Most skeptics have been clubbed over the head with the “settled science” refrain at one time or another. How can you, a layman, think you are right when every scientist says the opposite? And if it is not settled science, how do folks get away unchallenged saying so?
I am often confronted with these questions, so I thought I would print my typical answer. I wrote this in the comments section of a post at the Thin Green Line. Most of the post is a typical ad hominem attack on skeptics, but it includes the usual:
The contrarian theories raise interesting questions about our total understanding of climate processes, but they do not offer convincing arguments against the conventional model of greenhouse gas emission-induced climate change.
Here is what I wrote in response:
I am sure there are skeptics that have no comprehension of the science that blindly follow the pronouncements of certain groups, just as I am sure there are probably as high a percentage of global warming activists who don’t understand the science but are following the lead of sources they trust. The only thing I will say is that there is a funny dynamic here. Those of us who run more skeptical web sites tend to focus our attention on deconstructing the arguments of Hansen and Schmidt and Romm, who alarmist folks would consider their top spokesmen. Many climate alarmists in turn tend to focus on skeptical buffoons. I mean, I guess its fun to rip a straw man to shreds, but why not match your best against the best of those who disagree with you?
Anyway, I am off my point. There is a reason both sides can talk past each other. There is a reason you can confidently say “well established and can’t be denied” for your theory and be both wrong and right at the same time.
The argument that manmade CO2 emissions will lead to a catastrophe is based on a three step argument.
- CO2 has a first order effect that warms the planet
- The planet is dominated by net positive feedback effects that multiply this first order effect 3 or more times.
- These higher temperatures will lead to and already are causing catastrophic effects.
You are dead right on #1, and skeptics who fight this are truly swimming against the science. The IPCC has an equation that results in a temperature sensitivity of about 1.2C per doubling of CO2 as a first order effect, and I have found little reason to quibble with this. Most science-based skeptics accept this as well, or a number within a few tenths.
The grand weakness of the alarmist case comes in #2. It is the rare long-term stable natural physical process that is dominated by positive feedback, and the evidence that Earth’s climate is dominated by feedbacks so high as to triple (in the IPCC report) or more (e.g. per Joe Romm) the climate sensitivity is weak or in great dispute. To say this point is “settled science” is absurd.
So thus we get to the heart of the dispute. Catastrophists posit enormous temperature increases, deflecting criticism by saying that CO2 as a greenhouse gas is settled. Though half right, they gloss over the fact that 2/3 or more of their projected temperature increase is based on a theory of Earth’s climate being dominated by strong positive feedbacks, a theory that is most certainly not settled, and in fact is probably wrong. Temperature increases over the last 100 years are consistent with neutral to negative, not positive feedback, and the long-term history of temperatures and CO2 are utterly inconsistent with the proposition there is positive feedback or a tipping point hidden around 350ppm CO2.
So stop repeating “settled science” like it was garlic in front of a vampire. Deal with the best arguments of skeptics, not their worst.
I see someone is arguing that skeptics have not posited an alternate theory to explain 20th century temperatures. In fact, a number have. A climate sensitivity to CO2 of 1.2C combined with net negative feedback, a term to account for ENSO and the PDO, plus an acknowledgment that the sun has been in a relatively strong phase in the second half of the 20th century model temperatures fairly well. In fact, these terms are a much cleaner fit than the contortions alarmists have to go through to try to fit a 3C+ sensitivity to a 0.6C historic temperature increase.
Finally, I want to spend a bit of time on #3. I certainly think that skeptics often make fools of themselves. But, because nature abhors a vacuum, alarmists tend to in turn make buffoons of themselves, particularly when predicting the effects on other climate variables of even mild temperature increases. The folks positing ridiculous catastrophes from small temperature increases are just embarrassing themselves.
Even bright people like Obama fall into the trap. Earlier this year he said that global warming was a factor in making the North Dakota floods worse.
Really? He knows this? First, anyone familiar with the prediction and analysis of complex systems would laugh at such certainty vis a vis one variable’s effect on a dynamic system. Further, while most anything is possible, his comment tends to ignore the fact that North Dakota had a colder than normal winter and record snowfalls, which is what caused the flood (record snows = record melts). To say that he knows that global warming contributed to record cold and snow is a pretty heroic assumption.
Yeah, I know, this is why for marketing reasons alarmists have renamed global warming as “climate change.” Look, that works for the ignorant masses, because they can probably be fooled into believing that CO2 causes climate change directly by some undefined mechanism. But we here all know that CO2 only affects climate through the intermediate step of warming. There is no other proven way CO2 can affect climate. So, no warming, no climate change.
