Tuesday, December 15, 2009

Thoughts on “Climategate” from a Computational Scientist

If there is a more controversial topic in science than climate change I don’t know what it is. Even then most of the controversy isn’t really about the science - it’s about the politics, economics, and ideology related to the science. I have previously posted on how people’s opinions about climate change are influenced by non-scientific factors. For those of you that follow the news, you have heard a lot about the recent controversy over copies of stolen e-mails from the University of East Anglia, Britain’s main climate research center. These e-mails contain unprofessional comments about climate change skeptics, comments about data analysis “tricks”, and even a couple remarks about denying, delaying, or deleting public data requests. For a good summary of the whole mess, see this story from the New York times.

Dubbed “climategate” by conservatives, many have pointed to these e-mails as evidence that the science behind climate change is false. One writer has gone so far as to say that this is “the final nail in the coffin for global warming”. I am not a climate scientist, but I do work with climate scientists and I do work on large computer simulations of the sun which are somewhat analogous to the global climate models (GCM’s) upon which many future predictions about climate change are based. So here are my thoughts on this whole mess.
  1. Nothing that I have seen in these e-mails suggests that the science behind global warming has been faked. Anybody who has ever taken a math class has learned “tricks” for working problems. Computational science is full of simplified approximations that make these simulations possible. There are a lot of simplified approximations in climate science, but the overall consensus between many different models using many different approximations is that humanity is driving up atmospheric concentrations of CO2, which it turn warms the planet. Currently all of the major computational models agree that observed warming trends are largely due to anthropogenic forcing, so while one model would be questionable, the fact that all of them agree on this point is a pretty good indication that they’ve got it right.
  2. Most people have no idea how science is done. Science classes are filled with tidy little experiments that produce tidy little results that are always consistent with other experiments and never unexpected. Real science is full of ambiguous individual results that on their own lead to uncertain conclusions. But when real scientists see strong statistical trends in data over many different models and experiments, they can confidently draw correct conclusions. The general public (and many with political agendas) are often uncomfortable with the idea that unresolved details can be a part of a well-supported theory, so they either discard the unresolved details or the well-supported theory.
  3. Like many people, some scientists have big egos and lack social skills. On top of that, scientists have spent years learning the intricacies of their specific research topic. Add to that the fact that a large portion of the general public - including many politicians - are essentially scientifically illiterate and some scientists can at times feel justified in draconian measures like repressing dissension or limiting access to data to get the general public to agree with scientific facts. It’s not right, but at the same time I think think it comes more from frustration than some sort of politically motivated conspiracy.
  4. One thing that no one in science will stand for is bad science. If climate change could be disproved through rigorous scientific tests it would be the sort of result that would make the person that accomplished it an instant celebrity in the climate community. To borrow an example from astronomy, in the late 1990’s two independent teams of highly qualified astronomers released independent data showing that the expansion of the universe was accelerating. This destroyed 40 years of work in cosmology that assumed a decelerating universe - in some cases entire careers’ worth of work was rendered invalid overnight. There were a lot of skeptics, but the data was solid and the two teams measurements were independent. When the results were announced at a meeting of the American Astronomical Society they were met with a standing ovation. The point is the scientists as a whole are interested in the truth even if its not on their side of the argument. If there were conclusive evidence showing the global climate was not changing climatologists would embrace it. The reason most of them fight skeptics as hard as they do is that the data disproving climate change simply isn’t there. Instead all sorts of tests indicate that the climate is changing due to human activity.
So there are my thoughts. The e-mails don't disprove the science behind climate change, but they do lay bare some of the short-comings of both the general public and the scientific community.


  1. Great post Nick. I think it comes down to:

    1. Scientists are not politicians writing emails using well thought out language so sometimes their private emails can easily be made to look like a conspiracy is at play.

    2. Regardless of what happened, there are a lot more scientists at many other institutions who have data supporting global warming.

    I think the real debate needs to be:

    "Given global warming is real, what should be the government's role be in dealing with it."

  2. I did study environment in Germany during a year and I know that in order to make progress their science they are putting some motivations leading to excess, because of money for example. Otherwise it is strange that more we do worth is the situation and more is asked to us, more money and free contributions, I think it is going a bit too far currently.

