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about Gavin Schmidt

Gavin Schmidt is a climate modeler, working for NASA and with Columbia University.

One year later

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I woke up on Tuesday, 17 Nov 2009 completely unaware of what was about to unfold. I tried to log in to RealClimate, but for some reason my login did not work. Neither did the admin login. I logged in to the back-end via ssh, only to be inexplicably logged out again. I did it again. No dice. I then called the hosting company and told them to take us offline until I could see what was going on. When I did get control back from the hacker (and hacker it was), there was a large uploaded file on our server, and a draft post ready to go announcing the theft of the CRU emails. And so it began.

From that Friday, and for about 3 weeks afterward, we were drafted into the biggest context setting exercise we’d ever been involved in. What was the story with Soon and Baliunas? What is the difference between tree ring density and tree ring width? What papers were being discussed in email X? What was Trenberth talking about? Or Wigley? Or Briffa or Jones? Who were any of this people anyway? The very specificity of the emails meant that it was hard for the broader scientific community to add informed comment, and so the burden on the people directly involved was high.

The posts we put up initially are still valid today – and the 1000’s of comment stand as testimony to the contemporary fervour of the conversation:

I think we did pretty well considering – no other site, nor set of scientists (not even at UEA) provided so much of the background to counter the inevitable misinterpretations that starting immediately spreading. While some commentators were predicting resignations, retractions and criminal charges, we noted that there had not been any scientific misconduct, and predicted that this is what the inquiries would find and that the science would not be affected. (Note, the most thorough inquiry, and one that will have to withstand judicial review, is the one by EPA which, strangely enough, has barely been discussed in the blogosphere).

Overall, reactions have seemed to follow predictable lines. The Yale Forum has some interesting discussions from scientists, and there are a couple of good overviews available. Inevitably perhaps, the emails have been used to support and reinforce all sorts of existing narratives – right across the spectrum (from ‘GW hoaxers’ to Mike Hulme to UCS to open source advocates).

Things have clearly calmed down over the last year (despite a bit of a media meltdown in February), but as we predicted, no inquiries found anyone guilty of misconduct, no science was changed and no papers retracted. In the meantime we’ve had one of the hottest years on record, scientists continue to do science, and politicians…. well, they continue to do what politicians do.

Solar spectral stumper

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It’s again time for one of those puzzling results that if they turn out to be true, would have some very important implications and upset a lot of relatively established science. The big issue of course is the “if”. The case in question relates to some results published this week in Nature by Joanna Haigh and colleagues. They took some ‘hot off the presses’ satellite data from the SORCE mission (which has been in operation since 2003) and ran it through a relatively complex chemistry/radiation model. These data are measurements of how the solar output varies as a function of wavelength from an instrument called “SIM” (the Spectral Irradiance Monitor).
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IPCC report card

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Update: Nature has just published a thoughtful commentary on the report

The Inter-Academy Council report on the processes and governance of the IPCC is now available. It appears mostly sensible and has a lot of useful things to say about improving IPCC processes – from suggesting a new Executive to be able to speak for IPCC in-between reports, a new communications strategy, better consistency among working groups and ideas for how to reduce the burden on lead authors in responding to rapidly increasing review comments.

As the report itself notes, the process leading to each of the previous IPCC reports has been informed from issues that arose in previous assessments, and that will obviously also be true for the upcoming fifth Assessment report (AR5). The suggestions made here will mostly strengthen the credibility of the next IPCC, particularly working groups 2 and 3, though whether it will make the conclusions less contentious is unclear. Judging from the contrarian spin some are putting on this report, the answer is likely to be no.

Information levels

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Rasmus’ recent post on the greenhouse effect raised some interesting points concerning the technical level at which posts or other public communications should be written. This was a relatively technical article as these things go, eschewing the very basic ‘the greenhouse effect is like a blanket’ but not really approaching the level of a technical paper on the subject (no line-by-line calculations for instance). Nonetheless, there were complaints that was too much to be absorbed by the lay public, counter-arguments that making it too simple was patronising, as well as complaints that the discussions were not technical enough (for instance in explaining stratospheric cooling). In these discussions there are clearly the outlines of a common debate, and perhaps a way forward in the future.

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The uncertainty prayer

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Seen at a meeting yesterday:


Grant us…
The ability to reduce the uncertainties we can;
The willingness to work with the uncertainties we cannot;
And the scientific knowledge to know the difference.

(Drawn from a white paper on the use of climate models for water managers).

Discuss.

