense to imply that what we are seeing could possibly be
cyclical. That is excluded by the evidence.
Much as I would like to believe otherwise, it's clear that this fact
doesn't prevent paid agents of some of the less responsible energy
companies from implying otherwise, though they are usually careful not
to actually say it. Nor does it prevent the libertarian and right-wing
magazines from making the intended inferences, nor well-intentioned
people from believing them.
It just ain't so. The contemporary CO2 signal is not cyclical. It's
about as impossible as anything impossible can be.
Could the temperature signal be cyclical? It becomes less plausible
with every year, but there is a sliver of statistical possibility left,
if the temperature signal is examined in isolation from the greenhouse
forcing. That is, if all knowledge is statistical, and physical
knowledge is treated as worthless, there is still a small, purely
statistical and observational possibility that the temperature
variation is independent of the CO2 and just happens to be taking a
warm excursion.
However, that sliver is vanishingly small once you do accept the
physical understanding of how the surface temperature of planets with
atmospheres comes to be. This understanding is not new, and the basic
principles were understood over 150 years ago.
I hope you don't think I'm quibbling. We need to speak precisely here.
The basic facts aren't that complicated, but they are under attack by
people who deliberately want to confuse the situation. So it's
necessary to say what's true and what isn't with some precision.
Yes, CO2 has been as high or much higher than today, in the very
distant past, and so have temperatures, (usually at the same time!).
CO2 has never before, as far as anyone knows, risen even a tenth as
quickly as it is now doing. So it is very wrong to say something like
"what is happening now has happened many times in the past".
mt
James Annan
> Second, my goal in posting here is not to change Human-Induced
> Global Warming (HIGW) proponent's minds but to educate myself. If my
> posts are too elementary for the desired level of discourse for this
> blog, let me know. I'll back off. Otherwise, I'll be glad to launch the
> skeptic's "clay pigeons" for you to shoot at. Most of it may be old hat
> while I boot myself up. Now and again, though, I may run across
> something new.
Make sure you have a look at RealClimate first (and indeed elsewhere on
the internet). Posts which simply repeat the same tired sceptic talking
points risk not being considered "constructive and/or interesting" by
the moderators, especially since the answers can usually be readily
found elsewhere.
James
Coby Beck
> Michael Tobis wrote:
>
> > Let's be fair. Lindzen does address the thermal inertia of the ocean,
>
> Where? I've not seen it.
pg 28 of the pdf in the OP he does say:
"In point of fact, the impact of man remains indiscernible simply
because the signal is too small compared to the natural noise. Claims
that the current temperatures are 'record breaking' or
'unprecedented', however questionable or misleading, simply serve
to obscure the fact that the observed warming is too small compared to
what models suggest. Even the fact that the oceans' heat capacity
leads to a delay in the response of the surface does not alter this
conclusion."
Though one could of course object that mentioning it is not really
addressing it.
That is followed immediately by:
"Claims concerning recent warming trends have been particularly
misleading. The records on the right are completely consistent with a
rapid rise from 1976 to 1986 and
almost no rise since. This would be more like what is referred to as a
regime change than a response to global greenhouse warming."
Which doesn't make sense but (Tim Lambert IIRC) someone suggested these
is a copy-paste-oops-forgot-to-edit of the same arguement he was making
over a decade ago.
Coby
James Annan
Coby Beck wrote:
>
> James Annan wrote:
> > Michael Tobis wrote:
> >
> > > Let's be fair. Lindzen does address the thermal inertia of the ocean,
> >
> > Where? I've not seen it.
>
> pg 28 of the pdf in the OP he does say:
>
> "In point of fact, the impact of man remains indiscernible simply
> because the signal is too small compared to the natural noise. Claims
> that the current temperatures are 'record breaking' or
> 'unprecedented', however questionable or misleading, simply serve
> to obscure the fact that the observed warming is too small compared to
> what models suggest. Even the fact that the oceans' heat capacity
> leads to a delay in the response of the surface does not alter this
> conclusion."
>
> Though one could of course object that mentioning it is not really
> addressing it.
"Lying about it" would seem to be nearer the mark. Even　back in 1988, Jim Hansen was doing a pretty good job, and his forecast has proved to be very good indeed.
