Tag Archives: science

Academic Culture From the Inside – a Guest Post by Steve Easterbrook

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Steve Easterbrook is a comp-sci professor at the University of Toronto who has also worked at the University of Sussex and NASA. Recently, he decided to apply his software engineering expertise to the challenge of climate change, particularly relating to climate models.

This post began as a comment on a recent RealClimate post about media coverage of the CRU hack. I liked it so much that I requested his permission to reprint it here. Enjoy!

I’m afraid to say that a lot of the personal emails between academics in any field are probably not very nice. We tend to be very blunt about what appears to us as ignorance, and intolerant of anything that wastes our time or distracts us from our work. And when we think (rightly or wrongly) that the peer review process has let another crap paper through, we certainly don’t hold back in expressing our opinions to one another.

Of course, this is completely different to how we behave when we meet one another. Most scientists seem able to distinguish clearly between the intellectual cut and thrust (in which we’re very rude about one another’s ideas) and social interactions (in which we all get together over a beer and bitch about the downsides of academic life). Occasionally, there’s someone who is unable to separate the two, and takes the intellectual jabs personally, but such people are rare enough in most scientific fields that the rest of us know exactly who they are, and try to avoid them at conferences!

Part of this is due to the nature of the academic research. We care deeply about intellectual rigor, and preserving the integrity of the published body of knowledge. But we also know that many key career milestones are dependent on being respected (and preferably liked) by others in the field, such as the more senior people who write recommendation letters for tenure and promotion and honors, or the scientists with competing theories who will get asked to peer review our papers, etc.

Most career academics have large egos and very thick skins. I think the tenure process and the peer review process filter out those who don’t. So, expect to see rudeness in private, especially when we’re discussing other scientists behind their backs with likeminded colleagues, coupled with a more measured politeness in public (e.g. at conferences).

Now, in climate science, all our conventions are being broken. Private email exchanges are being made public. People who have no scientific training and/or no prior exposure to the scientific culture are attempting to engage in a discourse with scientists, and these people just don’t understand how science works. The climate scientists whom they attempt to engage are so used to interacting only with other scientists (we live rather sheltered lives- they don’t call it the ivory tower for nothing) that they don’t know how to engage with these outsiders. What in reality is a political streetfight, we mistake for an intellectual discussion over brandy in the senior commonroom. Scientists have no training for this type of interaction, and so our responses look (to the outsiders)  rude, dismissive, and perhaps unprofessional.

Journalists like Monbiot, despite all his brilliant work in keeping up with the science and trying to explain it to the masses, just haven’t ever experienced academic culture from the inside. Hence his call, which he keeps repeating, for Phil Jones to resign, on the basis that Phil reacted unprofessionally to FOI requests. You don’t get data from a scientist by using FOI requests, you do it by stroking their ego a little, or by engaging them with a compelling research idea you want to pursue with it. And in the rare cases where this doesn’t work, you do the extra work to reconstruct it from other sources, or modify your research approach (because it’s the research we care about, not any particular dataset itself). So to a scientist, anyone stupid enough to try to get scientific data through repeated FOI requests quite clearly deserves our utter contempt. Jones was merely expressing (in private) a sentiment that most scientists would share – and extreme frustration with people who clearly don’t get it.

The same misunderstandings occur when outsiders look at how we talk about the peer-review process. We’re used to having our own papers rejected from time to time, and we learn how to deal with it – quite clearly the reviewers were stupid, and we’ll show them by getting it published elsewhere (remember, big ego, thick skin). We’re also used to seeing the occasional crap paper get accepted (even into our most prized journals), and again we understand that the reviewers were stupid, and the journal editors incompetent, and we waste no time in expressing that. And if there’s a particularly egregious example, everyone in the community will know about it, everyone will agree it’s bad, and some will start complaining loudly about the editor who let it through.

Yet at the same time, we’re all reviewers, so it’s understood that the people we’re calling stupid and incompetent are our colleagues. And a big part of calling them stupid or incompetent is to get them to be more rigorous next time round, and it works because no honest scientist wants to be seen as lacking rigor. What looks to the outsider like a bunch of scientists trying to subvert some gold standard of scientific truth is really just scientists trying to goad one another into doing a better job in what we all know is a messy, noisy process.