Yeah, I know, somehow warming in Australia could have been the butterfly flapping its wings to make North Dakota snowy, but by the same unproven logic I could argue that California droughts are caused by colder than average weather in South America. At the end of the day, there is no way to know if this statement is correct and a lot of good reasons to believe Obama’s statement was wrong. So don’t tell me that only skeptics say boneheaded stuff.
The argument is not that the greenhouse gas effect of CO2 doesn’t exist. The argument is that the climate models built on the rickety foundation of substantial positive feedbacks are overestimating future warming by a factor of 3 or more. The difference matters substantially to public policy. Based on neutral to negative feedback, warming over the next century will be 1-1.5C. According to Joe Romm, it will be as much as 8C (15F). There is a pretty big difference in the magnitude of the effort justified by one degree vs. eight.
Jessica,
When you look at reconstructions of paleo temperatures or gas concentrations, you should always try to get graphs that have error bars in addition to the nice smooth curves usually presented. Error bars show the amount of confidence that a set of data provide. By looking at the error bars, you can see how precise the presented charts are. You can do some reading about error bars at http://en.wikipedia.org/wiki/Error_bar
Why would anyone come here to learn about the climate? It’s run by an idiot, and mostly populated by ignorant idiots who don’t ever seem to have taken the trouble to think before typing. I strongly doubt that ‘Jessica’ is actually a high school student. If she is, I hope she fails her course, as she clearly has no idea how to use resources such as text books. It’s a terrible, terrible idea to read the random thoughts of an idiot on the internet, instead of a text book.
JNicklin: “Today, we use one site, Mona [sic] Kea, for measuring CO2″
No. CO2 is measured all over the world. This is a ridiculous error to make! That you would not think to question this bizarre assumption tells us all we need to know about your scientific ability.
Jenn,
Even those who agree with your religious faith in AGW cringe. Take the hint.
And your advice about who to not believe on the internet is certainly one people apply to you within a few second’s worth of reading your spew.
Have you figured out yet, btw, if we are in an ice age or not?
And wishing failure on someone- even someone maybe posing as a student- is low, even for you. Or maybe not.
Hunter
I am not going to attempt to argue with you. It would be a complete waste of my time, seeing as how there would be no way to prove myself. I appreciate your vote of confidence. Anyways, the textbooks we use are outdated.
JNicklin
Thanks again for your help. I just needed some help in understanding those topics, so I could have better luck in researching it.
Jessica –
You are actually witnessing a significant behavior of scientists. I’m not saying Hunter/Jennifer are scientists, I don’t know them. But I do know real scientists.
Some among the non-scientist public believe scientists are quiet, thoughtful, polite, generally agreeable,agree on the facts,and always right. Nothing could be further from the truth. Given a phenomenon, ph. A we will call it, different scientists in the relevant field can and do frequently disagree on what ph. A is, what causes it, or other particulars. They sometimes with great passion defend their hypothesis and ridicule scientists who don’t agree with them. In short, scientists are human beings subject to all the foibles of Homo sapiens. Scientists have made up data and submitted as fact. It has been published by reputable scientific journals. Scientists have to eat and feed their families. Much of their money comes from Federal grants. Without that grant money, there would be far fewer scientists as the execution of science frequently takes a lot of money and special, costy equipment. Global warming has and continues to be a cornucopia of money for scientists. This motivates them to keep the alarm alive. Other scientists, just as other people, have a political point of view. Some of these believe humans are destroying the Earth and are actually anti-human. They see global warming as a way to get governments to force people to live a less opulent life, thereby utilizing less of the Earth’s resources. You should always consider the source when you are looking for facts is my point here.
Hunter……..yawn……..
Hi all
I don’t know how many “Hunters” there are here but I have to say that low climate sensitivity (much beloved by sceptics) is incompatible with what we know about ice ages. I would also like to say that this post is the most reasonable I’ve seen from here for a long time. There are people who hold silly views on both sides (“there is no warming” etc. versus “sea level will rise 25m this century”) but the sceptics tend to have more than their fair share. Most of the pro-AGW “alarmists” have failed to see the clarfications and caveats that scientists routinely place upon the science.
Many (most?) of the sceptics have failed to distinguish between their political views (which in my experience tends towards libertarian and right wing) and the fact that climate change is real. They have fallen into the trap of thinking that because the policy implications of climate change might well include green taxes, restrictions on growth, travel etc, which they hate on ideological grounds, it means that AGW can’t be happening. Clearly this is illogical.
Finally, there is a very good reason why we talk about ‘climate change’ rather than ‘global warming’….many of the effects we see are the result of seconday processes (ie changes in ocean and atmospheric currents, ice sheet stability etc). I’m sure you knew that!
san quintin,
We are in an ice age, and have been for a very long time.
We are in an interglacial period.
