Robust comparison of climate models with observations using blended land air and ocean sea surface temperatures
Kevin Cowtan, Zeke Hausfather, Ed Hawkins, Peter Jacobs, Michael E. Mann, Sonya K. Miller, Byron Steinman, Martin B. Stolpe, Robert G. Way
Overview
Climate models are used to estimate future global warming, and can be checked against the global warming we have seen so far. Most comparisons suggest that the world is warming a little more slowly than the model projections.
We show that this arises in part from the way the comparison is performed, because the methods used in constructing the historical temperature record are different from those used for the models. When we do a like-with-like comparison the discrepancy is reduced by a third, or completely eliminated if the warming fluctuation of the last decade is omitted.
This web site provides material relating to the paper "Robust comparison of climate models with observations using blended land air and ocean sea surface temperatures", published in Geophysical Research Letters.
For more details and background information, see the Briefing document.
If you would like to access the data and methods from the paper, follow the Methods and data link.
Update: Santer et al (2000) also calculated blended surface temperatures from models for comparison against observations, predating our work by 15 years.