The bottom line is that scientists will always tend to be rude to ignorant and lazy people, because we expect to see in one another a driving desire to master complex ideas and to work damn hard at it. Unfortunately the outside world (and many journalists) interpret that rudeness as unprofessional conduct. And because they don’t see it every day (like we do!) they’re horrified.

A First Step

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Scientists are beginning to fight back against inaccurate climate change journalism, and Simon Lewis is taking one of the first steps. He officially complained to the UK Press Complaints Commission about an “inaccurate, misleading and distorted” article by Jonathan Leake in the Sunday Times.

It’s one of Leake’s many “IPCC errors uncovered” – the AR4’s claim that “up to 40% of the Amazonian forests could react drastically to even a slight reduction in precipitation”. There was a referencing error for this claim, as Daniel Nepstad explains here (citations within), but the statement is correct.

Tim Lambert contacted the scientists that Leake interviewed and discovered that three different people had told him that the claim was correct before the Times article was published – but he went ahead and called it “bogus” anyway.

Hopefully the PCC will do its job and correct the errors that were made in Leake’s article. However, the misinformation has spread beyond that. Newspapers all over the world – even the highly respected Globe and Mail – have repeated Leake’s allegations. There are a lot of ripples here that can’t be undone.

“There is currently a war of disinformation about climate change-related science, and my complaint can hopefully let journalists in the front line of this war know that there are potential repercussions if they publish misleading stories,” says Simon Lewis.

If only it were as simple as that. Still, it’s a first step.

Sea Turtles and Kids

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A true story. I found it incredibly inspiring, so I wanted to share it with all of you.

A seven-year-old girl was doing a school project on sea turtles, and found out something interesting – that the sex of a fertilized egg depends largely on the temperature in which it is laid. Climate change, therefore, could lead to too many female sea turtles and not enough males, which could further endanger the species. I did a bit of research on this myself (here’s a review paper on the subject) and am absolutely amazed that a seven-year-old was able to grasp something of this complexity.

She told her parents about it that night, and her dad’s reaction confused her. He said that he didn’t believe this theory – that he didn’t think there was any warming and so sea turtles would be just fine.

So the girl went back to school a little confused, and asked her teacher about it, and possibly did some more research, but the gist of the story is that she kept the part about climate change in her sea turtle project. And she presented it to her parents when she was done.

It gives me hope that, even in this time of rampant miscommunication and misconceptions about climate science, there are still people who know how to assess credibility. And some of them are only seven.

Staying Sane

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A long time ago, I learned to turn off the emotional half of my brain – can’t remember whether it’s right or left – when I read studies about climate change. I look at model results and projections from a purely analytical standpoint. I register how awful the scenarios are, but I don’t let it all the way in. I don’t let myself really think about the consequences. Instead, I think about how cool it is that we can study climate in this way, and how powerful math can be, so I find it quite easy to stay positive and not go completely insane.

I find this much more difficult when I read about climate change communication or policy. I think the analytical, math-loving side of my brain doesn’t have anything to do, so the full weight of the issue falls on the emotional half, and I go sort of nuts.

Take, for example, the bill that’s close to passing through the South Dakota government, requiring schools to teach climate change in a “balanced” fashion, framing it as a “largely speculative theory” that is disproven by astrology (?) Look at how US Senator James Inhofe, former Chairman of the Senate Committee on Environment and Public Works, has decided to criminally investigate 17 climate scientists with no evidence of criminal activity. Or how misconceptions spread by several British journalists have even made it into the Globe and Mail. The only misinformation that doesn’t make me angry anymore is the writing of the Heartland Institute and S. Fred Singer, because it’s so ridiculous that it seems like satire, even if it’s intended to be serious.

How do you stand it? How do you stay sane? How do you walk around all day without feeling the heavy weight of the world’s future, tossed aside by people who won’t be around to care?