‘Climate change’ nor climate science are driving policy. Skeptics that I am aware of, and I know a few, do not dispute that CO2 is a GHG or that it has increased. But AGW – the (false) assertion that human introduced CO2 is leading to an apocalyptic change in the climate system, is driving policy. That is what skeptics are pointing out: That AGW is a fear driven and fear profiting scam.
That you have to talk climate change, when for decades, right up until the warming of years ago ended, all that was spoken of global WARMING.
You don’t get to dissemble away from the complete and utter failure of AGW predictions by simply changing the name.
And the policy ‘solutions’ for AGW are garbage because they are garbage, not becasue they are left or right. They are simply wrong. Like many government programs, they are the wrong solution for a non-existant problem.
No matter how slick the packaging.
Hi hunter (the real one)
That’s a lot of mistakes for one post! We are not in an ice age…we are in the Holocene interglacial. There are lots of sceptics who argue all sorts of stupid things….including that there is no warming, that CO2 is not a GHG, that glaciers are all advancing etc. No scientist is claiming that ‘apocalyptic change’ (whatever that may be) is happening now…just that there is a very high likelihood of it.
You also clearly don’t know the difference between weather and climate. I suggest you look it up. You think the AGW are garbage and so are the policy solutions. Show me how, and then show me what your solutions would be. Do nothing? I tried to be civil…maybe you should try it too.
Another thing…show me how low sensitivity explains the pattern of glacial/interglacial transitions.
san quintin,
The political aspect interests me. It does seem to be true that most skeptics are libertarian or right-wing. However, it also seems to me that most “alarmists” are left-wing. This leads many to think that skeptics somehow “know” that AGW is real and a dangerous threat, yet, because it would conflict with their politics, they choose to ignore it. That’s absurd. I’m a libertarian and if I was convinced that AGW was a great danger and that the only way to avoid it’s consequences was to institute a “world government”, I’d be all for it. The idea that I’d endanger my children and grandchildren’s lives rather than give up my free market beliefs is close to insulting (not that you’ve suggested this, but other have).
There’s a far more innocent reason that the two wings end up on opposing sides of the AGW debate. Everyone approaches new issues from their particular world view. The right tends to be skeptical of experts, believe that more government is rarely the answer and that things will be fine if left alone. The left tends to believe experts (since they have litt;e faith in cultural knowledge), believe that government is required to solve most problems and think that the masses can’t make it on thier own without the guidance of their betters. Given these starting points and the fact that very few people are capable of letting the facts disuade them, it’s not surprising that right = skeptic & left = alarmist is the the outcome.
However, good science is good science regardless of one’s political stance. One’s political loyalties are of no consequence to the quality of the science. While politics can inform an understanding of the motivations behind the opposing viewpoints, when discussing scientific issues, referencing politics is essentially just an ad hom attack.
As for the “climate sensitivity” issue, I think this site has done the best job I’ve seen in support of a low sensitivity based on objective historical data. Do you have a counter argument for that?
san quentin,
Check your facts about whether or not we are in an iceage:
http://en.wikipedia.org/wiki/Ice_age
You would be wrong.
As to apocalyptic change not being threatened by reputable scientists:
http://www.globalwarminghysteria.com/blog/james-hansen-outgores-gore-on-gw-apocalypse-timing.html
As to weather vs. climate, weather is not climate, but climate is composed of weather.
If the weather isn’t doing anything unusual- and it is not- then neither is the climate.
As to what to do, I suggest we do what we were working on doing before the AGW hypesters highjacked the public square:
Work on cleaning up the environment, being more energy efficient, and dealing with Earth’s ever changing cliamte system.
BillB – I agree with you. One should focus on the science and leave the personal motivations out of it. Scientists on both sides of the issue should abide by that rule. Unfortunately, some of them, being human, don’t. But OTOH, I think one would be negligent not to acknowledge that fact. Science is a human endeavor. Scientists sometimes are not honest and are sometimes subconsciously influenced by their own non-science beliefs, political agenda, and/or material needs. People pretty much expect this behavior from politicians, but often don’t see scientists in the same light. It is the methods of science including replication, skepticism, and scrutiny that eventually winnow out the bad science from the good. I think in ten years or so, the majority of people will see that some of these non-science factors were at play WRT global warming. Time will tell.
There ARE some positive feedbacks; for one the emissivity of seawater goes down a little in stormier, rougher seas, up a little in warmer, calmer seas. The albedo of earth increases with the growth of glaciers, decreases with shrinking glaciers.
The polar ice caps currently constitute 1.5% or so of surface exposed to the sun. Likewise, the emissivity of the oceans is already 0.95%, so there’s not much room for more positive feedbacks to further warming.