James
Max Randor
shooting myself - but if it convinces you then great.
Coby Beck
> Coby Beck wrote:
>
> > - is Lindzen correct that 35% CO2 applies a forcing that is 75% of 2x
> > CO2?
>
> No.
>
> The CO2 rise alone will account for ln(1.35)/ln(2) = 43% of the effect
> of a doubling. Crowley gives the total GHG effect at about 2.4W/m^2,
> which would only be 75% of the doubling if a doubling was 3.2W/m^2. In
> fact it is about 3.7W/m^2, so a 35% increase in CO2 gives 54% of a
> doubling. So 75% is an overestimate of all GHGs, and note furthermore
> that this also ignores the cooling effect of aerosols (about 1W, making
> a total anthropogenic forcing of 1.4W or about 40% of a CO2 doubling).
Have you made a typo here: 2.4/3.7 = .65 Where does 54% come from?
> There also happen to have been a few unusually large volcanoes in the
> last couple of decades, without which a slightly greater warming would
> probably have been seen.
Aren't volcanoes accounted for along with the rest of aerosol forcing?
Coby
James Annan
> James Annan wrote:
>
>>Coby Beck wrote:
>>
>>
>>>- is Lindzen correct that 35% CO2 applies a forcing that is 75% of 2x
>>>CO2?
>>
>>No.
>>
>>The CO2 rise alone will account for ln(1.35)/ln(2) = 43% of the effect
>>of a doubling. Crowley gives the total GHG effect at about 2.4W/m^2,
>>which would only be 75% of the doubling if a doubling was 3.2W/m^2. In
>>fact it is about 3.7W/m^2, so a 35% increase in CO2 gives 54% of a
>>doubling. So 75% is an overestimate of all GHGs, and note furthermore
>>that this also ignores the cooling effect of aerosols (about 1W, making
>>a total anthropogenic forcing of 1.4W or about 40% of a CO2 doubling).
>
>
> Have you made a typo here: 2.4/3.7 = .65 Where does 54% come from?
I was doing ln(1.35)/ln(2) for CO2 alone. Crowley's 2.4 includes non-CO2
GHGs (with a significant contribution from methane).
>
>>There also happen to have been a few unusually large volcanoes in the
>>last couple of decades, without which a slightly greater warming would
>>probably have been seen.
>
>
> Aren't volcanoes accounted for along with the rest of aerosol forcing?
They are generally considered separately (eg Crowley's data set). For
one thing, they are ejected much higher into the atmosphere and have
somewhat different effects, and for another it allows separation into
natural (volcanoes+solar) v anthropogenic (GHG and aerosols).
James
EliRab...@yahoo.com
decade you clearly mislead us about the danger we were confronting.
You served a political movement that had no interest in the reality and
were willing to accept their applause and support. Thanks to following
your advice we now must take more radical, costly and disruptive
actions. You have lost all credibility and in an just world you would
lose your position, wealth and honor. Go.
Eli (a rabett in exile)
steve
1) Ice cores in the Antarctic seem to show that CO2 concentrations lag
temperature by ~900 years. Possible?
2) Some hundred year temperature records from around the U.S. show a
flat trend. Obvious question, if warming is global, why do widely
separate sites record no warming trend?
3) If average temperatures do climb, say, 1degree C over this century,
there are benefits. Do the consequences outweight them?
I also have a question and a specuation. Question: how is the
atmospheric CO2 measured today? I assume instruments make direct
measurements at altitude. Speculation (my own): since we have no direct
atmospheric CO2 measurements of the past (like today), is it possible
that CO2 concentrations have been as high as they are today during
warming cycles? The idea being that due of atmospheric dynamics,
launching large amounts of CO2 into the amosphere can occur quickly
while CO2 settling (like into ice cores) is dampened by those same
atmospheric dynamics. The atmosphere would act like a low pass filter
on ice core CO2 concentrations by spreading out any spike in CO2 over
time.
Steve
Eli Rabett
1. There may be a delay between the onset of warming and the increase
of CO2 concentrations in ice ages (the data is equivocal to an extent
but interesting and worthy of attention). The delay is usually quoted
as of the order of 500 years not 900. However, this is what you would
expect, given that the major forcing coming out of ice ages is orbital.
