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About climatesight

Kaitlin Naughten is an ocean-ice modeller at the British Antarctic Survey in Cambridge.

New Year Gratitude

A very happy 2011 to everyone. I thought I would write a New Year’s post like last year’s.

ClimateSight wouldn’t exist at all without my very best friend and partner, who, after listening for months to my rambles about climate science and policy, set me up with a blog. Since my first post, he has listened to my ideas and provided many of his own, even though he’s not particularly interested in climatology. He is also a source of balance in my life, keeping me sane when news reports and nasty comments start to overwhelm me.

Equally deep gratitude goes to the scientist who first sparked my interest in climate, and who continues to be both a mentor and a friend, as well as a library (I promise I’ll return those books sooner or later). You know who you are!

I have received advice on everything from my comment policy to my course selection from many wise climate bloggers, such as Steve Easterbrook, Michael Tobis, and Tamino, as well as countless others who prefer to read and comment than to write their own blogs – too many to name!

This year, I have become involved in Skeptical Science, a multi-faceted collaboration of scientists and science enthusiasts concerned about the state of climate change communication. It is an honour to be part of the supportive, enthusiastic community of authors, and the articles they write provide hours of fascinating reading and further research.

Last but not least, I must thank the readers and commenters over here. I feel that I get more out of this blog than I put in. My thoughts on a topic don’t end when I hit “publish” – that’s just the beginning, as insights and links to further reading invariably appear in the comments.

I am grateful for more than the people who helped to create this online community, though. I am grateful to live in the age of information when looking up the state of Arctic sea ice takes less than a minute. I am grateful to live in the age of climatology, where the field is expanding throughout virtually every discipline. Finally, strangely enough, I am grateful to live in the age of climate change, to witness this fascinating phenomenon unfold, and (hopefully) to be a part of the generation that stops it in its tracks.

Storms of my Grandchildren

I hope everyone had a fun and relaxing Christmas. Here’s a book I’ve been meaning to review for a while.

The worst part of the recent book by NASA climatologist James Hansen is, undoubtedly, the subtitle. The truth about the coming climate catastrophe and our last chance to save humanity – really? That doesn’t sound like the intrinsic, subdued style of Dr. Hansen. In my opinion, it simply alienates the very audience we’re trying to reach: moderate, concerned non-scientists.

The inside of the book is much better. While he couldn’t resist slipping in a good deal of hard science (and, in my opinion, these were the best parts), the real focus was on climate policy, and the relationship between science and policy. Hansen struggled with the prospect of becoming involved in policy discussions, but soon realized that he didn’t want his grandchildren, years from now, to look back at his work and say, “Opa understood what was happening, but he did not make it clear.”

Hansen is very good at distinguishing between his scientific work and his opinions on policy, and makes no secret of which he would rather spend time on. “I prefer to just do science,” he writes in the introduction. “It’s more pleasant, especially when you are having some success in your investigations. If I must serve as a witness, I intend to testify and then get back to the laboratory, where I am comfortable. That is what I intend to do when this book is finished.”

Hansen’s policy opinions centre on a cap-and-dividend system: a variant of a carbon tax, where revenue is divided evenly among citizens and returned to them. His argument for a carbon tax, rather than cap-and-trade, is compelling, and certainly convinced me. He also advocates the expansion of nuclear power (particularly “fourth-generation” fast nuclear reactors), a moratorium on new coal-generated power plants, and drastically improved efficiency measures.

These recommendations are robust, backed up with lots of empirical data to argue why they would be our best bet to minimize climate change and secure a stable future for generations to come. Hansen is always careful to say when he is speaking as a scientist and when he is speaking as a citizen, and provides a fascinating discussion of the connection between these two roles. As Bill Blakemore from ABC television wrote in correspondence with Hansen, “All communication is biased. What makes the difference between a propagandist on one side and a professional journalist or scientist on the other is not that the journalist or scientist ‘set their biases aside’ but that they are open about them and constantly putting them to the test, ready to change them.”