There’s PLENTY of room for positive feedbacks in global cooling- growing ice and snow leading to increased albedo, colder and rougher oceans leading to lower emissivity and further cooling.
Pardon my typo, it should have read “the emissivity of the oceans is 95%” = 0.95, not .95%
san quentin,
Perhaps you should check out your positions a little more closely.
We are in an Ice Age:
http://en.wikipedia.org/wiki/Ice_age
As to reputable scientist and declarations fo apocalypse, most AGW believers think Hansen is reputable. Do you?
http://www.globalwarminghysteria.com/blog/james-hansen-outgores-gore-on-gw-apocalypse-timing.html
or
http://www.huffingtonpost.com/dr-james-hansen/twenty-years-later-tippin_b_108766.html
or is Lovelock not reputable?
http://www.guardian.co.uk/theguardian/2008/mar/01/scienceofclimatechange.climatechange
and here is a nice AGW promotion blog that is certain *the* end is near:
http://westcoastclimateequity.org/?p=440
As to feedbacks, that we have not ever done as Hansen prophesizes- gone ren away in billions of years- it shows that the positive feedbacks are limited in scope, and ultimately overwhelmed by negative feedbacks. I think a term like ‘dynamic stability’ where positive and negative feedbacks largely offset each other would be a more productive way to look at our climate.
I find the magnitude of the postulated temperature rises of AGW impossible to accept.
Consider the heat balance at the Earth’s surface. After albedo is taken into consideration, on average there is an input of 240 Watts/meter-squared short-wave solar radiation, and a long wave emission of 40-60 (say 50) Watts. This leaves a balance of 190 Watts lost due to evaporation and convection, forced by an increase in the earths temperature by 33K from 255K with only albedo considered to 288K. These figures are commonly accepted by most skeptics and proponents of AGW.
The AGW argument hinges on how much the surface temperature will rise given an increment in heat at the surface. This concept is easily inverted by considering the incremental heat flows in response to an increment in temperature. The long wave radiation increment is most easily calculated by assuming a constant radiative emissivity (0.128, *5.67e-8*288**4 = 50W), comes to about 0.7 Watts/degK by differentiating the Stefan-Boltzmann equation. I would assume this is uncontroversial. ( dQ/dT = 4 * 0.128 * 5.67e-8 * 288**3)
However AGW disaster scenarios are built on feedbacks of 3 degK/Watt and more, or less than 0.33 Watts/degK. For this to occur, the evaporative/convective incremental power loss would have to be negative. However if the earth had the same albedo but no atmosphere, the evaporative-convective loss would be zero, and the temperature would be 255K. As atmosphere is added, the temperature would gradually rise, and the evaporative-convective power loss would also rise.reaching 190 watts at 288K. What is unknown is how the power loss varies with surface temperature at 288K. A straight line fit would give 5.75 watts/degC. If this were the feedback, combining with the long wave feedback, would give an overall feedback of 0.15 degC/Watt.
To obtain the disaster scenario feedback, the incremental convective power loss would have to be negative at -0.3 Watts/degK to compensate. This is highly unlikely, and requires extraordinary verification to be plausible, and that verification has not been forthcoming. It would require some sort of physical mechanism explaining why the evaporative-convective power loss not only saturates with increasing GHG concentrations, but decreases.
Hi BillBodell.
Thanks for your reply….I guess that the point I was making is that many of the right wing don’t want AGW to happen (for ideological reasons perhaps) and are therefore incapable of accepting the science. This seems to me to be illogical. Similar ideologically-driven people were against the notion that smoking caused cancer, and that CFCs affected the ozone hole. It seemed to me that both of these showed the importance of regulation and the limits of the free market (both of these views are denied by the right and libertarians). As a result, there was a sustained attack on these by the free-market right, despite the science. A similar process is happening with climate change. I’m not assuming that you are like this. Neither am I….I’m a scientist heavily involved in climate research (and accept the science showing AGW) but am also not left wing. As for high climate sensitivity…well if the sceptics want a global MWP or LIA then this is incompatible with low sensitivity. Similarly, our understanding of the LGM forcings and the global temperature response requires a high (3C or so) sensitivity.
san quintin – if you are a scientist, you are not very objective. You make assumptions and assertions about others and you have not proof. You paint conservatives with a broad brush and this is typical of liberals (I did not you claim not to be “left wing”). I am a Republican and conservative, yet I believe that markets need regulation, that the homeless should not be relegated to living on the streets, and further more that an Ayn Rand style free market system is an insane proposition. I really don’t get people like you who make careless assumptions about others – it reminds me of racism.
