Precipitation over Sardinia (Italy) during the 1946-1993 rainy seasons andassociated large-scale climate variations

The interannual and decadal variability of seasonal precipitation (October through April) over Sardinia (Italy) is analysed for the years 1940-1995. I t is shown that the area-average seasonal rainfall total can vary greatly f rom one year to the next. The spatial correlation of Sardinia seasonal rain fall with that of neighbouring Mediterranean regions is generally high, tho ugh the correlation is less to the south of Sardinia, suggesting other tele connection structures may operate there. Over a slightly shorter period (1946-1993), correlations between precipitat ion and large-scale variables (sea level pressures (SLP), 500 hPa geopotent ial heights (2500) and sea surface temperatures (SST)) are calculated and a nalysed. Clear connections between the North Atlantic Oscillation (NAO) and Sardinian precipitation are found and studied. Contrasting Atlantic storm tracks were found for the wet and dry seasons. In the wet years, the track is weaker over the North Atlantic (consistent with the NAO association), wh ile over Europe there emerges a second minor storm track that enters the Me diterranean basin. In dry years this latter feature is less evident and is diverted to the lee of Sardinia, probably because of stronger intensity of the Azores High. Some apparent associations with other Northern Hemisphere remote teleconnections and large-scale structures also emerge, including th e North Pacific and across North Africa. Copyright (C) 2000 Royal Meteorolo gical Society.