Even with increased orbital forcing it will take some time for ice to
melt and the oceans to warm. As the oceans warm and ground is exposed
more CO2 will be released. This released CO2 will, in turn, amplify
the warming. In this case the external forcing is imposed by orbital
changes and the released CO2 is a positive feedback. In much the same
way fossil fuel burning is an external forcing and the smaller
associated direct warming increases atmospheric water vapor which acts
as a positive feedback. There was a recent paper showing that
anthropic driven increases in CO2 concentrations and their associated
warming have lead to increased natural CO2 emissions, a further
positive feedback, and consistent with any lag in CO2 concentrations
coming out of ice ages.
2. Is a bit of a tangle. First it is well known that there is
correlation between the climate of widely separated regions. These are
known as teleconnections. Given wind patterns this is not so
surprising. Second, given a system with some variance and say 500
measurement points, chance says that at least some of them would oppose
the general trend even without there being any physical connection.
Third, models show that the largest early temperature effects will be
in far northern latitudes, not at mid-latitudes. In short, this is the
reddest of herrings.
3. Another multiple red-herring. First, best estimates of the
temperature rise by 2100 range from 2-5 C
(http://en.wikipedia.org/wiki/Global_warming). Postulating a 1 C rise
is already an attempt to minimize the problem. Second, there is a
long, inherent delay in the climate system associated with the heat
capacity of the oceans. Any temperature rise by 2100, implies a
further rise into the 22nd century. For 2-5 C rises, the increase in
mean sea level alone costs enough land to make it more than economic to
start taking significant actions today. Of coarse, the sea level rise
itself has a lag of a century or more. I see you are of the what has
posterity ever done for me school, or perhaps the aliens will descent
from space and save/kill us all persuasion.
Eli (a Rabett in exile)
Coby Beck
> OK, here are a couple of pigeons:
Steve, my site was designed just for you!
http://illconsidered.blogspot.com/2006/02/how-to-talk-to-global-warming-sceptic.html
> 1) Ice cores in the Antarctic seem to show that CO2 concentrations lag
> temperature by ~900 years. Possible?
http://illconsidered.blogspot.com/2006/02/co2-lags-not-leads.html
> 2) Some hundred year temperature records from around the U.S. show a
> flat trend. Obvious question, if warming is global, why do widely
> separate sites record no warming trend?
http://illconsidered.blogspot.com/2006/06/some-sites-show-cooling.html
> 3) If average temperatures do climb, say, 1degree C over this century,
> there are benefits. Do the consequences outweight them?
http://illconsidered.blogspot.com/2006/02/whats-wrong-with-warm-weather.html
> I also have a question and a specuation. Question: how is the
> atmospheric CO2 measured today? I assume instruments make direct
> measurements at altitude.
Details can be had here:
http://cdiac.esd.ornl.gov/trends/co2/sio-mlo.htm
> Speculation (my own): since we have no direct
> atmospheric CO2 measurements of the past (like today), is it possible
> that CO2 concentrations have been as high as they are today during
> warming cycles? The idea being that due of atmospheric dynamics,
> launching large amounts of CO2 into the amosphere can occur quickly
> while CO2 settling (like into ice cores) is dampened by those same
> atmospheric dynamics. The atmosphere would act like a low pass filter
> on ice core CO2 concentrations by spreading out any spike in CO2 over
> time.
CO2 in the atmosphere is globally well mixed on time scales of a few
years so the air trapped in ice cores will not be as you describe.
Lowlying areas very close to CO2 sources can have very high local CO2
concentrations, such as areas right around volcanic venting. This is
not an issue at the sites in Greenland and Antartica where ice core
sample are taken.
What is technically possible is that short lived bursts of global CO2
elevation are smoothed out of ice core samples due to the coarseness of
the record, many centuries to a few thousand years between samples. I
think, ignoring the question of where such a spike would have come
from, a 35% jump over 150years such as today would look like if we
stopped all emissions instantly, might not show up. But we can't
ignore the question of where it would come from.
