Recent land surface air temperature trends assessed using the 20th Century Reanalysis



[1] Land surface air temperature trends observed during 1979–2008 are compared with those simulated by the 20th Century Reanalysis that is driven only by observed sea surface temperatures and sea ice, atmospheric CO2 concentrations, solar and volcanic forcings, and surface pressure data. On a global annual average, the 20th Century Reanalysis simulates a little more than 80% of the observed trend, but with substantial regional and seasonal variations. The remainder of the trend may be ascribed tentatively to land use changes, aerosol increases and decreases, and changes in minor greenhouse gases not accounted for in the 20th Century Reanalysis.