I find it easy to stay happy when I only look at the scientific side of this issue. But as public communication is becoming absolutely vital for climate scientists, we can’t submerge ourselves in math anymore. Just look at how many editorials Nature has written lately on the abysmal state of climate change journalism. Even the peer-reviewed literature can’t stay separate from public communication and policy.

Most of you have been at it longer than I have. How do you cope? We’re going to need to figure it out, because our sanity is needed now more than ever.

Now We’re Talking!

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Another batch of private emails from climate scientists has been leaked/hacked/stolen/whatever. These ones, though, are very different than the last.

It’s a thread of emails from the NAS, and these guys are mad. They are mad about vested interests skewing the discussion. They are mad that journalists have sat and lapped it right up without checking their facts. They are mad that the public is suddenly more confused than ever about a field of science that is more united than ever.

They want to get hundreds of scientists to sign a declaration that yes, the anthropogenic combustion of fossil fuels is still causing the Earth to warm, and print it in newspapers like the New York Times, using only NAS money. They want to start a prime time science program on PBS. They want to have dozens of public lectures communicating climate science. They want a concise assessment report by the NAS written in layman’s terms. They want a nonprofit group to bridge communication between scientists and the public. They want “nothing short of a massive publicity campaign to educate the citizenry about what our best science is saying and why.”

“We will need funds to make something happen,” says Paul Falkowski, and by February 27th, about 15 NAS scientists had pledged $1000 each, out of their own pockets.

“How can we sit back while many of our colleagues and science as a whole is under attack?” writes Paul Ehrlich.

William Jury describes public presentations he’s given since the CRU hack, and how a common question is, “If the recent charges by anti-warming people aren’t true, why is nobody coming forth to prove it to us?”

And why not? All of us here have done our part, but it’s still not enough. I’m sure I’m not the only one who’s felt pretty powerless over the past few months. It’s incredibly obvious, to those who have all the context, that the theory of AGW is as rock-solid as ever. But truth is not enough, not when we’re up against the most effective spin machine in history. I feel like no matter how much work I put into the communication of real science, this machine will always be ten steps ahead.

Reading this string of emails gave me the most hope I’ve felt in months that we might actually be able to steer public opinion in a more accurate direction, so that we can get to work on fixing this problem. It was exhilarating to read that so many scientists are ready and willing to mobilize public communication when we need it the most. I wanted to jump up from the computer and wave my arms around and shout in joy. If I hadn’t been in the school library, I probably would have.

There has long been a stigma against communication in science – for example, Stephen Schneider faced demeaning remarks from his colleagues in the 70s for even speaking to the newspapers about his work. Couple this with the big difference between these two sides fighting for public opinion: one academic, the other political/industrial. When our academic institutions get money, they’ll spend it on research, not on public communication……while the lobby groups and oil companies are hard at work on advertising like this. (Worth a watch, it’s hilarious.)

The amount of public communication and education proposed by the NAS scientists is enormous, but it’s never been more justified than now.

Freedom of Information

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The only real issue that the hacked CRU emails brought up, the only allegation that didn’t fall apart if you were familiar with the literature (*cough cough hide the decline*), was the failure of Phil Jones to respond to some of the FOI (Freedom of Information) requests.

This looks bad on the surface, and it certainly has been spun that way – climate scientists hiding their data because they know it’s wrong and they don’t want anybody to find out. And ignoring FOI requests is a really stupid thing to do, no matter what the situation is. However, as with all the other allegations, some more context as to the nature and volume of these requests makes ignoring them understandable, if not excusable.

The Freedom of Information Act is important to a democratic society, but its major flaw is that it fails to distinguish its abuse. An article from the Sunday Times describes, in an interview with Phil Jones, what the FOI situation at CRU was.

In July 2009 alone, they received 60 FOI requests – most asking for data that was already freely available online. However, turning down a request takes 18 hours of work, and they only had 13 staff at CRU – all of which had better things to do than respond to needless FOI requests.

In another instance, over a matter of days, they received 40 FOI requests, which obviously all came from the same form letter – but each asked for data from a different 5 countries. So in total, temperature data for 200 different countries (again, most of which was already freely available) was requested, and all the forms came to CRU rather than the offices in the countries the data came from, or even the countries the authors of the FOI forms lived in. Phil Jones is sure that this coordinated attack originated at Climate Audit, which “just wanted to waste our time….they wanted to slow us down.”