Coby
crandles
> Any temperature rise by 2100, implies a
> further rise into the 22nd century. For 2-5 C rises, the increase in
> mean sea level alone costs enough land to make it more than economic to
> start taking significant actions today. Of coarse, the sea level rise
>
> Eli (a Rabett in exile)
Do you have a citation for this? Sounds like a good way to show whether
the effects of the low end of the response range are serious. Of
course, there are problems: Is the land valued at ocean front prices
without taking account that other land will go up in value to ocean
front prices... Are those 'significant actions' necessarily in Kyoto
style preventing CO2 increases or is adaptation/preparing to adapt more
appropriate?
Raymond Arritt
> OK, here are a couple of pigeons:
I'll grab my shotgun.
> 1) Ice cores in the Antarctic seem to show that CO2 concentrations lag
> temperature by ~900 years. Possible?
It's instructive to change "lag" to "lagged". Increased CO2 can both
cause warming, and be an effect of warming. Therefore a positive
feedback can occur in which increased CO2 causes warming, which causes
higher CO2, which causes more warming, etc.
> 2) Some hundred year temperature records from around the U.S. show a
> flat trend. Obvious question, if warming is global, why do widely
> separate sites record no warming trend?
The word "global" means globally averaged, not globally uniform. We
expect average temperatures to rise. But some places will warm more,
some will warm less, and others may even cool depending on how climate
interacts with geography. For example our group proposed a mechansm
that could lead to reduced warming in the central U.S.:
http://www.agu.org/pubs/crossref/2004/2004GL020528.shtml
(Warning: this is somewhat speculative and needs to be confirmed in
more models.)
> 3) If average temperatures do climb, say, 1degree C over this century,
> there are benefits. Do the consequences outweight them?
As you may imagine this question is a topic of much research. The
prevailing view as summarized in the IPCC Third Assessment Report is
that as warming becomes greater, the costs increasingly outweigh the
benefits. See the Summary for Policymakers for discussion:
http://www.grida.no/climate/ipcc_tar/vol4/english/005.htm
(see esp. "Question 3")
> I also have a question and a specuation. Question: how is the
> atmospheric CO2 measured today? I assume instruments make direct
> measurements at altitude. Speculation (my own): since we have no direct
> atmospheric CO2 measurements of the past (like today), is it possible
> that CO2 concentrations have been as high as they are today during
> warming cycles? The idea being that due of atmospheric dynamics,
> launching large amounts of CO2 into the amosphere can occur quickly
> while CO2 settling (like into ice cores) is dampened by those same
> atmospheric dynamics. The atmosphere would act like a low pass filter
> on ice core CO2 concentrations by spreading out any spike in CO2 over
> time.
In reality there isn't much of a "low-pass filter" due to atmospheric
dynamics as such. You can even see a seasonal cycle in the measurement
record that tends to follow the Northern Hemisphere growing season.
Eli Rabett
Michael Tobis
> Of
> course, there are problems: Is the land valued at ocean front prices
> without taking account that other land will go up in value to ocean
> front prices
Sorry, you are taking a grim joke much too literally here.
Do you really suppose that the new coastline opening up behing the
newly submerged beaches is actually going to be attractive? The old
beachfront condos will magically disassemble themselves, leaving no
dangerous debris? The muddy, eroding bluffs will smooth themsleves to
a modest pitch, and the gentle sands will happily climb up them?
These processes take a very long time. After a major sea level
increase is under way there would be no sandy beaches except where
they are constructed, and it seems unlikely that anyone would bother
to construct a lot of them while the sea level keeps rising.
littoraly yours,
mt
James Annan
You've got to be joking!
The selfsame economics which you denounce for not caring past the
multidecadal time scale, also means that coastal engoneering projects
are routinely planned and implemented on a decadal(ish) planning
horizon. People build on and (try to) protect beaches for the sake of
this year and next's tourists, not what might happen several centuries
hence (one counterexample might be nuclear water repositories, but these
are very much the exception).
You talk about it as if it is going to happen in front of your eyes. But
no-one will ever notice it happening, any more than anyone remembers how
much lower sea level was in the last ice age. How long do you imagine
these beachfront condos will last anyway?
James
James Annan
> coastal engoneering projects
> nuclear water repositories,
Doing well with the typos!
Sorry,
James
steve
someone's/everyone's feedback on. It is
http://www.intellicast.com/DrDewpoint/Library/1295/. It is a bit dated.
