Mediterranean precipitation climatology, seasonal cycle, and trend as simulated by CMIP5 ...

• Main Authors: Kelley, Colin Patrick, Ting, Mingfang, Seager, Richard, Kushnir, Yochanan
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Columbia University 2012
• Subjects: Climatic changes; North Atlantic; North Atlantic oscillation
• Online Access: https://dx.doi.org/10.7916/d8cj8q5x; https://academiccommons.columbia.edu/doi/10.7916/D8CJ8Q5X

Winter and summer Mediterranean precipitation climatology and trends since 1950 as simulated by the newest generation of global climate models, the Coupled Model Intercomparison Project phase 5 (CMIP5), are evaluated with respect to observations and the previous generation of models (CMIP3) used in the Intergovernmental Panel on Climate Change Fourth Assessment Report. Observed precipitation in the Mediterranean region is defined by wet winters and drier summers, and is characterized by substantial spatial and temporal variability. The observed drying trend since 1950 was predominantly due to winter drying, with very little contribution from the summer. However, in the CMIP5 multimodel mean, the precipitation trend since 1950 is evenly divided throughout the seasonal cycle. This may indicate that in observation, multidecadal internal variability, particularly that associated with the North Atlantic Oscillation (NAO), dominates the wintertime trend. An estimate of the observed externally forced trend shows ...