Interdecadal change of Eurasian snow, surface temperature, and atmospheric circulation in the late 1980s

Abstract

Boreal winter and spring snow cover extent and snow water equivalent over Eurasia experienced an obvious decrease in late 1980s. A concurrent surface warming is observed over the North Atlantic and Eurasia. The present study documents the relationship among the interdecadal changes in snow, surface air temperature, and wind and the plausible reason for this change. Analysis shows that the snow decrease contributes to the temperature increase only in some limited regions and that the surface warming is largely related to the change in atmospheric circulation. The effect of atmospheric circulation change on surface warming is manifested in wind-induced heat advection and cloud-radiation changes. The wind changes over the North Atlantic and Eurasia feature a wave train with an anomalous anticyclone over Europe and anomalous southerly winds over midlatitude east Europe and Asia. The anomalous southerly winds contribute to surface warming through advection of warmer air from lower latitudes. The anomalous anticyclone contributes to surface warming over Europe through anomalous warm advection by bringing warmer air from ocean and enhanced downward shortwave radiation by suppressing upward motion. The wave pattern appears to be connected to equatorial Atlantic warming. Warmer sea surface temperature (SST) in the equatorial Atlantic Ocean enhances convection and induces a lower level anomalous cyclone to the northwest of the SST warming. The role of equatorial North Atlantic SST increase in the formation of the wave train over Eurasia is supported by numerical experiments with an atmospheric general circulation model.

Eurasian snow depth in long-term climate reanalyses

“…Reciprocally, as a corresponding component of the climate system, the snow cover influences large-scale climate patterns and has been tapped as a source of predictability at the subseasonal-to-seasonal scale, especially over Eurasia in au-M. Wegmann et al: Eurasian snow depth in long-term climate reanalyses tumn and winter (Cohen and Entekhabi, 1999;Jeong et al, 2013;Orsolini et al, 2013;Wu et al, 2014;Ye et al, 2015,).…”

Climate Change in the Kola Peninsula, Arctic Russia, during the Last 50 Years from Meteorological Observations

“…Several different processes are thought to contribute to the amplification (Cohen et al 2014, and references therein): they include local drivers, such as changes in the strength of the snow-ice-albedo feedback mechanism due to the reduction in Arctic sea ice extent, and also broad-scale circulation changes, such as increased poleward heat advection from lower latitudes (e.g., Ye et al 2015).…”

“…Similarly, phenological data have revealed an increase in the length of the thermal growing season in the Kola Peninsula from 1951 to 2012, due to both an earlier onset and later finish (Blinova and Chmielewski 2015). Although relatively little has been published in the mainstream scientific literature specifically about the Kola Peninsula climate, it has been included in large-scale studies encompassing the whole of Eurasia (e.g., Bulygina et al 2009;Ye et al 2015). Franzke (2012) examined the significance of SAT trends of varying length at individual meteorological stations within this broader region using a number of different statistical tests.…”

Spatiotemporal variability of snow depth across the Eurasian continent from 1966 to 2012

“…The amount of snowfall can be affected by climate change and leads to differences in snow depth at different times (Ye et al, 1998;Kitaev et al, 2005;Ma and Qin, 2012). In addition to air temperature and precipitation, atmospheric circulation is a key factor affecting snowfall and snow depth change (Cohen, 2011;Zhao et al, 2013;Ye et al, 2015). Those factors above and related uncertainties may explain the regional and temporal differences in long-term mean snow depth and snow depth change.…”