The most important indicator of global warming, by far, is the land and sea surface temperature record. This has been criticized in several ways, including the choice of stations and the methods for correcting systematic errors. The Berkeley Earth Surface Temperature study sets out to do a new analysis of the surface temperature record in a rigorous manner that addresses this criticism. We are using over 39,000 unique stations, which is more than five times the 7,280 stations found in the Global Historical Climatology Network Monthly data set (GHCN-M) that has served as the focus of many climate studies.
Our aim is to resolve current criticism of the former temperature analyses, and to prepare an open record that will allow rapid response to further criticism or suggestions. Our results include not only our best estimate for the global temperature change, but estimates of the uncertainties in the record.