Nov 3, 2012

Fingerprints of changes in annual and seasonal precipitation from CMIP5 models over land and ocean

Beena Balan Sarojini, Peter A. Stott, Emily Black, Debbie Polson
Geophysical Research Letters
  • Compares annual and seasonal changes in precipitation over land and ocean since 1950 simulated by the CMIP5 (Coupled Model Intercomparison Project, phase 5) climate models in which natural and anthropogenic forcings have been included
  • Finds that clear global‐scale and regional‐scale changes due to human influence are expected to have occurred over both land and ocean, which includes moistening over northern high latitude land and ocean throughout all seasons and over the northern subtropical oceans during boreal winter
  • Shows that this signal of human influence is less distinct when considered over the relatively small area of land for which there are adequate observations to make assessments of multi‐decadal scale trends
  • These results imply that extensive and significant changes in precipitation over the land and ocean may have already happened, even though, inadequacies in observations in some parts of the world make it difficult to identify conclusively such a human fingerprint on the global water cycle