  3. Great post! I must confess, I have been a skeptic of Anthropogenic Global Warming. Not because I'm unscientific (I'm an engineer afterall, working at a National Lab) but because I have questioned the politics in science. In that vein, let me sincerely ask:

    Is there any truth to the argument that scientists will follow the money? Ideally, yes, science is interested in the truth. But the reality is that scientists rely on gov't grants, and other federal/commercial monies to do their work. Certainly scientists will shift gears, at least in small increments, to follow the money? I have seen this in my field. This doesn't make the science invalid, but it might mean that there's some serious confirmation bias, and/or cognitive dissonance at play here. Furthermore, I do not believe that it is impossible for an entire group of experts to be duped. Look at Keynesian economics, or the spaceshuttle challenger accident for good examples. Proving causation (not just correlation) is a rather difficult task, and I'm skeptical that we are there. But alas, I'm not climatologist, or even a computation scientist working on modelling the sun, so I admit ignorance.

    In any case, Joe has it right, the real question is what should government's role be in dealing with it.

  4. jmb275,

    The areas that scientists research are definitely influenced by funding sources, so I would agree that money impacts the questions being asked, but I have never seen money change the answers to those questions. And on that note, some of the largest sources of funding in climate science have come from the oil, gas, and coal industries. If there were good data to be had to show that the current understanding were seriously flawed, it would have been found already. The biggest issue currently is exactly how much of an effect humanity will have in the future. A lot of the feedback mechanisms to increased forcing are poorly understood, so there is of course a need for more research. That being said, I think that Joe is exactly right. The question really isn't "is humanity changing the climate?" The question is "what needs to be done to deal with it and what is the role of government?"

  5. Hi guys. Haven't been able to post or respond much lately, things have been busy.

    I was thinking of posting on this topic but it seems that Nick beat me to it. When I first read the emails my thought was, "These sound like standard emails between researchers." I find it extremely hilarious to listen to news commentators gripe about the "tricks" that scientists are using to prove climate change. (on a slightly related note, Did you know that in Congress they kill things? Congressmen must be nothing but a bunch of murderers. I hear they kill Bills all the time in Congress...I think I made my point.) As Nick pointed out I don't think that there is anything in the emails to justify the accusation of a conspiracy.

    One thing the emails do show, and I think it is a difficult and delicate issue that needs to be addressed is the peer review process for climate science. One thing that came up in the emails was a move by these researchers to get rid of an editor that was giving them some grief. As someone who takes part in the scientific process I can think of several reasons why their actions were justified. But I can also think of several reasons why it would be a very, very bad idea. One of the most dangerous outcomes would be a redefining of the peer review process to the point that "peer review" and "accredited" means "everything that agrees with me and my theory". If the peer review process is compromised so that the authors of the papers also determine what gets published, that defeats the whole concept of anonymous peer review. And if we don't have anonymous peer review then we have just lost single best method we have of preventing major (and minor) errors in science.

    In terms of the actual science involved, I think that one of the biggest unresolved issues is how climate change will affect us and also the ecosystem. Most of the predictions that make their way into the press are extremely negative (I mean, how many reporters would want to report on a paper entitled "Simple connectivity measures in spatial ecology" as opposed to "Habitat loss and population decline"). The overwhelming negativity in the press creates the wrong impression and also creates a false sense of crisis. Recently I read a short paper that appeared in Science that I found very interesting (I would recomend reading it, in case the link does not work, the citation is: Science 6 November 2009: Vol. 326. no. 5954, pp. 806 - 807). It seems that a few researchers went back and used the exact same computer models used by the IPCC in determining the effect on biodiversity and changed either the number of grid points or in one case one parameter (the effect of increased CO2 on biomass) and in each case they got drastically different results (as in the exact opposite results than the ones used by the IPCC). Now if these models are that sensitive to such small changes, it makes no sense (and is I would say extremely dishonest) to advise governments to take drastic action based on this type of science.

    [continued in next comment]

  6. So in answer to the question, "what needs to be done to deal with it and what is the role of government?" I would say that we (meaning scientists) do not know enough to even begin to tell politicians what to do. In order to be in a position to advise government on taking action scientists must first be sure that they are correct to a reasonable degree (I do not think they are not there yet, but they are getting close). They must also be sure that climate change will actually produce negative results (we may actually figure out that we like global warming, see "Minnesotans for Global Warming"). Then they must show that something can actually be done about it. Of those three things they have only done about half of the first one.