san quintin – Why do you think the Sun isn’t responsible for the temperature variations implied by the various proxies? Even if it is difficult to assign absolute temperature via the proxies, obviously there has been variation. Are you using temperature reconstructions as proof the Sun is not the cause of the temperature variations? If not, what or what else?
san quentin,
Maybe I am not as wrong as you wish:
http://en.wikipedia.org/wiki/Ice_age
“Glaciologically, ice age implies the presence of extensive ice sheets in the northern and southern hemispheres;[1] by this definition we are still in an ice age (because the Greenland and Antarctic ice sheets still exist).[2]”
I would say that skeptics can be wrong, but they are not the leaders of the skeptics. Here is what leaders of AGW have to say:
Hansen-
http://www.globalwarminghysteria.com/blog/james-hansen-outgores-gore-on-gw-apocalypse-timing.html
“With just 10 more years of “business as usual” emissions from the burning of coal, oil and gas, says the NASA/Columbia paper, “it becomes impractical” to avoid “disastrous effects.”
The study appears in the journal Atmospheric Chemistry and Physics. Its lead author is James Hansen, director of NASA’s Goddard Institute for Space Studies in New York.
The forecast effects include “increasingly rapid sea-level rise, increased frequency of droughts and floods, and increased stress on wildlife and plants due to rapidly shifting climate zones,” according to the NASA announcement.”
http://www.youtube.com/watch?v=auTEWanRTfM
And of course there is more. Much more.
In reply to san quentin: Many of the left wing are incapable of understanding the economics of the adjustments proposed by AGWers. We’d have to cut back emissions 80% for the world as a whole to meet the AGW goals. For the US, since we consume roughly 4 times the average energy, it would be more like 95%. The only countries in the world below those levels now are Haiti and Somali. The only way anyone would voluntarily reduce their economic consumption to those levels would be at the point of a gun.
In reply to san quentin: Many of the left wing are incapable of understanding the economics of the adjustments proposed by AGWers. We’d have to cut back emissions 80% for the world as a whole to meet the AGW goals. For the US, since we consume roughly 4 times the average energy, it would be more like 95%. The only countries in the world below those levels now are Haiti and Somali. The only way anyone would reduce their economic consumption to those levels would be at the point of a gun.
Jeff got to this first, i ask too this same thing.
You say “The IPCC has an equation that results in a temperature sensitivity of about 1.2C per doubling of CO2 as a first order effect”
I agree that this is true. However, we shouldn’t discount the possibility that the feedback may be negative — of course it would result in a lesser increase rather than a decrease.
The reason I say that is simply because as you know the numbers are NOT well established and while negative feedback is generally considered impossible by the consensus, I’ve seen no proof or even good evidence one way or the other yet.
I know you don’t often answer to comments in your blog but I’ll try anyway, what are your thoughts on this?
April 29, 2009, 8:28 pm
san quentin,
We are in an ice age, for starters. Look it up. I am unable to make posts with links in them at this site, apparently. Wiki, while pedestrian, is well documented on this topic.
While extremists on both sides of the AGW question may say silly things, for the AGW belief side, the set of ‘extremists who say silly things’ and the set of ‘AGW opinion leaders’ are nearly the same.
Hansen, Gore, Lovelock, Mann, etc. all say things that are factually wrong, designed to create massive fear on false statements, etc.
In other words, the extremists of AGW are leading it.
Hi Hunter
The point I was originally making is that you can’t explain glacial/interglacial transitions without a reasonably high sensitivity…something that the sceptics deny. The point about Hansen, Lovelock, mann etc (Gore isn’t a scientist) is that they aren’t alarmist. They all say that there is a fair chance that climate change will be rapid and serious if we continue to emit Co2. Hansen is right…the whole point about the palaeo record is that sea level rise can be very rapid and that 3C may well cause 20-30m sea level rise as it has in the past. This seems pretty alarming (if not alarmist!).
san quinten – Well, I see you dodged my question to you about the Sun causing the temperature variations. So much for you discussing science. Even if the alarmist are correct, warming will have some negative consequences and many positive ones as well. It will be easier to grow crops and while more people will die of heat stress, all in all warming is better than severe cooling. If the glaciers return, most of us will die. So even if you happen to be right, you are wrong about the alarm part.
Hi Jim. The reason I didn’t answer your question about the sun is that I didn’t think you were serious. We can reconstruct past solar variation (using 14C, berillyum etc) and they aren’t sufficient to drive climate on their own. Do you have better information? The majority of solar physicists say that present warming is not caused by the sun. Sorry about that.