Despite all this, I love when Hansen puts on his scientist hat. The discussions of climate science in this book, particularly paleoclimate, were gripping. He explains our current knowledge of the climatic circumstances surrounding the Permian-Triassic extinction and the Paleocene-Eocene Thermal Maximum (usually referred to as the PETM). He explains why neither of these events is a suitable analogue for current climate change, as the current rate of introduction of the radiative forcing is faster than anything we can see in the paleoclimatic record.

Be prepared for some pretty terrifying facts about our planet’s “methane hydrate gun”, and how it wasn’t even fully loaded when it went off in the PETM. Also discussed is the dependence of climate sensitivity on forcing: the graph of these two variables is more or less a parabola, as climate sensitivity increases both in Snowball Earth conditions and in Runaway Greenhouse conditions. An extensive discussion of runaway greenhouse is provided, where the forcing occurs so quickly that negative feedbacks don’t have a chance to act before the positive water vapour feedback gets out of control, the oceans boil, and the planet becomes too hot for liquid water to exist. For those who are interested in this scenario, Hansen argues that, if we’re irresponsible about fossil fuels, it is quite possible for current climate change to reach this stage. For those who have less practice separating the scientific part of their brain from the emotional part, I suggest you skip this chapter.

I would recommend this book to everyone interested in climate change. James Hansen is such an important player in climate science, and has arguably contributed more to our knowledge of climate change than just about anyone. Whether it’s for the science, for the policy discussions, or for his try at science fiction in the last chapter, it’s well worth the cover price.

Thoughts from others who have read this book are welcome in the comments, as always.

An Unlikely Priority

A small news splash surfaced this week over a recent paper in Nature, regarding the prospects for Arctic sea ice and, consequently, polar bear populations. Until this paper was published, studies had only examined business-as-usual scenarios. We didn’t really know whether or not, if we pursued aggressive mitigation, it would be too late to save the polar bears from extinction.

The GCM output this paper analysed suggested that there is hope. They found the relationship between temperature and sea ice cover to be more linear, and the ice-albedo feedback in the Arctic to be weaker, than we previously thought. Tipping points where sea ice is beyond hope might not be such a problem. Therefore, we may still have a chance to limit damage to the ecosystem that experiences consequences of climate change earliest and strongest, and the polar bears might still make it. Nature News has a great summary for those who want more detail on the literature.

When the story showed up in my CBC News feed, however, I was bewildered at the angle they took:

Polar bears could be saved from extinction if greenhouse gas emissions are significantly reduced in the next decade or two, a study released Wednesday suggests.

As if that’s the most compelling reason to pursue mitigation…

Don’t get me wrong: it would be a shame to see the polar bears go. But it would be much worse to see agriculture in the subtropics go, or to see low-lying nations go. I believe that the public is wise enough to understand that sentimental notions about an oft-romanticized species are minuscule in their importance when compared to matters of human security.

Additionally, since polar bears reside at the top of the food chain, the ecological consequences of their loss – while certainly not trivial – would probably be less intense than if it were another species. Imagine the hypothetical scenario of termites going extinct – it would be much worse. Termites aren’t quite so cute and cuddly, though.

I continue to be amazed by choices that the mainstream media makes as to which studies to report on and which studies to ignore. Their picture of ordinary people’s priorities is baffling and somewhat insulting. I get it – I have a strong affinity for wildlife – but the species I care about the most is still Homo sapiens, despite its blatant shortcomings.

Just Links for Now…

I apologize for my relative silence recently. I am in the midst of studying for my first set of final exams. To tide you over until that has calmed down a bit, I will share some of the interesting pieces I have read and watched recently.

My study break today was spent watching a fantastic video that Peter Sinclair recently dug up. It’s an hour-long talk by Dr. Ben Santer (see my recent interview with him), with an introduction by the late Stephen Schneider and questions at the end. He tells a very troubling story about “science, non-science and nonsense”. Lots of great quotes in there – I highly recommend giving it a watch.

John Cook from Skeptical Science has compiled his articles and rebuttals into a gorgeous document about the evidence for anthropogenic climate change, written in accessible language with effective graphics on every page. It’s so effective, I would like to print out a few dozen of these booklets and hand them out at the university.