I queried for an update but my email bounced.
It does not appear to take a stand on CO2 one way or the other but
seems to enforce the idea that solar activity is the primary driver in
warming. A very interesting topic is the rapid disappearance of surface
temperature measurement sites around 1989 and an abrupt step function
and upward trend in average surface temperature thereafter.
It will also be interesting to see if the decrease in solar activity
combined with a reversal of the Pacific oscillation will bring cooling
over the next few years.
Steve
William M Connolley
On Sun, 11 Jun 2006, steve wrote:
> http://www.intellicast.com/DrDewpoint/Library/1295/. It is a bit dated.
This is pretty well a collection of std.skeptic talking points. The MSU stuff is
wrong as is (I think) pretty well all of it. See RC (or Coby) for the details...
-W.
--
This message (and any attachments) is for the recipient only. NERC is subject
to the Freedom of Information Act 2000 and the contents of this email and any
reply you make may be disclosed by NERC unless it is exempt from release under
the Act. Any material supplied to NERC may be stored in an electronic
records management system.
Michael Tobis
Having actually seen Miami Beach argue for some years and then import
at great expense a great quantity of sand to cope with a relatively
small retreat of the shoreline, I question whether this sort of thing
is "routine" or un-noticeable. (Admittedly, it worked strikingly well,
economically, but Miami Beach has some unique advantages.)
I think the question you raise is equivalent to whether the entire
world will be geo-engineered. As far as beaches go, perhaps we will
manage it, but even so, the idea that this means some shoreline will
be replaced by other shoreline with marginal net cost strikes me as
wishful thinking. Even if we remain well-enough organized to scare up
the price for every inch of shoreline, the question of how to arrange
for it to happen presents great difficulties.
I think the lesson of New Orleans is that in a real-estate-driven
economy, people will not let go of their property easily. This means
that they will preserve their investment desperately. But once a
twenty story building is abandoned to the sea, will people bother to
pull them down? That depends on how well other things go. In America,
the structures will likely be neatly contrived to be in the possession
of a bankrupt and soon-to-be-defunct organization at the time of their
abandonment.
You live somewhere that buildings are considered temporary. I live
somewhere that they are considered disposable. There are astonishingly
fine structures, some quite large, abandoned and rotting all over the
south side of Chicago. Okay, that one is demographic, but there is a
similar case that can be attributed to climate change. Mississippi
riverfront towns in a state of incipient Romanesque ruin, a
consequence of increased amplitude and frequency of flooding in recent
decades, are commonplace. I find it likely that the same will be true
of the Atlantic coastline of the US someday.
Another possible outcome is the Dutch system. As this would amount to
a general tax to protect specific moneyed interests (socialism for the
wealthy as I heard one fellow describe America) it's not an
implausible outcome in an American culture not dramatically changed
from today's. But a dike-front condo will have less appeal than a
beachfront one.
In any case, natural ocean beaches will cease to exist, and so the
cost of a beachfront will increase relative to its value. It's hardly
a break-even situation even if the rate of change remains slow enough
to plan for tourism.
Also, you should note that the gravitational stability of a natural
sandy beach is marginal as a consequence of how it came to exist in
the first place, so that a small increase in sea level leads to a
large retreat of the shoreline.
Finally, though I think for some reason this is more common in America
than elsewhere, much of the beachfront is actually on sandbars,
shallow islands which will disappear entirely, notably including Cape
Hatteras, Galveston, Hilton Head (I think), Miami Beach, Cape
Canaveral.
Nice survey article here:
http://www.whoi.edu/institutes/coi/viewArticle.do?id=2484
mt
gerh...@aston.ac.uk
> GHGs (with a significant contribution from methane).
Coby and me have been discussing this over on his blog. I don't
understand your answer.
You said that ln(1.35)/ln(2)=43% (which is the same my spreadsheet
gives) and that that's CO2 forcing for a 35% increases in CO2
concentration as a fraction of CO2 forcing for a 100% increase in CO2
concentration.
What's the 54% however?
Strangely enough, when I (by mistake) typed in 35/65 I got 54%. But 35%
is for concentration, and 65% for forcing (2.4/3.7=0.65).
