Sunday, 13 December 2009


At first I thought Climategate was a storm in a teacup. I thought about it some more when Bill Easterly jumped in. (See also his interesting comparison with growth econometrics.) So I got reading. Two enjoyable blogs on climate science provided my jumping-in point: (which is, roughly speaking, pro-global-warming) and (which is roughly anti). I enjoyed finding out how you can inform yourself on this hottest of all topics, and the strengths and weaknesses of the different resources available (scientific papers, blogs and the mainstream media).

Thoughts so far.
  • I don't think the emails can be dismissed as scientists using robust language among themselves. For instance, some have said that the now-infamous phrase "trick to hide the decline" just means a technically clever piece of work. Climateaudit goes into the details, and on their analysis, the trick was not innocuous - it made the science look more settled than it was for the 3rd IPCC report. Similarly, it's wrong (and illegal?) to delete emails or files if you are afraid of a freedom of information request.
  • There seem to have been serious problems with the original "hockey stick" graph. Trying as best I could to read through the scientific papers on this, I thought that Mcintyre and McKittrick were fairly convincing.
  • The hockey stick controversy (which is the context for the most controversial UEA emails) doesn't seem to bear much on whether global warming is happening. We know it is because we have data from weather stations around the world for the past century. The debate is about whether there was a "medieval warm period" when the earth was hotter than today or if today's global warming is unique (since 1000AD). (See here and here for more details.)
  • Even if the medieval era was hotter than today, that wouldn't prove global warming doesn't matter. (The 13th century saw the Black Death, after all.)
  •  There seem to be plenty of other reasons to believe that global warming is real, and that CO2 contributes, and that this might cause severe problems for many parts of the world if we don't stop it. I haven't found anything that persuades me otherwise.
  • ... actually, I think Jon Stewart sums up better than I could.