Teleconnections of winter precipitation over northern central Eurasia to sea surface temperatures over the Atlantic and Pacific oceans

This study reveals spatial and temporal characteristics of precipitation variability and their teleconnections to sea surface temperatures (SSTs) over the Atlantic and Pacific oceans by analyzing recent 68-year precipitation records over the former Soviet Union. In addition to a general increasing trend of about 0.4 mm per year or 6% per decade over much of the study region, three major modes of precipitation variation are identified. An El Nino time scale precipitation variation of about 4 years is present over southern central Siberia and is associated with eastern tropical Pacific SSTs. A quasi-decadal time scale variation of about 12.5 years is evident over central European Russia. This quasi-decadal precipitation variation is closely linked to a major SST anomaly pattern at alternative latitudinal belts over the Atlantic and SST variations over the equatorial and tropical Pacific Ocean. An inter-decadal time scale variation of about 33 years is found over southwestern Russia and is connected to SSTs over the northwestern North and western tropical Pacific and the coasts of northern North America and northern Europe over the Atlantic. These associations to SSTs are stronger at identified oscillation time scales than at an interannual time scale. The patterns of SSTs teleconnected to precipitation are not sensitive to different SST data sets derived from different reconstruction methods. The trends in Pacific SSTs are likely to be part of inter-decadal and longer time scale variations. The atmospheric West Atlantic pattern bridges the teleconnection between precipitation over central European Russia and both oceans at quasi-decadal time scales. The trends in geopotential heights suggest the strengthening of jet streams and westerlies in the middle troposphere over the Atlantic Ocean and the Eurasian continent, and thus are likely responsible for the observed trends in precipitation.