On RealClimate, Ray Pierrehumbert addressed the common policy option of focusing on cutting emissions of methane and soot in the short-term in order to “buy us time” to reduce carbon dioxide. In fact, because these emissions have such a short atmospheric lifetime, it doesn’t really matter whether we focus on them now or later – while concentrations of carbon dioxide, with a lifetime of centuries to millennia, highly depend on when we address it. Take a look at these projections comparing our options:

Michael Tobis, however, thinks that we should focus on non-CO2 emissions despite these realities. Short-term economic and population “crashes” due to sudden warming in the near term could conceivably be more damaging to human security, because it means that we won’t be able to afford any mitigation, further worsening the long-term emissions. Both articles are worth a read.

Well, off to go memorize organic functional groups. Enjoy!

The Nature of Scientific Consensus

Cross-posted from NextGen Journal

It is common for one to fail to grasp the difference between “consensus” and “unanimity”.

A consensus does not require agreement from absolutely every member involved. Rather, it is a more general measure of extremely high agreement, high enough to accept and base decisions on. It’s stronger than a majority-rules style of democracy, but does not necessarily equal unanimity. In fact, in the area of science, where the concept of consensus is particularly important, unanimity is nearly impossible.

With the exception of pure mathematics, scientific theories cannot be proven beyond a doubt. Every physical process that researchers study has some amount of irreducible uncertainty – because there is always, no matter how small, a chance that our understanding could be completely wrong. Additionally, science is never “settled”, because there is always more to learn, whatever the field. Even a law as basic as gravity is still being studied by physicists, and it turns out that it gets more complicated the more you look at it.

Despite this inherent uncertainty, scientists have developed consensuses around all sorts of topics. The Earth is approximately oblate-spherical in shape. Smoking cigarettes increases one’s risk of lung cancer. HIV causes AIDS. There’s a tiny chance that these statements are incorrect, but researchers can still have confidence in their accuracy. Incomplete knowledge is not the same as no knowledge.

However, when there is room for doubt, there will usually be doubters. Physicist Richard Lindzen continues to dispute the health risks of smoking (a conversation is recounted in a recent book by James Hansen). Peter Duesberg, an active molecular and cell biologist, prominently opposes the link between HIV and AIDS. Believe it or not, the Flat Earth Society was alive and well until the death of its leader in 2001 – and signs of the society’s renewal are emerging.

As these examples suggest, for a layperson to wait for scientific unanimity before accepting a topic would be absurd. When consensus reaches a certain point, the null hypothesis shifts: the burden of proof is on the contrarians, rather than the theory’s advocates.

Another case study that may seem surprising to many is that of anthropogenic global warming. A strong scientific consensus exists that human activity, mainly the burning of fossil fuels, is exerting a warming influence on the planet’s temperature, which is already beginning to show up in the instrumental record. This phenomenon is contested by less than 3% of publishing climatologists, a negligible amount of peer-reviewed scientific studies (so few that not one showed up in a 2004 survey’s random sample of almost one thousand papers), and no major scientific societies internationally. Additionally, scientists who dispute the existence or causes of climate change tend to have lower academic credibility than those who do not. It becomes apparent that this scientific question warrants “consensus” standing: never quite settled, never quite unanimous, but certainly good enough to go by. The mainstream media does not always reflect this consensus accurately, but it nonetheless exists.

As world leaders meet in Cancun this week to discuss a global policy to prevent or limit future climate change – a prospect that looks less likely by the day – science can only offer so much advice. Climatologists can approximate what levels of emissions cuts are required to prevent unacceptable consequences, but only when the governments of the world decide which consequences they are willing to accept. Can we deal with worldwide food shortages? Rising sea levels? What about a mass extinction? Even after we define “dangerous consequences”, scientists are unsure of exactly how much temperature change will trigger these consequences, as well as how much greenhouse gas emissions will need to be cut, and how quickly, to prevent the temperature change. All they can offer is a range of probabilities and most likely scenarios.

But remember, incomplete and uncertain knowledge is not the same as no knowledge. Of one thing climate scientists are sure: the more greenhouse gas emissions we emit, the more the world will warm, and the harder it will be to deal with the consequences. There’s no reason for you and I to doubt that simple correlation any longer.

