American Physical Society on climate change

[Gokul43201]

... there was the temperature rise prediction for the first decade of 2000-2010.

vanesch, could you please cite some papers that make this prediction?

I'm also not sure exactly what you mean by erroneous hockey stick. Was the hockey stick any differently erroneous than say, Newtonian mechanics (in principle)?

 

[mheslep]

vanesch, could you please cite some papers that make this prediction?...

If I may -
Hansen et al '88 must be one of the more famous. See figure 2 with Hansen scenarios A,B,C. Scenario A shows ~0.4C rise '00 to '10, B roughly the same.
A: "the assumed annual growth averages about 1.5% of current emissions, so the net greenhouse forcing increases exponentially".
CO2 emissions increased 28% in the 14 year period '90 through '04, so AFAICT scenario A reflects Hansen's preconditions, though Hansen stated in the 90's that B was the closest.
http://www.pnas.org/content/103/39/14288.full.pdf+html

 

[Gokul43201]

From that paper:

Because of this chaotic variability, a 17-year period is too brief for precise assessment of model predictions, but distinction among scenarios and comparison with the real world will become clearer within a decade.

If Hansen et al say a 17-year period is too brief for precise assessment, how is it fair to then make comparisons to an even briefer 10-year period of data?

Can you find a paper that talks about meaningful predictions for a 10-year period? We can then look at what that paper says.

 

[vanesch]

From that paper: If Hansen et al say a 17-year period is too brief for precise assessment, how is it fair to then make comparisons to an even briefer 10-year period of data?
Can you find a paper that talks about meaningful predictions for a 10-year period? We can then look at what that paper says.

I had indeed Hansen's paper in mind, as this was discussed in the Earth forum. I agree of course that "climate predictions over 10 years" are a bit short, but then a lot of fuzz was made about the quick rise in the 1980-1990-ies. So if 10 or 20 years are sufficient to "prove beyond doubt" the *dramatic* heating, then it should be worrisome that in the next 10 years, this is contradicted. Especially because the dramatic rise of the last decades was also in part used to estimate the "feedback amplification" for the CO2 forcing.

This is why it will only be possible to have any kind of real scientific certainty of any claim about climate change only at least 30 to 50 years from now. Anybody who claims anything with "scientific certainty" before that (theory, prediction, and significant experimental verification) is taking his working hypothesis for a fact. You say it yourself: even 17 years is not enough. "Climate change" has been with us since the 1990-ies. If models are made up now, and if their predictions need testing for 30 years, then we cannot have the typical "model prediction + data falsification" before 30 years or so from now. Only then, if the predictions and the data are coincident, we can start to have some form of scientific certainty.

We have no scientific certainty that the Higgs exists. Only when sufficient data will show it in the LHC, we will know with some form of scientific certainty. A climate model that makes any prediction *now* will need at least 30 years for it to be tested against noisy data. Before that, we cannot scientifically be certain.

The other part of the hockeystick that was "misleading" was the very flat part in the past. It showed the striking contrast between the sudden rise in the last decades, to an almost flat temperature record for the last 1000 years or more. I don't have to dig up the entire discussion, it is very well resumed in the wiki article: http://en.wikipedia.org/wiki/Hockey_stick_graph and has been discussed over and over in the Earth forum. I know that wiki is not a scientific journal, but I can't write any better summary than what's written there. I take it that the discussion is fair, as it corresponds to things I've seen in different places.

Let us not forget what was the purpose of the hockey stick. It was not to show that there has been a warming during the last several decades. I don't think anyone can deny this - it is in the instrumental record. The purpose of the hockey stick was to demonstrate that what was happening in the last few decades (even the last century or so) was totally exceptional, an obvious deviation from the "natural course of things" in such an evident and dramatic way, that even a layman could evidently see that we were screwing up things.
If you have a flat curve for a thousand years, and then you see a dramatic and almost linear rise for the last century or so, then nobody has any doubts anymore. This is "scientifically established beyond doubt". What is happening now has never happened before, and it is not a 3 sigma effect. It is a 100 sigma effect. And that drama is almost completely absent in more detailled studies that have been done more recently.
Yes, there's still a temperature rise. Nobody is denying that. But the drama is gone.

But please, don't understand me wrong. I'm not saying that there is no warming. I'm not saying that there is no AGW, or that there is not going to be any dramatic AGW. This is not my point. My point is that the "scientific certainty" that has been displayed, and that has been used and widely published and communicated, was wrong.

If you look at the two plots in the wiki article, the upper one the famous "hockey stick", and the lower one, more recent and more thorough studies, then it should be obvious that the *power to convince* of the first is far more dramatic than the second, no ?