Leakegate: A retraction

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Back in February, we commented on the fact-free IPCC-related media frenzy in the UK which involved plentiful confusion, the making up of quotes and misrepresenting the facts. Well, a number of people have pursued the newspapers concerned and Simon Lewis at least filed a complaint (pdf) with the relevant press oversight body. In response, the Sunday Times (UK) has today retracted a story by Jonathan Leake on a supposed ‘Amazongate’ and published the following apology:

The article “UN climate panel shamed by bogus rainforest claim” (News, Jan 31) stated that the 2007 Intergovernmental Panel on Climate Change (IPCC) report had included an “unsubstantiated claim” that up to 40% of the Amazon rainforest could be sensitive to future changes in rainfall. The IPCC had referenced the claim to a report prepared for the World Wildlife Fund (WWF) by Andrew Rowell and Peter Moore, whom the article described as “green campaigners” with “little scientific expertise.” The article also stated that the authors’ research had been based on a scientific paper that dealt with the impact of human activity rather than climate change.

In fact, the IPCC’s Amazon statement is supported by peer-reviewed scientific evidence. In the case of the WWF report, the figure had, in error, not been referenced, but was based on research by the respected Amazon Environmental Research Institute (IPAM) which did relate to the impact of climate change. We also understand and accept that Mr Rowell is an experienced environmental journalist and that Dr Moore is an expert in forest management, and apologise for any suggestion to the contrary.

The article also quoted criticism of the IPCC’s use of the WWF report by Dr Simon Lewis, a Royal Society research fellow at the University of Leeds and leading specialist in tropical forest ecology. We accept that, in his quoted remarks, Dr Lewis was making the general point that both the IPCC and WWF should have cited the appropriate peer-reviewed scientific research literature. As he made clear to us at the time, including by sending us some of the research literature, Dr Lewis does not dispute the scientific basis for both the IPCC and the WWF reports’ statements on the potential vulnerability of the Amazon rainforest to droughts caused by climate change.

In addition, the article stated that Dr Lewis’ concern at the IPCC’s use of reports by environmental campaign groups related to the prospect of those reports being biased in their conclusions. We accept that Dr Lewis holds no such view – rather, he was concerned that the use of non-peer-reviewed sources risks creating the perception of bias and unnecessary controversy, which is unhelpful in advancing the public’s understanding of the science of climate change. A version of our article that had been checked with Dr Lewis underwent significant late editing and so did not give a fair or accurate account of his views on these points. We apologise for this.

Note that the Sunday Times has removed the original article from their website (though a copy is available here), and the retraction does not appear to have ever been posted online. Here is a scan of the print version just in case there is any doubt about its existence. (Update: the retraction has now appeared).

This follows on the heels of a German paper, the Frankfurter Rundschau, recently retracting a story on the ‘Africagate’ non-scandal, based on reporting from….. Jonathan Leake.

It is an open question as to what impact these retractions and apologies have, but just as with technical comments on nonsense articles appearing a year after the damage was done, setting the record straight is a important for those people who will be looking at this at a later date, and gives some hope that the media can be held (a little) accountable for what they publish.

Climate Change Commitment II

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Translations: (Español)

A couple of months ago, we discussed a short paper by Matthews and Weaver on the ‘climate change commitment’ – how much change are we going to see purely because of previous emissions. In my write up, I contrasted the results in M&W (assuming zero CO2 emissions from now on) with a constant concentration scenario (roughly equivalent to an immediate cut of 70% in CO2 emissions), however, as a few people pointed out in the comments, this exclusive focus on CO2 is a little artificial.

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On attribution

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How do we know what caused climate to change – or even if anything did?

This is a central question with respect to recent temperature trends, but of course it is much more general and applies to a whole range of climate changes over all time scales. Judging from comments we receive here and discussions elsewhere on the web, there is a fair amount of confusion about how this process works and what can (and cannot) be said with confidence. For instance, many people appear to (incorrectly) think that attribution is just based on a naive correlation of the global mean temperature, or that it is impossible to do unless a change is ‘unprecedented’ or that the answers are based on our lack of imagination about other causes.

In fact the process is more sophisticated than these misconceptions imply and I’ll go over the main issues below. But the executive summary is this:

  • You can’t do attribution based only on statistics
  • Attribution has nothing to do with something being “unprecedented”
  • You always need a model of some sort
  • The more distinct the fingerprint of a particular cause is, the easier it is to detect

Note that it helps enormously to think about attribution in contexts that don’t have anything to do with anthropogenic causes. For some reason that allows people to think a little bit more clearly about the problem.
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