    I think it would make their case better (and more convincing) if they had better models and were more sure of their predictions, and also had enough time to look into and consider all the objections and answer them properly, then they probably would have avoided all the problems they are facing now with trying to convince people (politicians) to act.

  7. Okay, thanks for the response. So Quantumleap42 is confirming what I said about not having shown causation yet (to a reasonable degree), but only correlation. So, the issue is not so much about the money, or whether or not GW is happening, but about anthropogenic causes.

    My position as far as legislation is that the science isn't strong enough yet to pass legislation based upon it. My preferred solution, overall, to the AGW problem is to enforce property rights more strictly. If a company moves next door to you and starts emitting crazy amounts of pollution, you should take him to court for damages.

  8. Quantumleap42,

    "I would say that we (meaning scientists) do not know enough to even begin to tell politicians what to do."

    I think there are a couple of basic things that climate science does know well enough to advise politicians on, although I think that detailed predictions are far beyond our current capability.

    First, I think it is safe to say that we need to move away from CO2-emitting energy sources for environmental as well as political and economic reasons. Perhaps the best way to do this would be to continue to promote renewable energy research.

    Second, we need to reduce emission of CO2. In a cost-benefit analysis even when you factor in the uncertainty in climate change predictions, it will save us a lot of money in the long run to spend a little bit today to limit greenhouse gas emissions.

    Third, we need to accelerate research on these topics so that we'll have better answers soon enough to make small changes so that big changes don't become necessary.

  9. jmb275,

    Correct me if I'm wrong, but the question isn't if people are causing climate change (we are), but to what degree will our activities change the climate. Predictions about the Earth's future climate consistently show warmer temperatures, but what that means for plant growth rates, rainfall patterns, cloud cover, and some other important climate effects has not been settled. Basically, we know two things: it will get warmer on average and things will be different than they are now.

  10. I should add that there are a few effects from warming that are well-understood, such as sea-level rise, increased glacial melt rates, and ocean acidification, but the ability to predict many other features of the future climate range from slightly iffy to very questionable.

  11. A friend pointed to this discussion. You bring some good points.

    There are a few things that are not clear to me. I'll bring them up hoping that someone can enlighten me. I am not convinced by either side (human causes AGW vs they don't). I certainly want a less polluted planet, and I also don't want to depend on the middle east for our oil. But my questions are specifically about AGW.

    To what degree is human CO2 causing increase in temperature?

    I have read that the amount of CO2 that we produce is extremely small compared to the amount produced through natural causes (oceans and volcanoes).

    I have also read that increase in temperature causes the oceans to release large amounts of CO2, so that there is a correlation between CO2 levels and temperature. But it is temperature that raises CO2 levels (not the other way around).

    And I have read that the earth goes through temperature cycles. How do we "know" that the increase in temperature is not part of the cycle?

  12. armk,

    You are exactly right when you say that humanity's output of CO2 is dwarfed by many naturally occurring sources. If you envision a balance between natural sources of CO2 and natural sinks of CO2 (like growing trees, etc), there prior to 1800 where was a rough balance. The problem is that humanity is adding a small but ever-growing source of CO2 are at the same time is removing some of the biggest natural sinks of CO2 by clearing forests and the like. Essentially we are disrupting the balance, causing CO2 to build up in the atmosphere. This amplifies the greenhouse effect and leads to a warmer planet.

    Now there are a number of natural cycles that also warm the planet. In fact we are still coming out of the last ice age and currently the earth is a little cooler than it was prior to that ice age. These cycles, however, act very slowly. Over the past 50 years we have observed global concentrations of CO2 and global temperatures rise far faster than any natural mechanism can act. That's not to say that the observed warming is entirely caused by human activity, but humanity is certainly an important player and probably the leading cause of warming since 1950.

  13. (Continued)

    Basically, scientists don't have all the effects of global warming sorted out yet, but a few things are clear:

    1) We are changing the climate of our planet.
    2) The largest negative effects of those changes are likely to have strong impacts on coastal areas and in the tropics (where poor, developing countries are predominantly located).
    3) We don't yet understand all of the secondary effects of increased CO2 in the atmosphere. Some of these feedbacks are likely to amplify the warming trend while others are likely to suppress it. Some of those secondary effects may be beneficial in some parts of the globe, but the real problem is that rapid environmental change is a destabilizing force.
    4) Even with uncertainties in future predictions, we would be wise to spend a little now to reduce emissions to prevent larger, more expensive problems later.