Out of irritation, Phil Jones made some comments over email to his colleagues about how he wished that they could just get rid of the data rather than do all this work distributing it needlessly. This was purely a hypothetical proposition, though, as CRU doesn’t own any of the data. “We have no data to delete,” he says. “It comes to us from institutions around the world….it’s all available from other sources.”

When you are abused with FOI requests, ignoring them is not the right thing to do, and Phil Jones knows it – “I regret that I did not deal with them in the right way,” he says. His actions and words cannot be excused, but with more context, it’s obvious that his motives were not to cover up flaws in the data or hide it from critics. He just wanted to do his work.

It’s a great example of how the CRU hack compromises the professional reputations of some of the scientists involved, but it does not compromise one iota of the science. “I am obviously going to be much more careful about my emails in future, ” remarks Phil Jones. “I will write every email as if it is for publication. But I stand 100% behind the science. I did not manipulate or fabricate any data.”

CRU was not the only institution to be abused with FOI requests. The field of climate research has been grappling with this issue for the past few years. Take Benjamin Santer, for example. In a story he relays here, he describes how, following the publication of his 2008 paper, an FOI request by Stephen McIntyre asked for all the raw data used in his study so it could be replicated. Santer pointed him to the data, which was already freely available online. But then he was given two subsequent FOI requests, which asked for all of his intermediate calculations and two years of email correspondence related to the data. Obtaining this information is completely unnecessary to replicate a study, and it is certainly not normal scientific practice – the only reason you would want them would be to find material that could be framed as embarrassing and used to discredit the study and the researcher – as if Ben Santer hasn’t been through enough already. So he turned the FOI requests down, and was immediately flooded with hate mail from Climate Audit readers until he released the intermediate calculations, purely because he “wanted to continue with my scientific research…….I did not want to spend all of my available time and energy responding to harassment incited by Mr. McIntyre’s blog.”

Gavin Schmidt, a climate modeler at NASA, adds to the list of instances of FOI abuse in climate science. He remarked that “In my previous six years I dealt with one FoIA request. In the last three months, we have had to deal with I think eight…..These FoIAs are fishing expeditions for potentially embarrassing content but they are not FoIA requests for scientific information.”

James Hansen, the director of GISS at NASA, has similar opinions. Following the CRU hack, he writes, “I am now inundated with broad FOIA requests for my correspondence, with substantial impact on my time and on others in my office. I believe these to be fishing expeditions, aimed at finding some statement(s), likely to be taken out of context, which they would attempt to use to discredit climate science.”

The broad abuse of the Freedom of Information Act in the field of climate science is worrying, and it calls for some kind of caveat that will distinguish it from legitimate use of FOI. Research into climate change is vital at this point in human history, but if top researchers are forced to spend their time filling out needless paperwork instead, the field will suffer. The past few months have shown us that institutions of climate science are in need of representatives specialized in media relations. Perhaps they also need to employ dozens of students to fill out FOI forms, or lawyers to defend them from the constant attack they are under.

Recommendations?

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I’m interested in finding out how and why climate change action became a partisan issue. As Stephen Schneider says in his new book, there’s a reason that “conservation” sounds so much like “conservatism”.

The fiscal conservative school of thought is to save money for a rainy day, and to minimize spending so the economy is more sustainable in the long run – so why does this only apply to money? Money, after all, is only a representation of wealth, which – more often than not – ends up representing resources and ecosystem services, which depend on a stable climate. Conservatism, at least in our society, also tends to be more aggressive to national security threats such as terrorism. Why is climate change exempt yet again? Is it somehow any less threatening?

It seems dubious that climate change action really conflicts with conservative ideologies. How and why did it begin to be framed this way? At some point along the line, conservative media and politicians began to repeat it, to the point where it became accepted as the “party line” of the ideology, and citizens who were conservative on most other issues accepted this addition to the party line automatically.

