Will a penalty be called for Keith Briffa’s excessively curved hockey stick?
Climategate, the 2009 exposure of misconduct at the University of East Anglia, was a terrible blow to the reputation of climatology, and indeed to that of British and American science. Although that story hasn’t been in the news in recent months, new evidence of similar scientific wrongdoing continues to emerge, with a new scandal hitting the climate blogosphere just a few days ago.
And central to the newest story is one of the Climategate scientists: Keith Briffa, an expert in reconstructing historical temperature records from tree rings. More particularly, the recent scandal involves a tree-ring record Briffa prepared for a remote area of northern Russia called Yamal.
For many years, scientists have used tree-ring data to try to measure temperatures from the distant past, but the idea is problematic in and of itself. Why? Because tree-ring data reflect many variables besides temperature. Russian tree growth, like that of trees around the world, also reflects changes in humidity, precipitation, soil nutrients, competition for resources from other trees and plants, animal behavior, erosion, cloudiness, and on and on. But let’s pretend, if only for the sake of argument, that we can reliably determine the mean temperature 1,000 years ago or more using tree cores from a remote part of Russia. The central issue that emerges is: How do you choose the trees?