Also, as I mentioned over on Coby's blog, I wonder whether your figures
might be slightly out of date. After all 75% would mean that forcing is
now somewhere between 2.7 and 2.8 W/m2 and the IPCC report is now about
half a decade old.
James Annan
> Hmmm.
>
> Having actually seen Miami Beach argue for some years and then import
> at great expense a great quantity of sand to cope with a relatively
> small retreat of the shoreline, I question whether this sort of thing
> is "routine" or un-noticeable. (Admittedly, it worked strikingly well,
> economically, but Miami Beach has some unique advantages.)
Actually importing sand (and doing nothing else to protect it) is
generally a poor choice, but I was talking more generally about beach
management and coastal defence which is certainly routine around the UK
and I imagine elsewhere in the world. Given the extent to which my local
beaches have evolved within my life time, I'd be hard pressed to notice
40cm of sea level rise even if I did live another 100 years.
> I think the question you raise is equivalent to whether the entire
> world will be geo-engineered. As far as beaches go, perhaps we will
> manage it, but even so, the idea that this means some shoreline will
> be replaced by other shoreline with marginal net cost strikes me as
> wishful thinking. Even if we remain well-enough organized to scare up
> the price for every inch of shoreline, the question of how to arrange
> for it to happen presents great difficulties.
You are talking as if this whole scenario is going to be perceptible. As
such I find the whole conversation basically ill-founded!
An example: the south east coast of the UK is sinking by about
1.5mm/year, and has been doing so for ever, in human terms (isostatic
readjustment). The coast is fairly soft, so there are of course some
problems with erosion, land loss, difficult decisions regarding defence
versus managed retreat. AGW may add about 4mm/year on top, but this is a
quantitative, not qualitative change. It may (presumably, will) cost
some extra money overall and tip the balance more towards retreat rather
than defence, but it's not as if the sky is going to fall in.
James
James Annan
>>I was doing ln(1.35)/ln(2) for CO2 alone. Crowley's 2.4 includes non-CO2
>>GHGs (with a significant contribution from methane).
>
>
> Coby and me have been discussing this over on his blog. I don't
> understand your answer.
>
> You said that ln(1.35)/ln(2)=43% (which is the same my spreadsheet
> gives) and that that's CO2 forcing for a 35% increases in CO2
> concentration as a fraction of CO2 forcing for a 100% increase in CO2
> concentration.
>
> What's the 54% however?
Um...sorry...I dunno, and now I see what Coby was getting at. I'd
already given ln(1.35)/ln(2)=43% in the same paragraph, so probably the
54% was a typo or a careless mistake. A round 2W would be 54% of 3.7W,
so maybe that was a random sum I had performed somehow!
> Also, as I mentioned over on Coby's blog, I wonder whether your figures
> might be slightly out of date.
Certainly so (Crowley runs to 1998), but they are in the right ballpark
and saved me the trouble of trying to look up anything more precise!
James
Michael Tobis
> some extra money overall and tip the balance more towards retreat rather
> than defence, but it's not as if the sky is going to fall in.
Oh, true enough. I was responding to the idea of a major, rapid sea
level rise, order a few meters, which is what will happen when the
Greenland and/or the West Antarctic ice sheets fail. Most likely we
will not live to see it, as I understand the state of deliberations on
this matter.
The question raised was whether costs of loss of beachfront would be
balanced by an increase in formerly-inland property values, whenever
it happens. I think that's completely implausible no matter when it
occurs, and that's all I was saying in this context.
Admittedly, the true economic theory point of view is to say that
these events are so far in the future as to be negligible in
present-day calculations.
To get back to my hobby horse, I am confident that people in the
future wiill not see it that way.
It is within the realm of possibility that the Greenland ice sheet is
the glacial equivalent of a dead man walking already, or will be soon
enough. Should this figure into our deliberations, if the cause is
contemporary and the consequence is centuries in the future? Are we on
sound moral footing to commit our descendants to this problem?
mt
Eli Rabett
Much of the original work on climate change driven sea level rise was
done from the viewpoint of those involved in coastal engineering
projects http://users.rcn.com/jtitus/ for a good start
crandles
area where the coast is being eroded, I do not expect the new coastal
land to be the most desirable. (I mentioned other land not the new
coastal land.)