This is why I would ideally prefer a direct democracy, as it allows citizens to vote directly on each issue, rather than just choose the party that hits the most of their requirements. We can’t just categorize people by ideology and assume that all of their opinions will fit neatly into one box. (Or three boxes at once – several flagged comments accused me of being “a Communist and a socialist and a Marxist” – is it even possible to be all three of those things at once? Don’t they have some inherent contradictions?)

I’ve stated before that my opinions on policy tend to be more social, but I’m beginning to wonder more and more how much this reflects my character and how much reflects my age. In world issues class, everyone took the Political Compass quiz, and plotted their results anonymously on a single graph so we could look at the class as a whole. Virtually everyone was in the bottom left quadrant – social libertarian. I was somewhere in the middle of those dots. Unless my class was a hotbed of radicals, it seems that ideology tends to correspond to age. Maybe it’s not because I’m a social libertarian. Maybe it’s just part of being seventeen, and as I grow older, I’ll remain somewhere near the centre of my society’s political spectrum, wherever it may fall.

Right now, at least, my opinions regarding many matters of policy fall to the left on Canada’s political spectrum. However, I view my work on climate change communication to be very separate to ideology. It began as a bid for a secure future for my generation, which is looking less and less likely. However, as the anti-action campaigns began to attack scientists and the scientific process, rather than (or in addition to) the theories and statistics themselves, I have begun to defend the nature of science, specificially climate science, instead.

I think I have the mind of a scientist, and I really want to be a scientist. Not to be a doctor/dentist/pharmacist, which is often the automatic course for high school students who are good at science and math, but to be a researcher and conduct studies and publish in journals and discover things. I feel more and more sure about this as I get older. I think this deep connection to the scientific process has given me some elements of conservatism. I am quite conservative about the process of peer-review, resist change to its structure, and hold tightly to fundamental discoveries in the field of climate science, rather than blowing off Arrhenius just because of something written in Energy & Environment.

I am not writing this blog, or pushing for climate change action and communication, for any ideology or party or political belief. I am defending both science and the future, two parties that get very little say in the political system. I am defending the mountain of evidence that many seem willing to discount entirely.  I am defending the millions of unborn citizens who have the right to a world just as good, if not better, than the one we have today.

This post has become a ramble I didn’t expect to go on – it’s late, after all, and I’m a teenager who needs her sleep. So I’ll bring it back to the beginning. Are there any recommendations as to which sources I should look at for research into how and why this became a partisan issue? Books, US politics backgrounders, Spencer Weart posts? I’d appreciate your input.

The Antithesis to Nitpicking

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Sometimes we have to step back and look at the big picture. We have to remember that not everyone has heard or believed the one about global warming stopping in 1998. Denialists centre around nitpicking and ideas that global warming is a “house of cards”, so we respond the same way: countering all the “mistakes” they claim to have found.

In reality, climate change is an incredibly robust phenomenon that we’ve known about for decades – and the basic physics behind it, for over a century. It’s not some new, shaky discovery. It’s not going to be overturned because scientists at CRU do not always say nice things about their critics.

So I was very pleased when I opened up YouTube today to see that Peter Sinclair’s latest video was all about this big picture. If I had to choose just one of his videos to share with everyone I knew, this would certainly be it. This is the kind of message we need to get out there; this is the kind of angle we need to take.

IPCC Reform

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The IPCC is far from ideal, and we knew this even before word got out that WG2 had made several minor mistakes. I’ve written about this before – here I discuss how the IPCC is naturally biased towards understating climate change: being too optimistic in its results. And here I discuss the difference in public attention when the IPCC understated central claims (such as sea level rise, Arctic sea ice melt, and emission scenarios) to when they overstated a detail that didn’t even make it into the technical summary – exactly how fast the Himalayan glaciers would melt.

Several British journalists have managed to construct several other “scandals” in the IPCC claims, which have little to no merit. Tim Lambert has spent the past few weeks investigating the legitimacy of these allegations, and one thing stands out above all others: facts do not matter in the way the media reports alleged IPCC mistakes or misconduct. One journalist in a minor British paper can make an erroneous claim that shouts “IPCC scandal”, and even after scientists have patiently explained, multiple times, why it is untrue, the claim is repeated in every major newspaper in the world. Consequently, even though virtually all of these “scandals” have to do with the WG2, the opinion pages use it as an excuse to vehemently question the idea that humans are causing the Earth to warm. This is obviously WG1 material, which is based on the laws of physics and decades of peer-reviewed science – but that doesn’t matter to the media, does it?

