DATE2016-06-10 21:22:56
AUTHORSJohn Kapsomenakis (1), Panagiotis T. Nastos (2), Christos S. Zerefos (1,2,3)
  1. Research Centre For Atmospheric Physics And Climatology, Academy Of Athens, Athens (Greece)
  2. Laboratory Of Climatology And Atmospheric Environment, Department Of Geology And Geoenviroment, National And Kapodistrian University Of Athens, Greece (Greece)
  3. Navarino Environmental Observatory, (neo), Messinia (Greece)
ABSTRACTMediterranean has been determined sequentially by IPCC as one of the most vulnerable region to the anthropogenic climate change. In the present work long-term trends of annual as well as rainy season precipitation totals during the period 1951-2012 within the Mediterranean region are estimated. Our analysis is based on homogenized monthly precipitation data recorded from more than 600 stations collected by the European Climate Assessment and Dataset as well as on gridded CRU TS3.21 precipitation data. The findings of our analysis shows negative trends of the precipitation totals in a large part of the under study area during the period 1951-2012. In order to identify possible linkage between precipitation changes and changes in the general circulation, three significant climatic circulation indices of the northern hemisphere, namely the North Atlantic, the Arctic and the Mediterranean Oscillation Indices (NAOI, AOI and MOI, respectively), have been utilized and their trends are calculated. It has been found that all three indices shows increasing trends during the under study period. Besides, an anticorrelation between the precipitation totals and the indices, especially during the rainy season of the year (October-March), has been established over most of the Mediterranean. In the process, the climatic changes in the precipitation regime between the period 1961-1990 (reference period) and the period 2071-2100 (future climate) are presented using an ensemble of climate model simulations under the RCP8.5 and RCP 4.5 emissions scenarios. The already observed decreasing trend is very likely to continue till the end of 21th century. Further, we examine if the aforementioned anticorrelation is well reproduced by the ensemble of climate models and if a possible climatic change in the atmospheric circulation indices is anticipated in the future.