  14. Having said all that, I'm still going to drive my car home from work tonight. Global climate change is an issue to be dealt with, but it will not be the end of human civilization. Humanity is very good at adapting to the problems we face. However if we can spend a little bit today to save our grandchildren a lot, I say we do it.

  15. I agree that this is mostly a misunderstanding of how science works being exploited for ideological purposes.

    I agree with the importance of peer review. On the other hand, editors have a lot of power in deciding what gets published--or even what gets the opportunity for peer review. I can't get that worked up about boycotting a journal if it really did have a rouge editor. Unfortunately it is difficult for a lay person to judge whether such a reaction is justified due to the technical nature of the subject. But in the case of the Soon paper, the fact that several of the editors--including the editor in chief--resigned, says something, I think.

  16. For armk's benefit, the IPCC reports can be found here. The Physical Science section even has an FAQ document.

    Recently, a number of climate scientists, some of whom were IPCC authors, released an update called the Copenhagen Diagnosis. It is relatively non-technical and throughout the document there boxed sections that deal with common questions.

    These are definitely worth reading through if you want to understand the mainstream view.

  17. Jared*,

    Thanks for the links. The IPCC does a good job, for the most part, keeping with what I would call the really solid results of climate science. They avoid some of the more uncertain and dramatic predictions that tend to catch more media attention.

  18. What is strange is the amount of efforts done and the fact that anyway the resources of petrol are very limited, but the taxes about environment appear more and more and increase. But there should be a minimal impact of the human activity, nonetheless the green organization did begin with some homosexuals (still present) and some bad persons (still present), what could be a great problem in the future ; especially because it is important not to be too much dependant of some countries for petrol (the Muslim ones for example), but I think this argument could be enough in order to change some behaviors. Finally it is freezing in France currently, so global warming is not something in the facts for me currently, but I do not want to be too much negative.

  19. P.-S. : Industries are quite happy with taxes because it helps them to go where workers are cheaper, because they have a good apology in order to leave ; and it is not good for jobs in our countries, but you are right that if there is a serious problem with climate, we should take care of it.

  20. Nick you said that it is clear that:
    "We are changing the climate of our planet."

    See this is not clear to me. How can scientists say this? What methods do they use to measure human impact on the global climate? What type of experiments do they perform? How do they keep a control group? How do they factor in the cyclical changes in their equations? What about the effects of deforestation?

    My engineering mind requires more answers before leaning to one side or the other. I would say that I am middle. I have heard credible scientists debate both sides. I am big into recycling, biking to places, and eating little meat (large production of animals increases CO2 levels). I figure it is safe to err in the side of safety.

    But I do have a problem with legislators making rules that may have very little impact and may hurt industrializing the developing nations.

    Nick: Why is it clear to you?

    Jared: Thanks for the links. I'll check them out over the break. Does the info in the links address my questions above?

    Thank you all for your time.

  21. Thank you for an enlightening discussion. I think I need to re-examine my understanding and position on the subject.

    I have always been a fan of caring for our planet, but have been opposed to passing legislation that tries to set limits on CO_2 emissions. I think there are better ways to do it. And as you said, lowering such emissions are, regardless of future predictions, an important thing to do.

  22. I have gone back and forth on AGW for years, mostly because it can be difficult to see through the rhetoric on both sides, but continue to see red flags all over the place.

    1. I am not bothered by the use of the word 'trick.' However, I am concerned that these scientists have not been sufficiently skeptical of their own work, or in other words that they've been doing what Feynman refers to as cargo cult science. With Moscow's Institute of Economic Analysis reporting that over 40% of Russian territory (~5% of the world's land area) was not included in the HadCRUT survey, plus concerns about the dendrochronology data coming from only a tiny subset of all trees (and which happen to be those which show warming), the possibility of cherry-picking (whether intended or not) seems non-zero to me.

    On top of that (and related to your point 2), statistical fallacies, undisclosed conflicts of interest, and the complete lack of the accepted peer-review process in IPCC processes hardly inspire confidence. See

    It's one thing when trained climate scientists with PhDs make scientific claims, but (as Joe brought up) the related political and financial processes have taken on a life of their own and seem rather intent on doing what they want regardless of the science.

    Like you who blog here, I have a BS in physics from BYU and am pursuing a PhD in physics. I have a colleague who works in atmospheric science who is pretty persuasive on the science, but red flags such as the above make it pretty difficult for me to buy in completely.