As I’ve said before…if you want to overturn AGW you will have to produce an alternative, testable theory with as much explanatory power as AGW, and one which also explains why CO2 somehow isn’t a GHG. The sceptics have had decades to produce one….and they’ve failed. All you seem to do is to shout “it’s the sun” without producing any science to back it up. Do you now see why scientists don’t take sceptics seriously?
san quintin – Thank you for your answer concerning the Sun. I am always up for learning more about this. I have to ask you again. You mentioned that the solar output can be measured by C14, berillyum, etc. Are you (and the solar physicist majority) comparing that data with temperature reconstructions in order to obtain your conclusion??
It is funny you mentioned “testable theory.” I was just thinking today, that before quantum mechanics turned the world of physics on its head, science was conducted via hypothesis that could be tested by a controlled experiment. This sort of science still is generally, but not always, accessible in chemistry. Certainly a controlled experiment isn’t possible with the Earth; 1) because we don’t have two of them and 2) even if we did have two, we don’t have the means to manipulate them. So I assume that for you, testability refers to computer models?? Is that correct or do you use some other test?
Hi Jim. I agree with you about quantum mechanics….and wouldn’t for a moment suggest that we know everything about AGW or science generally. But there were real issues in physics before Planck including ralleigh-jeans Law that gave a hint that there were things missing in classical physics. I also agree about the impossibility of controlled experiments with the earth, and I don’t accept that GCMs are the last word on this either (in fact, over the past couple of years I’ve published several papers pointing out the problems with GCM projections). Still, we can use the palaeo record to show that T and GHG are tightly correlated and that the sun only plays part of the role in driving climate.
Now we have the highest level of CO2 for 700 ka (or 25Ma?) and we have a sustained trend of high and rising T. We know that GHG MUST warm the atmosphere (basic radiative physics going back to Fourier). We also know that the radiative effect of changes in TSI are positive, but much too small to account for the T increase. Even if the sun were responsible, we would then have to explain why this enormous increase in GHG wasn’t having a T effect!
Re: hunter. I accept your point re ice ages….what I assumed you had mean was that we were still in a glacial. Sorry.
san quintin – I’m not so certain the reconstructions of either CO2 or temperature are completely reliable, especially when attempts are made to translate the various proxies to absolute levels or tack on modern instrumental readings to the proxies. However, I do feel more confident in the, shall we say, first derivative of those proxies. It would appear that temperature changes precede similar channges in carbon dioxide concentration in the ice core data. Since the two measurements are taken from the same sample, it is difficult to see how one could argue cause and effect, i.e. CO2 increase will cause temperature increases. Do you dispute this interpretation of the ice core data?
WRT to the GHG concentration increase, even the AWG proponents are not saying the bulk of warming is caused by CO2. They say it is the response of water vapor to the increase in CO2 concentration that is problematic. Correct?
san quentin,
The point is you are wrong. We are in an ice age.
If we were in a highly sensitive, positive feedback dominated world, we would not be in an ice age. We would be Venus.
And if you think Hansen and pals are not alarmist, I think we will just have to agree to disagree.
san quentin,
After reading your post to Jim, I thank you again for being reasonable and professional.
My post above was before I read through. I had tried to post, with links, for several days and finally just put up something to at least respond.
The observation I would offer after reading your post to Jim is this:
You are characterizing the changes in global T as large, and the data as reliable.
I think we are seeing many examples of why neither is actually very reliable.
The actual energy inputted, if the laboratory measurements of CO2 are 100% reproduced in nature is not really very much.
And the feedback processes of the atmosphere itself, which are not well measured on the negative side, can easily offset something in the 0.5% range.
Regards,
Does anyone reading this have access to GCM model runs?
I’m curious if there is a higher probability of a ten year pause in temperatures between different models?
Been having this back-and-forth on Chris Colose’s blog(‘Decadal scale coolings no unlikely), and this is a bottleneck.
“If we were in a highly sensitive, positive feedback dominated world, we would not be in an ice age. We would be Venus.”
Non sequitur. Try and think before you type.
Hi Jim and hunter. As with all reconstructions, there are uncertainties in the palaeo record for T and CO2. But they are as good as we have got. Do you have any better idea?
Jim…You are right…during glacial/interglacial transitions the initial warming is via changes in High latitude insolation and GHG play the role of an amplifier of this warming (insolation alone isn’t sufficient to melt a continental-scale ice sheet for instance). Thus there is a lag between initial T rise and CO2. But this shouldn’t be seen as a weakness in AGW theory as it was predicted by scientists long before we had ice core records and there is loads of supporting evidence for this (ocean degassing, melting permafrost, vegetation change etc). I also don’t think it’s controversial to say that doubling CO2 on its own causes more than 1.5 C warming…it’s the feedbacks (water vapour, albedo etc) that then increase the warming. Again, established science. What we have now is human-emitted CO2 with no orbital forcing. The CO2 does what the physics says it must do…and the atmosphere warms.