New Theme!

Any thoughts on the new theme, “Pilcrow”? I chose it because it’s the most customizable you can get without paying WordPress.com to edit CSS.

The custom photo header, which I’ve wanted for a long time, is of a gorgeous mixed forest along the Ottawa River in the fall, just outside Parliament.

The Real Story of Climategate

A year ago today, an unidentified hacker published a zipped folder in several locations online. In this folder were approximately one thousand emails and three thousand files which had been stolen from the backup server of the Climatic Research Unit in the UK, a top centre for global temperature analysis and climate change studies. As links to the folder were passed around on blogs and online communities, a small group of people sorted through the emails, picking out a handful of phrases that could be seen as controversial, and developing a narrative which they pushed to the media with all their combined strength. “A lot is happening behind the scenes,” one blog administrator wrote. “It is not being ignored. Much is being coordinated among major players and the media. Thank you very much. You will notice the beginnings of activity on other sites now. Here soon to follow.”

This was not the work of a computer-savvy teenager that liked to hack security systems for fun. Whoever the thief was, they knew what they were looking for. They knew how valuable the emails could be in the hands of the climate change denial movement.

Skepticism is a worthy quality in science, but denial is not. A skeptic will only accept a claim given sufficient evidence, but a denier will cling to their beliefs regardless of evidence. They will relentlessly attack arguments that contradict their cause, using talking points that are full of misconceptions and well-known to be false, while blindly accepting any argument that seems to support their point of view. A skeptic is willing to change their mind. A denier is not.

There are many examples of denial in our society, but perhaps the most powerful and pervasive is climate change denial. We’ve been hearing the movement’s arguments for years, ranging from illogic (“climate changed naturally in the past, so it must be natural now“) to misrepresentation (“global warming stopped in 1998“) to flat-out lies (“volcanoes emit more carbon dioxide than humans“). Of course, climate scientists thought of these objections and ruled them out long before you and I even knew what global warming was, so in recent years, the arguments of deniers were beginning to reach a dead end. The Copenhagen climate summit was approaching, and the public was beginning to understand the basic science of human-caused climate change, even realize that the vast majority of the scientific community was concerned about it. A new strategy for denial and delay was needed – ideally, for the public to lose trust in researchers. Hence, the hack at CRU, and the beginning of a disturbing new campaign to smear the reputations of climate scientists.

The contents of the emails were spun in a brilliant exercise of selective quotation. Out of context, phrases can be twisted to mean any number of things – especially if they were written as private correspondence with colleagues, rather than with public communication in mind. Think about all the emails you have sent in the past decade. Chances are, if someone tried hard enough, they could make a few sentences you had written sound like evidence of malpractice, regardless of your real actions or intentions.

Consequently, a mathematical “trick” (clever calculation) to efficiently analyse data was reframed as a conspiracy to “trick” (deceive) the public into believing the world was warming. Researchers discussed how to statistically isolate and “hide the decline” in problematic tree ring data that was no longer measuring what it used to, but this quote was immediately twisted to claim that the decline was in global temperatures: the world is cooling and scientists are hiding it from us!

Other accusations were based not on selective misquotation but on a misunderstanding of the way science works. When the researchers discussed what they felt were substandard papers that should not be published, many champions of the stolen emails shouted accusations that scientists were censoring their critics, as if all studies, no matter how weak their arguments, had a fundamental right to be published. Another email, in which a researcher privately expressed a desire to punch a notorious climate change denier, was twisted into an accusation that the scientists threatened people who disagreed with them. How was it a threat if the action was never intended to materialize, and if the supposed target was never aware of it?

These serious and potentially damaging allegations, which, upon closer examination, are nothing more than grasping at straws, were not carefully examined and evaluated by journalists – they were repeated. Early media reports bordered on the hysterical. With headlines such as “The final nail in the coffin of anthropogenic global warming” and “The worst scientific scandal of our generation“, libelous claims and wild extrapolations were published mere days after the emails were distributed. How could journalists have possibly had time to carefully examine the contents of one thousand emails? It seems much more likely that they took the short-cut of repeating the narrative of the deniers without assessing its accuracy.