  23. Though it is sort of off topic, this is what I think the government's role is: To use resources like national labs to develop clean, cheap, efficient, practical and marketable technologies which can be handed over to the private sector.

    This will accomplish wo goals:
    1. Since these new technologies are clean, cheap, efficient, practical and marketable, market forces as opposed to mandates and regulation will compel industries to back technologies which tur out to be good for the environment.
    2. The US will have yet another slew of technologies that can be exported to other countries bring even more money and jobs to the US.

    Our government has a track record of developing new technologies that end up doing wonders for the private sector. Think things like computers for example. Has that technology created jobs and earned massive amounts of income.

    In the immortal words of Sarah Palin: "You Betcha!"

  24. armk,

    I haven't found a direct answer to your first question in the links provided. However, they do explain that essentially, the relative contribution of CO2 from humans vs nature is irrelevant as Nick explained. What we know is that human contributions are pushing the CO2 concentration up. As for humans vs volcanoes, the USGS says that human CO2 release dwarfs that of volcanoes.

    Your other questions are directly addressed in both documents.

  25. For Joseph :

    "2. The US will have yet another slew of technologies that can be exported to other countries bring even more money and jobs to the US."

    It is O.K. but only if that is not pushing out of the country, because if not when you are an engineer for these technologies in the industry this means you will have to live in countries as China (with a very different language)or Indonesia which is a destination for the petrol industry for example ; and it is not so easy to live in these countries, some decide it can be good but do not suffer the situation of being a foreigner ; I do have this experience in some countries with people who have a physique and culture closer of mine, and it is already not so easy.

  26. armk,

    You are right when you say that we cannot do global climate expiraments on the earth in the same way we do in say medicine with isolated variables and a control case. The same is true of pretty much everything in astronomy. We can't take two identical stars, change say the rotation rate of one, and see how the evolve over a few billion years. In these cases you have to make some assumptions. In climate science, one uses a long (multi-thousand year) time series of data from things like tree rings, ice cores, sea-floor sediment cores, and other proxies for temperature and CO2 concentration. We look not only at the average values but the average variation on 50 to 100 year time-periods. If you do that and compare with the past 50 years, you see that there is no example anytime at least the last 2000 years that shows anything like the warming that has been seen since 1950. Climate scientists have tried to account for that warming via everything from solar activity to inaccurate thermometer readings. Statisically, there is a 90% chance that this is due to human emissions of CO2.

    As to the criticism of a lack of peer review in the IPCC report, the IPCC report is a collection and summary of previously peer-reviewed literature. The biggest problem with the IPCC report that the executive summary gets tampered with by politicians from both sides of the debate, but generally the actual report does a good job of giving a conservative review of the state of research.

  27. Ben,

    You are right that only a very small sub-sample of all trees are used in tree-ring measurements and that there are some geographic limitations from these measurements - namely that tree ring measurements don't work where there are no trees (oceans, tundra, deserts, etc.). However the uncertainty on those measurements can be and is factored into the inferred temperature measurements. Additionally, tree ring data is supplemented by a number of other proxies, all of which can be combined to further improve the data.

    Basically, all of this gets back to point I was trying to make previously - while most of the details have yet to be sorted out, the basics of the theory are in very good shape.

  28. CO2 is a lot considered but it is a heavy gas, so is staying close to the soil (what is not the best thing in order to do a greenhouse effect), but there are some others more efficient like methane about which there is not so much. Finally when I was younger it was said that the stocks of petrol were going down so something was needed to be done in order to prepare the population, what the green movement was supposed to do, but actually I think that it is going to far because it is attacking more than helping, and it is used in order to introduce bad things as well in addition to the normal message ; but I know some do only try to find the truth .

  29. Nick,

    "Statisically, there is a 90% chance that this is due to human emissions of CO2."

    90% is impressive. Where are you getting that number? How did they get that number?

    Thanks a lot.

  30. armk,

    From the IPCC's 4th report, "Most of the observed increase in globally averaged temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic (human) greenhouse gas concentrations." The IPCC defines "very likely" as greater than 90% confidence level. That comes from a conglomeration of data from peer-reviewed papers. You can find a very nice overview of the IPCC's report at:

    If you prefer the whole report it can be found at:

  31. Very good post to spread awareness among people and we all now need to take serious care about climate change as its going to be more severe day by day.


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