Just because we have positive feedbacks doesn’t turn is into Venus. CO2-induced warming will trigger feedbacks but these aren’t ‘runaway’ in the sense of Venusian climates.
We’d have to cut back emissions 80% for the world as a whole to meet the AGW goals. For the US, since we consume roughly 4 times the average energy, it would be more like 95%. The only countries in the world below those levels now are Haiti and Somali.”
If you don’t know what the facts are, just make them up, eh, Alan D. McIntyre?
Here is the data. It gives US emissions as 5902 million metric tons of CO2. 5% of that is 295.1 million metric tonnes of CO2. There are in fact only 20 countries which emit more than that. Here is the complete list of countries which emit less than that:
Or perhaps you meant per-capita. The US emits 19.78 tons per capita. 5% of that is 0.989 tons per capita. Here’s another list of all 61 countries that emit less than that:
“The only way anyone would voluntarily reduce their economic consumption to those levels would be at the point of a gun.”
You appear to believe that prosperity arises only through releasing CO2. Apart from that being transparently ridiculous, and apart from your claim about Haiti and Somalia being a product only of your diseased mind, what exactly do you think is going to happen when fossil fuels run out? We all turn into Somalians?
Jennifer,
We are having a civil conversation. If we want that to change, we will be sure and give you a ring.
Otherwise, please continue to lurk. And do please explain how ice ages are examples of positive feedback.
san quentin,
Talk to Hansen about Venus. He is the one that brought it up. I have ridiculed it every time as stupid and irresponsible. Since the great ice melting fear is joining the great hurricane fear in the ‘failed AGW claims’ bin, I suggest you find other things besides a melting Arctic to focus AGW believer’s fears on.
Who ever said ice ages were ‘examples’ of positive feedback? That’s like saying your car’s speed is an example of its accelerator pedal. You demonstrate time and time again that you’re not capable of understanding simple terminology.
When, and in what context, did Hansen bring Venus up?
I’m getting a little confused here about who said what. Changes in albedo, reduction in GHG etc help explain the initiation of glaciations….this would be a positive feedback. I don’t think anyone is seriously considering a runaway warming like Venus. However, high sensitivity (6C or so?) would be catastrophic on its own.
hunter: if you disagree with hansen then do what a scientist would. Publish a paper in the peer-reviewed scientific literature setting out your reasoned arguments showing how he is wrong. This is what all the sceptics should be doing if they disagree with AGW. Blogs are great, but they don’t replace the literature.
san quintin – WRT to the temp reconstruction, much of the dire global warming predictions hang on these. If they are not good enough, in my view we should not rely on them to make decisions of this magnitude – very expensive and onerous changes will result from these decisions.
Could you add some detail on the temp rising before CO2 rise scenario? Are you saying the temperature rises first, the forcings/feedbacks take over? If that is the case, why does temperature go down before CO2 goes down. It seems what with the high CO2 levels, if forcings/feedbacks made the temperature higher than it otherwise would have been, then the temperature would not go back down. What makes it go back down?
Hi Jim. I don’t think that the GW predictions hang on T reconstructions too much. We have multiple lines of evidence to suggest that sensitivity is 3C or thereabouts (including from recent events such as vocanic eruptions, Maunder Minimum etc)…therefore we know that 550ppm will eventually produce 3C rise with likely severe implications for sea level etc.
Your second question: yes, T rises first, then CO2 amplifies this. After a while, orbital forcing produces gradual cooling, with incresed ice sheet extent and permafrost and cooler oceans. These all sequester GHG and increase albedo….so the T falls. There’s loads of detail in journals like Quaternary Science Reviews.
I might not be posting much for a while….I have a day job as well!
Hunter thanks for the list of countries. I’d say you proved his point quite well. What is the lowest percentage of emissions/GDP for developed countries? Is it the Netherlands?
san quentin,
My boss just reminded me of the same thing.
MikeN: I proved he was making things up rather well, yes.
I gave a link to the data. You’d need to define ‘developed’ to answer your question but you can find the emissions per capita per GDP data at the link I gave.
san quintin,
Drat, just when I think I’ve got a reasonable pro-AGW to talk with, he’s got to go back to work.
I proposed that everyone approaches new issues from their particular world-view (liberal, conservative, libertarian, etc.) and that this colors their initial response. Most people seem incapable o altering their initial opinions in the face of well reasoned arguments. There is a point, however, at which even the most reluctant will come over to the “correct” side (we’re not there yet regarding AGW). I don’t see how this makes AGW skeptics unusually “anti-science”. Liberals have the same problems when the science goes against them. I did an experiment over at Deltoid regarding Economics and Minimum Wage laws. Liberals and Conservatives promptly switched sides; with conservatives referring to the “consensus” and quoting peer-reviewed literature and liberals denying that there was a consensus and quoting papers outside the mainstream. There was even an article by an Economics professor that talked about how much trouble he had publishing against the consensus and how he was made to feel like an outcast by his academic peers.