That said, if you ask for my personal opinion, if I have to bet anything, I would bet on AGW. Hey, I'm a strong proponent for nuclear power and AGW is one of my main motives. I think it is a very plausible hypothesis. But there's a difference between a "plausible hypothesis" and "a scientific reality". I think - to answer your other post - that there's a world of difference between the certainty I have that the sun will rise tomorrow (Newtonian physics) and that the temperature will rise with 6 degrees in 100 years. The last is only on the level of "I think the Higgs exists".

It might be that the Higgs doesn't exist. I would be surprised. I think it exists. But I keep open the possibility that it doesn't exist. I'm not "scientifically certain" that it exists. Only experiment will tell. It cannot be that at the sun will not rise tomorrow. I'm scientifically certain that the sun will rise tomorrow. If ever the sun doesn't rise tomorrow, then about everything I know is wrong.

 

[Andre]

...if I have to bet anything, I would bet on AGW. Hey, I'm a strong proponent for nuclear power and AGW is one of my main motives...

You're on. I bet against. But with all due respect you have a motive for that. Physical realities don't have motives. It's just there, whether we like it or not. Remember Richards Müller http://muller.lbl.gov/TRessays/23-Medievalglobalwarming.html :

would love to believe that the results of Mann et al. are correct, and that the last few years have been the warmest in a millennium.

Love to believe? My own words make me shudder. They trigger my scientist's instinct for caution. When a conclusion is attractive, I am tempted to lower my standards, to do shoddy work. But that is not the way to truth. When the conclusions are attractive, we must be extra cautious.

The short conclusion from my browsing around is:

the AGW radiation based hypothesis assumes a dry warming of around 1 degreeC dor doubling CO2 (MODTRAN). A wet warming (keeping relative humidity constant) would amount to some 1.4 degrees. This implies positive water vapor feedback already. Nevertheless the IPCC assumes 2-4 degrees per doubling, assuming a big extra feedback of which the albedo decrease from melting snow seems to be the main factor. But where the snow melts, is radiation a relatively small factor.

Moreover in the water vapor feedback to keep relative humidity constant, it can be calculated that this takes just about as much energy as was required to cause the extra warming.

And then there is the convection factor. Chiligar et al show that this process plays a very important role in energy distribution in the atmosphere. The numbers are not really important, important is that the IPCC reports completely neglect this effect. Sure they mention convection occasionally but it is never related to the energy distribution.

So without any further factors the IPCC working hypothesis does not add up in the first place. So why is kept up? Because of the wild isotope jumps in the Greenland ice cores, which are interpreted as about 10 degrees temperature change within a decade. Therefore we really need to understand what happened there. But whatever the outcome, can it repair the physical deficiencies of the working hypothesis?

So what is the actual expectation of the global temperature rise with doubling CO2?

Around zero degrees C, if Chilingar et al 2008 are right that increased greenhouse effect increase the convection rate, effectively removing the additional energy from the Earth surface to the mid- to higher trophosphere, where it can radiate out to space.

Between zero and one degree C, if you think that the increased IR radiation is more important than convection.

Between 1.0 and 1.4 degrees if you think that convection does not play a role and that somehow there is enough additional energy to get positive water vapor feedback for maintaining constant relative humidity, increasing the greenhouse effect.

Between 2-4 degrees if you think that there are not understood feedbacks that played a role in the ice age. Therefore it is very important to understand what we are seeing there in the ice cores and other records. I did that, I explain that in the Earth forums and my bet that is this a non option.

The next question is of course, how catastrohic would any amount of warming be? For that we should look at the Holocene Thermal Optimum between 9000 - 6000 years ago when the trees grew at the Arctic coast of Siberia. In this period the temperature was about 2-5 degrees warmer than today on the Northern Hemisphere. It was also the period that mankind left the caves and started societies. Possibly that this was the reason that the period was not called the Holocene Thermal Catastrophy.

I'm a great proponent of going nuclear to the maximum extent as well and get off the fossil fuels, but I think it is a very big mistake to use a non-option to propagate that. because when the truth has its boots on, all what has been accomplished will be lost, since the reason ceased to exist. It would even have been a much bigger mistake if that hypothetical warming would have been benificial rather than catastrophic. Therefore we must do the right things for the right reasons.

 

[vanesch]

You're on. I bet against. But with all due respect you have a motive for that.
[ ... ]So what is the actual expectation of the global temperature rise with doubling CO2?

Around zero degrees C, if Chilingar et al 2008 are right that increased greenhouse effect increase the convection rate, effectively removing the additional energy from the Earth surface to the mid- to higher trophosphere, where it can radiate out to space.

Between zero and one degree C, if you think that the increased IR radiation is more important than convection.

Between 1.0 and 1.4 degrees if you think that convection does not play a role and that somehow there is enough additional energy to get positive water vapor feedback for maintaining constant relative humidity, increasing the greenhouse effect.