The price of land depends on supply and demand. In demand terms, the
ratio of highly valuable/desirable land to less desirable land will I
think depend more on the ratio of rich people to not so rich people
than on the physical properties of the land. On the supply side, there
is less land with desirable physical properties. Therefore we can
expect higher prices for the new distribution of desirable land.
Looking at the value of land lost only is a clear underestimate of the
problem. To continue that theme, I think the land lost should be valued
at some sort of average price of land rather than using ocean front
prices. If you can consistently choose an approach that clearly
underestimates the problem at all stages and still shows the problem is
serious enough to do something about, then it becomes a powerful
argument. If not, then so be it. There is then a need to take an
approach that is more sophisticated so that it does not underestimate
the problem so much.
I am trying to find out the quality of the argument before using it. I
am not trying to make a grim joke.
Michael Tobis
> I think you are inferring something that I didn't mean to imply. In an
> area where the coast is being eroded, I do not expect the new coastal
> land to be the most desirable. (I mentioned other land not the new
> coastal land.)
Hmm, ok, but if you reread what you said you can see why I misread it
that way.
> The price of land depends on supply and demand. In demand terms, the
> ratio of highly valuable/desirable land to less desirable land will I
> think depend more on the ratio of rich people to not so rich people
> than on the physical properties of the land. On the supply side, there
> is less land with desirable physical properties. Therefore we can
> expect higher prices for the new distribution of desirable land.
Yes, and taking this reasoning to a logical conclusion, if the land
somehow shrinks to a square kilometer (NB - I do not claim this is
possible, this is just for argument's sake), it will be immensely
valuable. But that is not wealth, that is inflation.
Similarly, if the atmosphere becomes too polluted to breathe in the
cities, a market for bottled air emerges. Does that mean the world is
better off? We already count bottled water as wealth.
How to measure genuine well-being? I don't know. Economists seem to
claim they know, but I've never found their approaches compelling.
Global change problems require that we think about this carefully.
> Looking at the value of land lost only is a clear underestimate of the
> problem. To continue that theme, I think the land lost should be valued
> at some sort of average price of land rather than using ocean front
> prices.
It's largely highly built-up land, and much of it has considerable
irreplaceable cultural value and considerable very hard to replace
ecological value, so this is a pretty severe underestimate.
> If you can consistently choose an approach that clearly
> underestimates the problem at all stages and still shows the problem is
> serious enough to do something about, then it becomes a powerful
> argument. If not, then so be it. There is then a need to take an
> approach that is more sophisticated so that it does not underestimate
> the problem so much.
That's reasonable, but I'm afraid it isn't very helpful. It's not hard
to construct a lower bound that is trivial, nor an upper bound that is
cataclysmic.
One important question to ask is which way the burden of proof should
lie.
mt
crandles
Michael Tobis wrote:
> crandles wrote:
> > I think you are inferring something that I didn't mean to imply. In an
> > area where the coast is being eroded, I do not expect the new coastal
> > land to be the most desirable. (I mentioned other land not the new
> > coastal land.)
>
> Hmm, ok, but if you reread what you said you can see why I misread it
> that way.
>
I tried to phase it in a way that could be taken as I did imply it even
if I didn't mean to.
>
> > The price of land depends on supply and demand. In demand terms, the
> > ratio of highly valuable/desirable land to less desirable land will I
> > think depend more on the ratio of rich people to not so rich people
> > than on the physical properties of the land. On the supply side, there
> > is less land with desirable physical properties. Therefore we can
> > expect higher prices for the new distribution of desirable land.
>
> Yes, and taking this reasoning to a logical conclusion, if the land
> somehow shrinks to a square kilometer (NB - I do not claim this is
> possible, this is just for argument's sake), it will be immensely
> valuable. But that is not wealth, that is inflation.
>
Yes if you are interested in GDP growth, it is usually an inflation
deflated version you want and I think that is usually what is done with
GDP growth figures but I stand to be corrected on that. I think this is
what I am doing by suggesting some sort of average value of land. I am
certainly not trying to claim that the value of land lost is is not a
problem at all because other land will go up in value to the same total
value.
>
> Similarly, if the atmosphere becomes too polluted to breathe in the
> cities, a market for bottled air emerges. Does that mean the world is
> better off? We already count bottled water as wealth.