For people like us, who are so intent on scientific accuracy, it is incredibly frightening when accuracy becomes irrelevant in the sources that virtually everyone else relies on for climate change information. Even after factual errors that fundamentally change the message of the story are pointed out, no retraction is printed, and the authors are dealt no consequences. As scientists and concerned citizens, our greatest weapon is truth. But that can no longer be enough – not when our fourth estate drops its responsibility to truth, at least for this issue.

The IPCC was formed in the late 80s, and the relationship between climate science and the rest of the world has changed fundamentally since then. We have gained much more understanding of what climate change could mean for the world, so creating a document that encompasses absolutely everything we know is longer and more tedious. Governments fearful of climate change action have abused their powers of IPCC editing and review, as Stephen Schneider describes in his excellent book Science as a Contact Sport. Special interests muddled the lines of communication between scientists and the public, and when, due to the Internet, this communication became impossible to stop, the special interests decided to smear the reputations of scientists, scientific organizations, and science itself. The media and the public fell willingly to this muddling and smearing, so these special interests have gained far more influence than truth should allow them.

Is it necessary, or even desirable, to reform the structure of the IPCC to better suit its communication with the public? In terms of producing the most accurate science, I feel that it’s doing just fine the way it is, with the exception of needing some new WG2 review editors, and a delayed deadline for the WG2 and WG3 publications (instead of having all three reports released simultaneously).

Nature recently published recommendations from five diverse climatologists as to how to reform the IPCC. Subscription or payment is needed to read the full article, so I’ll give a quick summary here:

Mike Hulme wants to split the IPCC into three – a Global Science Panel that frequently publishes smaller reports about WG1 topics, five or ten Regional Evaluation Panels that report on region-specific WG2 topics, and a Policy Analysis Panel that frequently publishes examinations of different policy options.

Eduardo Zorita wants the IPCC to employ full-time scientists, instead of doing all the work on a volunteer basis.

Thomas Stocker wants the IPCC to stay the way it is, but to pay extra attention to following their self-imposed rules.

Jeff Price wants to select more lead authors to produce “short, rapidly prepared, peer-reviewed reports” instead of a set of massive ones every six years.

John Christy wants the IPCC to be removed from UN oversight and adopt an open, continually updating “Wikipedia” structure. I think a more accurate allusion to Christy’s proposition is the Encyclopedia of Earth, which has lead authors and a basic review system.

Personally, I agree with Jeff Price’s proposal. Mike Hulme’s seems to be very similar, and I like the way he separates and organizes the different panels. John Christy’s idea of a continually updating report intrigues me, but the more open approach to peer-review and a policy to “hear all sides” could easily be abused through artificial balance – equality over accuracy.

Any thoughts, further suggestions, background information to share? What changes, if any, should be made to the IPCC? And how can we possibly immunize the public to this incredible excuse to be misled?

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How to Prove Global Warming Wrong

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Over the past twenty years, vested interests and political lobby groups have done a fantastic job confusing the public about anthropogenic climate change. To many, they seem to have proven the whole theory wrong.

But how could you actually prove global warming wrong – not just in the minds of the public, but through the established scientific process? What scientific discoveries – if they held up through peer-review, further criticism, and replication – would render climate change a non-problem?

One of the surest ways to stop all this cap-and-trade discussion would be to disprove the greenhouse effect itself – the mechanism by which the Earth absorbs and emits the same energy multiple times, due to the presence of greenhouse gas molecules that “bounce it back”. This keeps the Earth substantially warmer than it would be otherwise. Additionally, if the concentrations of greenhouse gases increase, so will the temperature of the Earth. This process was first hypothesized by Joseph Fourier in 1824, and was experimentally confirmed by John Tyndall in 1856. The first prediction of eventual man-made global warming came from Svante Arrhenius, in 1896. It wasn’t a theory as much as a logical result of a theory, one that was deeply rooted in physics and chemistry.

