Latest Global Climate Forecast: 1.5 - 6.2 degrees Celsius by the end of the century

Link: Kerr 312 (5772): 351a -- Science.

Two new statistical studies that combine data sets cast doubt on soaring upper limits for projected climate change (of 9-11 degrees) during this century while eliminating any remaining doubt that there will be substantial warming. Climate modeler Gabriele Hegerl reports in this week's issue of Nature a 5% probability that climate change will be is less than 1.5 C and a 95% chance that it is less than 6.2 C. A similar study published by Annan and Hargreaves in Geophysical Research Letters found the same lower limit of 1.5 C and a 95% upper limit of 4.5 C.  This matches the long-standing estimate of 1.5-4.5 C.

These studies should not be misinterpreted.  They match the long-standing  IPCC estimates of projected increase in mean global temperature.  The studies also do not address another issue -- recent studies suggest that global ecosystems are reacting more abruptly to a given amount of climate change than we had anticipated.