>
Measuring inflation where quality changes is a problem. The solutions
used may well be crude approximations but as James Annan pointed out a
crude approximation is better than nothing and does not necessarily
make it non-sensical.
>
> How to measure genuine well-being? I don't know. Economists seem to
> claim they know, but I've never found their approaches compelling.
> Global change problems require that we think about this carefully.
>
> > Looking at the value of land lost only is a clear underestimate of the
> > problem. To continue that theme, I think the land lost should be valued
> > at some sort of average price of land rather than using ocean front
> > prices.
>
> It's largely highly built-up land, and much of it has considerable
> irreplaceable cultural value and considerable very hard to replace
> ecological value, so this is a pretty severe underestimate.
>
I agree it is a severe underestimate. So, if the argument holds up, it
will be a very powerful one!
>
> > If you can consistently choose an approach that clearly
> > underestimates the problem at all stages and still shows the problem is
> > serious enough to do something about, then it becomes a powerful
> > argument. If not, then so be it. There is then a need to take an
> > approach that is more sophisticated so that it does not underestimate
> > the problem so much.
>
> That's reasonable, but I'm afraid it isn't very helpful. It's not hard
> to construct a lower bound that is trivial, nor an upper bound that is
> cataclysmic.
The 'so be it' was meant to imply that if you end up with that then it
isn't helpful one way or the other and you have to look for something
better. If you are fortunate(skillful?) enough to find a lower bound
that is not trivial then it is helpful.
>
> One important question to ask is which way the burden of proof should
> lie.
I think there is ample evidence to say there is a prima facia case that
GHG are harmful to the extent necessary to shift the burden of proof on
to those who do not want to decrease GHG emissions. (Much as I don't
like it, yes, I think it is that way originally. Q. Who is responsible
for deciding whether the side effects of a proposed medicine is not
worse than the disease? A. The people who want to sell the medicine.)
Great - but what happens next? Do I just sit and wait for the other
side to provide the proof that I demand? What if I think the other side
doesn't accept that they need to do this? Sounds like a recipe for
nothing to happen.
Anyway, I agree that which way the burben of proof should lie is
important. However, it is not as important as which way it, in reality,
appears to actually lie*. If I don't want nothing to happen, then I am
back to looking for powerful arguments in the way I described.
*That still doesn't cover it. If it appears that at some future date it
will be decided that the burden of proof did rest with the other side,
but the other side still does nothing about it....
James Annan
> One important question to ask is which way the burden of proof should
> lie.
I think it's important to question whether the concept of a "burden of
proof" should apply at all.
(Eg <http://julesandjames.blogspot.com/2006/02/detection-attribution-and-estimation.html>,
although the context there is a rather different one.)
James
Michael Tobis
The last section of the article provides interesting and disturbing if
no longer especially surprising evidence about the maturity of the
political process on such issues,
http://www.nytimes.com/2006/06/20/science/earth/20sea.html?8dpc=&adxnnl=1&pagewanted=all
(You may need to provide an email address to read, or pick up today's
Times at a newsstand.)
mt
James Annan
> A relevant article on long-term beach erosion, especially in Florida.
>
> The last section of the article provides interesting and disturbing if
> no longer especially surprising evidence about the maturity of the
> political process on such issues,
>
> http://www.nytimes.com/2006/06/20/science/earth/20sea.html?8dpc=&adxnnl=1&pagewanted=all
>
I've not read the underlying report, but I'd bet dollarss to doughnuts
that its prediction of 1 in 4 houses lost is based on (a) the most
exaggerated emissions scenario they could find (b) a highish estimate of
the sea level response to those emissions (c) conflating the losses due
to coastal erosion and natural sea level rise, with the AGW sea level
rise component.
If anyone wants to prove me wrong...
James
(but I'm off for a week or two)
Eli Rabett
The elevation of the barrier islands are pretty much under 1.5 meters.
They are maybe a couple of hundred meters to maybe a km wide. These
barrier islands cover pretty much all of the US east coast from Florida
to New York. So no, it is not so hard to imagine that a fairly small
sea level rise coupled with rough seas from a storm could wipe them
out.
Eli Rabett