Even if, for the sake of argument, all science conducted by the CRU was fraudulent, our understanding of global warming would not change. The CRU runs a global temperature dataset, but so do at least six other universities and government agencies around the world, and their independent conclusions are virtually identical. The evidence for human-caused climate change is not a house of cards that will collapse as soon as one piece is taken away. It’s more like a mountain: scrape a couple of pebbles off the top, but the mountain is still there. For respected newspapers and media outlets to ignore the many independent lines of evidence for this phenomenon in favour of a more interesting and controversial story was blatantly irresponsible, and almost no retractions or apologies have been published since.

The worldwide media attention to this so-called scandal had a profound personal impact on the scientists involved. Many of them received death threats and hate mail for weeks on end. Dr. Phil Jones, the director of CRU, was nearly driven to suicide. Another scientist, who wishes to remain anonymous, had a dead animal dumped on his doorstep and now travels with bodyguards. Perhaps the most wide-reaching impact of the issue was the realization that private correspondence was no longer a safe environment. This fear only intensified when the top climate modelling centre in Canada was broken into, in an obvious attempt to find more material that could be used to smear the reputations of climate scientists. For an occupation that relies heavily on email for cross-national collaboration on datasets and studies, the pressure to write in a way that cannot be taken out of context – a near-impossible task – amounts to a stifling of science.

Before long, the investigations into the contents of the stolen emails were completed, and one by one, they came back clear. Six independent investigations reached basically the same conclusion: despite some reasonable concerns about data archival and sharing at CRU, the scientists had shown integrity and honesty. No science had been falsified, manipulated, exaggerated, or fudged. Despite all the media hullabaloo, “climategate” hadn’t actually changed anything.

Sadly, by the time the investigations were complete, the media hullabaloo had died down to a trickle. Climategate was old news, and although most newspapers published stories on the exonerations, they were generally brief, buried deep in the paper, and filled with quotes from PR spokespeople that insisted the investigations were “whitewashed”. In fact, Scott Mandia, a meteorology professor, found that media outlets devoted five to eleven times more stories to the accusations against the scientists than they devoted to the resulting exonerations of the scientists.

Six investigations weren’t enough, though, for some stubborn American politicians who couldn’t let go of the article of faith that Climategate was proof of a vast academic conspiracy. Senator James Inhofe planned a McCarthy-like criminal prosecution of seventeen researchers, most of whom had done nothing more than occasionally correspond with the CRU scientists. The Attorney General of Virginia, Ken Cuccinelli, repeatedly filed requests to investigate Dr. Michael Mann, a prominent paleoclimatic researcher, for fraud, simply because a twelve-year-old paper by Mann had some statistical weaknesses. Ironically, the Republican Party, which prides itself on fiscal responsibility and lower government spending, continues to advocate wasting massive sums of money conducting inquiries which have already been completed multiple times.

Where are the politicians condemning the limited resources spent on the as yet inconclusive investigations into who stole these emails, and why? Who outside the scientific community is demanding apologies from the hundreds of media outlets that spread libelous accusations without evidence? Why has the ongoing smear campaign against researchers studying what is arguably the most pressing issue of our time gone largely unnoticed, and been aided by complacent media coverage?

Fraud is a criminal charge, and should be treated as such. Climate scientists, just like anyone else, have the right to be presumed innocent until proven guilty. They shouldn’t have to endure this endless harassment of being publicly labelled as frauds without evidence. However, the injustice doesn’t end there. This hate campaign is a dangerous distraction from the consequences of global climate change, a problem that becomes more difficult to solve with every year we delay. The potential consequences are much more severe, and the time we have left to successfully address it is much shorter, than the vast majority of the public realizes. Unfortunately, powerful forces are at work to keep it that way. This little tussle about the integrity of a few researchers could have consequences millennia from now – if we let it.

Update: Many other climate bloggers are doing Climategate anniversary pieces. Two great ones I read today were Bart Verheggen’s article and the transcript of John Cook’s radio broadcast. Be sure to check them out!