Unless our understanding of entire fields of physical science is totally off base, we can be sure that our greenhouse gas emissions will cause climate change eventually. But hey, if you could overturn all of thermodynamics, you wouldn’t have to worry about carbon taxes.

  • Cheap-out option: Svante Arrhenius was Swedish, but his name sounds sort of Russian, and 1896 wasn’t very long before the Russian Revolution. Therefore, Arrhenius was a Communist, and none of his scientific work can be trusted.

Knowing that something is sure to happen eventually, though, is different from knowing that it is happening right now with substantial speed. We know that the Earth is warming – even if you found some statistical way to disprove three separate temperature records, the physical and biological systems of our planet still stand: 90% of observed changes in the natural world, like the blooming of flowers, the peak flows of rivers, and the spawning of fish, are in the direction expected with warming (Rosenzweig et al, 2008).

But how do we know that the warming is caused by us? Climate change has been caused many times in the past by factors unrelated to greenhouse gases – like solar influences, whether they’re direct (a change in solar output) or indirect (a change in the Earth’s orbit). How do we know that’s not happening now?

If the warming was caused by the sun, the atmosphere would warm uniformly at all levels. However, if the Earth was warming from greenhouse gases, the troposphere (the layer of the atmosphere closest to the planet) would warm while the stratosphere (the next level up) would cool. This is because more heat is getting bounced back to the surface by greenhouse gases, and is subsequently prevented from reaching the stratosphere.

A cooling stratosphere has been described as the “fingerprint” evidence of greenhouse-induced warming. And, in fact, the stratosphere has been cooling over the past 30 years (Randel et al, 2009). Therefore, if you could somehow show that something else was causing this pattern of a warming troposphere and a cooling stratosphere, and that the significant, anthropogenic rise in greenhouse gases was somehow not affecting it, you would have a case for global warming being natural.

Update (18/2/10): About half of this cooling can be attributed to ozone depletion, and the other half can be attributed to greenhouse gases (NOAA, 2006). The flat trend in stratospheric temperatures from 1995-2005 (see the Randel citation above) can be explained by the recovery of ozone, which is temporarily offsetting the greenhouse gases. Interesting how the temperature of the stratosphere has just as many factors as the temperature of the troposphere…..but in both cases, you can’t explain the temperature trends without including human activity. Scott Mandia has a great explanation here.

  • Cheap-out option: Omit the explanation of why greenhouse warming causes stratospheric cooling. Just point to the graph that goes down and say, “The atmosphere is cooling! Therefore, the IPCC is a hoax!”

Finally, even if you couldn’t disprove that global warming is expected, observed, and anthropogenic, you could still show that it isn’t very significant. The way to do this would be to show that climate sensitivity is less than 2 C. Climate sensitivity refers to the amount of warming that would result from a doubling of carbon dioxide equivalent, and 2 C is generally accepted as the maximum amount of warming that our society could endure without too much trouble. The current estimates for climate sensitivity, in contrast, average around 3 C (a range of 2-4.5), and it is very unlikely to be less than 1.5 C (IPCC AR4).

However, a climate sensitivity of less than 2 C only means that climate change isn’t a problem if our greenhouse gases stop at a doubling of carbon dioxide equivalent from pre-industrial levels. Even without taking methane and other greenhouse gases into account, this brings us to a CO2 concentration of 560 ppm, which we are well on track to surpass, even with cap-and-trade. So you’d have to argue for a climate sensitivity of even less. Seeing as we’ve already warmed 0.8 C, it doesn’t leave you with a lot of wiggle room.

  • Cheap-out option: Build a climate model that does what you want it to, without any regard for the laws of physics. ExxonMobil will probably sponsor the supercomputers. Widely publicize the results and avoid peer-review at all costs.

Daunting tasks, certainly. But if you really believe that global warming is natural/nonexistent/a global conspiracy, this is the way to prove it. If you managed to prove it, and change the collective mind of the scientific community (not just the public), you’d probably win a Nobel Prize. So it’s certainly worth your time and effort.