A link between cold events in Moscow, Russia, in winter and daily anomalies of sea ice concentration in the Barents Sea

摘要

Time series of winter daily sea ice concentration (SIC) anomalies in the north-east, central and south-east part of the Barents Sea (BS) for the entire 1979-2015 period, as well as for two sub periods, 1979-1999 and 2005-2015, the latter characterized by lowest anomalies of SIC in BS were calculated. Joint analysis of the data on SIC and daily anomalies of surface air temperature (SAT) in winter in Moscow for the 1979-1999 and 2005-2015 periods was carried out. Correlation coefficients between the time series of daily SAT anomalies in Moscow and SIC in the specified BS regions for 1979-1999 and 2005-2015 were calculated. Averaged for 1979-1999 and 2005-2015 variations of daily anomalies of SIC in the south-east BS region and variation of daily SAT anomalies in Moscow were calculated and compared. Correlation functions between the variation of winter SIC in the south-east BS and the variation of SAT in Moscow for the lead/lag range -30...30 days for 1979-1999 and 2005-2015 periods were calculated. Analysis of the fields of geopotential height (GPH) anomaly at 850 mb and SAT anomaly in Eurasia in 2005-2015 relative to 1979-1999 for composites of the days with strong SIC anomaly in winter (lower 10 percentile of probability density function of SIC in winter) in the south-east part of BS was carried out. The influence of the strong negative daily SIC anomalies in the south-east of BS on formation of GPH and SAT anomalies over East Europe was revealed and regions where GPH maxima and SAT minima localized were determined.