Between 2-4 degrees if you think that there are not understood feedbacks that played a role in the ice age. Therefore it is very important to understand what we are seeing there in the ice cores and other records. I did that, I explain that in the Earth forums and my bet that is this a non option.

Ha ! So your bracket for "temperature increase predictions" one century from now, where the CO2 content of the atmosphere will have more than doubled if we don't do anything, is between something like 0 and 4 degrees. The IPCC says between 1.5 and 6 degrees.

None of you can claim these things with absolute scientific certainty, but I guess you can agree that 50 years from now, we will know better. Up to that point, everybody can have his/her favorite working hypothesis, with arguments in favor for it.

It will not be possible to claim with any scientific certainty that there is no AGW before that, and this has now been officialized with the multidecadenal oscillation: even if the temperatures start to fall in the next 2 decades, AGW proponents will still claim that this is no proof of lack of AGW. Now, if these oscillations are really there, then they are right: it is just stepping a few degrees back just to shoot up even faster after that. If these oscillations are not there, then we won't know before at least 2 or 3 decades that they aren't there and that they are just a sign of absence of AGW.

So we will have to live in any case with 2 or 3 decades of AGW doomsday thinking which has been officialised by so many scientific instances, that it is scientific career suicide to say anything else (and one won't be able to "prove beyond doubt" anything else for the next few decades). There is no career advantage to be gained by showing to have been right 30 years from now. Too many people have committed to AGW to be able to flipflop before the end of their careers. So we will have to sit that out in any case, even if there's not the slightest bit of AGW.

So given that in any case "social AGW" is now going to be a fact with which one will have to live for a few decades, let us just as well use that to promote any agenda one can have. The green parties do it already full steam ahead. It will have the additional benefit of solving partly the risk associated with a true AGW if ever this turns out to be there.
It's the thing to do when you want to achieve just anything. Say it fights AGW. You'll get it done, you'll get it funded, you'll get it promoted.
The only thing that won't be open is independent scientific inquiry. So I'd say that the only thing that is not a good idea is to become a good climate scientist in the next few decades, as the conditions won't be fulfilled to do serene work in that field

I say this half-jokingly, but in fact with some bitterness, because it is exactly the point I regret most in this debate: that scientific serenity is gone. The scientist in me finds it terrible, the opportunist in me tries to see it as an opportunity.

I'm a great proponent of going nuclear to the maximum extent as well and get off the fossil fuels, but I think it is a very big mistake to use a non-option to propagate that. because when the truth has its boots on, all what has been accomplished will be lost, since the reason ceased to exist. It would even have been a much bigger mistake if that hypothetical warming would have been benificial rather than catastrophic. Therefore we must do the right things for the right reasons.

In an ideal world, I'd agree with you. But if we can force nuclear power for a few decades on the basis of "social AGW", then that will be 3 decades more of nuclear power. People will have gotten used to it by then. The Chernobyl scare will belong to the past. The doomsday pictures of nuclear will have been washed away. We will have a new generation of people who didn't grow up with anti-nuclear propaganda by then, and even if at that point, AGW turns out not to be true, it won't matter, the habit will have been taken.

And, contrary to you, I still keep the possibility of genuine AGW - and not because I have "an agenda". In as much as I don't consider it as scientifically established beyond doubt, I *do* consider that there are several elements that indicate a warming, and I'm not enough of a climate scientist to contradict everything they say. I think even climate scientists wouldn't be able to sustain the AGW hype if it were *evidently clear* that there wasn't such a thing. That's good enough for me to keep open the possibility.

 

[Andre]

I understand and symphatize with the opportunist inside you, Vanesch, but I'm afraid things go always different than we hope it does.

Firstly, on the scientific side of AGW, If you're done with the interpretation of the paleoclimate proxies, it would become clear that there is nothing supporting the enormous temperature fluctuations during the Pleistocene and I'm more than happy to explain in the coming days. It would be clear, as I said before, that we can be certain what is was not (greenhouse gas forcing) but we are in the dark about what did it. That's simply refuting the last stronghold for a strong AGW effect. Take that with the uncertainty if climate warming is bad or good and the odds for climate catastrophe are infinitemisal small. Zero for me, other others may keep their options open.

Considering the social AGW, the idea that we could manipulate society into doing the right thing for the wrong reasons is noble but also rather dangerous. One has to consider why there are so strong incentives to propagate global warming. I will not litter these threads with non-scientific *motives* for that but I give a google hint: "enron", "cap and trade", "lehman", "Gore". Trying to do the right thing for the wrong motives is likely to do much more harm than you could begin to imagine. This cap and trade thing is the most anti-Robin Hood possible, steal from the poor to give to the rich. Nobody would even begin to think about going nuclear, since that's about as scary as AGW, of which you made no attempt to unexplain it.

