Spatiotemporal patterns of changes in maximum and minimum temperatures in multi-model simulations

This paper analyzes and attributes spatial and temporal patterns of changes in the diurnal cycle of land surface air temperature in 20 simulations from 11 global coupled atmosphere-ocean general circulation models during the 20th century and the 21st century under the SRES A1B scenario. Most of the warming in the maximum (Tmax) and minimum (Tmin) temperatures from 1900 to 2099 is attributed to enhanced surface downward longwave radiation (DLW), while changes in surface downward shortwave radiation (DSW) and cloud cover mainly contribute to the simulated decrease in the diurnal temperature range (DTR). Although the simulated DTR decreases are much smaller than the observed during the 20th century, the models unanimously predict substantial warming in both Tmax and Tmin and decreases in DTR, especially in high latitudes during the 21st century, in response to enhanced global-scale anthropogenic forcings (particularly greenhouse effects of atmospheric water vapor and in part aerosol radiative cooling in the tropics) and increased cloudiness in high latitudes.