Just to define our terms: most every skeptic I’ve read agrees that CO2 is a greenhouse gas, that the Greenhouse theory is correct and that humans have, no doubt, contributed to Global Warming. The debate is over the magnitude of the effect. There really needs to be a better term CAGW (Catastrophic AGW)?
I’m not sure what your point regarding smoking and CFCs was. I’m not sure what free markets and regulation have to do with smoking. I haven’t spent much time with the CFC issue, but once enough people were convinced that CFCs were having a negative effect, this is an “external cost” and market based solutions were available and regulation is certainly a valid option. Certainly skeptics have been proven right on several issues such as alar, breast implants and “crack babies”. I suspect that if you kept score, skeptics have made the right call more than their fair share of the time.
As to “Climate Sensitivity”, we are talking about the standard definition of climate sensitivity as the effect on global temperature caused by a doubling of CO2 right? I’m not sure how this relates to the MWP or LIA. Are you saying that the ONLY way that climate changes is due to CO2? And that since there were, at most, small changes to CO2 during these times that there must be a high climate sensitivity? I don’t think that skeptics believe that the MWP and LIA were caused by changes in CO2 concentration. I would think that there are other processes that effect climate than CO2 and that they might be responsible for these events.
We are about 43% of the way to a doubling of CO2 from 270 ppm to 540 ppm. At this point, we should have seen approximately half of the warming caused by the increase in CO2. Yet, the temperature has only increased by about 0.6 C. Even attributing ALL of the warming to CO2 (ignoring the distinct possibility that a significant amount of the increase in due to uncorrected UH1 effects), that gives a climate sensitivity of approx. 1.2 C. All I’ve heard in response is “aerosols” or “the heat is in the pipeline”. It seems straight-forward, we have seen an increase in CO2, we have a temperature record, where’s the evidence of a 3 to 5 C climate sensitivity?
You mentioned that. in order to displace AGW, skeptics need to come up with a better theory than AGW. Skeptics are not necessarily interested in knowing what the best theory is. As far as I’m concerned, AGW may well be the leader in the clubhouse. The issue isn’t “what theory is best”, it’s “are we certain enough of CAGW that it is worth suffering the known consequences of drastically reducing CO2”. This is the point of the debate, not “who’s got the best theory”.
Hi Bill: I’ve now got a few spare minutes. Yes, you are right about the ‘world view’ that people from different political persuasions have. I have political views just like everyone else, but the point of being a scientist is to be as objective as we can be when doing our science. I spent a very long time being sceptical of AGW (as all scientists should be) until I was convinced by the overwhelming science from half a dozen different disciplines. If AGW were based just on (say) palaeoclimatology, then it would be on much dodgier ground. But when you have glaciologists, chemists, physicists, climatologists etc all essentially saying the same thing (that CO2 is a GHG and that the climate and associated systems are sensitive to atmospheric CO2) the onus really is on the sceptics to put forward an equally persuasive alternative theory. They haven’t done this.
I certainly don’t argue that the LIA and MWP were driven by CO2 (although it MAY have had an impact on the LIA). Clearly climate change can be caused by loads of things….but when we can rule out solar and other influences, and see enormous increases in GHG the attribution is clear.
Your view on why we haven’t seen large warming so far in response to GHG forcing is well put. However, there are clear lags in the climate system…and sensitivity is an equilibrium response not a transient one…it will take time. At the moment we are in early May and it’s cold here. By early August (same solar forcing) it will be much warmer here….there are lags at the seasonal level too. the point about sensitivity is that we can’t have big climate changes in response to relatively modest forcings (LIA, MWP etc) without sensitivity being high. Same goes for LGM. Don’t forget sceptics want both a global LIA and MWP and low sensitivity! I can’t square this circle.
Back to work!
san quintin is incorrect in accepting that it was reasonable for so many scientists to rule out solar and other influences.
The recent warming coincided with a grand solar maximum, a run of powerful El Nino events within a positive (warming) Pacific Decadal Oscillation and a poleward shift in all the main air circulation systems.
All those factors have been going into reverse since 2000 with first a pause in warming and now a cooling.
In view of recent developments the AGW hypothesis is becoming less convincing by the day.
Regarding the list of countries, you might be interested in C02 emissions per GDP. If the US cut its emissions by 80% but kept its same GDP, there is only one country that would have a lower CO2 per GDP — that would be Chad. At the present time, the United States is in the upper half of countries for lowest CO2 per GDP.