There is only one way to solve these problems. Show humanity the tragical effects of groupthink like in 1789 (French revolution), 1917 (Russian revolution), 1933 (German *revolution*). unfrighten them. Try to free them of groupthink. Go rational and forget about fears. In a word: be honest.

 

[vanesch]

Considering the social AGW, the idea that we could manipulate society into doing the right thing for the wrong reasons is noble but also rather dangerous.

I didn't say that. I didn't say that one has to join the hype. I think simply that it is going to be unavoidable. In other words, no matter what data is going to show up, no matter what an individual is going to write, no matter what an individual is going to be able to do, we are bound to live in a society for the next few decades in which the AGW bogey man is going to be one of the leading motifs. I think we already reached the point of no return, so I think that professionally fighting this (not denying AGW, because no matter what you claim, I think this is not demonstrable right now either, but trying to point out that it is not yet a scientific certainty) is simply impossible and can only harm the individual who tries to do so.

So *given* this wave of unavoidable, well, dogmatism, one can just *use* it to drive home whatever agenda one has to drive home. Payday is still very far away. If AGW turns out to be right, then payday will never come. If AGW turns out not to be there, well, that's then maybe thanks to you and your initiatives to avoid it (similar to the year 2K bug disaster) !

 

[Amp1]

I have a question. Does the north polar ice cap cover the same or as much 9or more) area than it did 5 yrs age? 10 yrs ago?

 

[mheslep]

Just clik through the blog hyperbole to the NASA EO, linked in the blog 4th para.
http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=18012
Just states that the PDO is on the down (cooling) swing. The blog title is silliness.

 

[baywax]

Now I'm getting somewhere...

Story Published: Feb 29, 2008 at 12:37 AM EDT
Story Updated: Feb 29, 2008 at 12:53 AM EDT
New scientific studies suggest a trend that may have started in the late 1990s. The Earth may be cooling.
The Hadley Centre for Climate Change, part of the UK Met Office, tracks global temperature and shows a big drop in global temperature anomalies since January 2007. Based on the HadCRUT3 system of observed temperatures, global surface temperature anomalies have been trending down since 2001. January 2008 had the coldest anomaly since 1995.
Temperature anomaly is the difference between observed temperature and the average temperature for the same time over a period of years.

Closer to home, Dr John Christy of the University of Alabama, Huntsville, uses NASA data to track global temperatures. His latest report suggests that compared to seasonal norms, January 2008 was the coldest month since July 2006 and the coldest January since 2000.

http://www.nbcaugusta.com/weather/news/16011587.html

And the link from this story is...

http://hadobs.metoffice.com/hadcrut3/diagnostics/global/nh+sh/monthly.png

and here is where they get their info on snow and ice etc...

http://www.ncdc.noaa.gov/oa/climate/research/2007/snow0708.html

 

[Evo]

I've deleted the preceding posts, if there is a press release that can be verified it can reposted.

From researching this, it seems it is based on the solar minimum we are currently in and debate on how long it will last and what the consequnces would be if it continued as in the solar minimum known as the "Maunder Minimum" that caused the "Little Ice Age" starting in the mid 17th century.

 

[baywax]

I've deleted the preceding posts, if there is a press release that can be verified it can reposted.

From researching this, it seems it is based on the solar minimum we are currently in and debate on how long it will last and what the consequnces would be if it continued as in the solar minimum known as the "Maunder Minimum" that caused the "Little Ice Age" starting in the mid 17th century.

Thanks Evo. Sorry for the hype. Its snowing here.!

 

[Evo]

Thanks Evo. Sorry for the hype. Its snowing here.!

I know what you mean, we basically had no summer, our daily temperatures are ranging 10-20 degrees lower than average. There were very few days that we even hit average. Spring was cold and well below average also.

 

[baywax]

I know what you mean, we basically had no summer, our daily temperatures are ranging 10-20 degrees lower than average. There were very few days that we even hit average. Spring was cold and well below average also.

Did you see my post 46? Seems on the up and up. Fairly reviewed. Perhaps things are cooling down for us.

 

[Art]

I know what you mean, we basically had no summer, our daily temperatures are ranging 10-20 degrees lower than average. There were very few days that we even hit average. Spring was cold and well below average also.

Same here in Ireland. We had the wettest summer for 170 years and in Ireland that's saying something!

 

[baywax]

Same here in Ireland. We had the wettest summer for 170 years and in Ireland that's saying something!

Wow. In BC we had snow at 1200 feet until June! And this is a coastal region which is normally warm. Needless to say we had plenty of Guiness to keep us smiling. Thank you for that!