Characteristics of Winter Precipitation Variation over Northern Central Eurasia and Their Connections to Sea Surface Temperatures over the Atlantic and Pacific Oceans

Abstract

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 68 yr of recent precipitation records over the former Soviet Union. In addition to a general increasing trend of about 0.4 mm yr?1 or 6% decade?1 over much of the study region, three major modes of precipitation variation are identified. A quasi-biennial variation of 2?3 yr is found over the region surrounding the Caspian and Aral Seas. An El Niño timescale precipitation variation of 4?5 yr is present over southern central Siberia and is associated with eastern tropical Pacific SSTs. A quasi-decadal timescale variation of about 11?12 yr is evident over central European Russia. This quasi-decadal precipitation variation is closely linked to a major SST anomaly pattern of alternating latitudinal belts over the Atlantic and SST variations over the equatorial Pacific Ocean. These associations to SSTs are stronger at the timescales identified in this study than at an interannual timescale. The atmospheric west Atlantic pattern and atmospheric anomalies over the eastern tropical Pacific bridge the teleconnection between precipitation over central European Russia and both oceans at quasi-decadal timescales. The atmospheric anomalies over the eastern Pacific coupled with eastern tropical SST anomalies are teleconnected to those over northern Asia and, thus, are responsible for the precipitation variation over southern central Siberia at an El Niño timescale.