Contrasting Eurasian spring and summer climate anomalies associated with western and eastern Eurasian spring snow cover changes

Abstract

Spring snow cover variations over Eurasia consist of a same-sign component and a west-east dipole component. The same-sign component is dominant during late 1970s through 1980s, and the two components are equally important during 1990s and 2000s. Present study contrasted Eurasian spring and summer climate anomalies associated with western and eastern Eurasian spring snow cover variations and between 1975-1989 and 1993-2007 and found notable differences and obvious interdecadal changes in Eurasian climate anomalies. After 1990, spring surface temperature anomalies display an obvious west-east contrast pattern, consistent with a prominent atmospheric wave pattern over Eurasia. The temperature anomalies are larger corresponding to western than eastern Eurasian snow cover change. Snow-albedo effect plays a main role in temperature change during 1975-1989, whereas atmospheric processes also contribute largely to temperature change during 1993-2007. Large soil moisture anomalies occur corresponding to western Eurasian snow cover and during [1975][1976][1977][1978][1979][1980][1981][1982][1983][1984][1985][1986][1987][1988][1989]. The snow-hydrological effect on summer precipitation is mainly detected over the West Siberian Plain where soil moisture anomalies persist over 3 months. Over most of other Eurasian regions, atmospheric circulation pattern plays a dominant role in summer surface temperature and precipitation variations. The relationship of Indian summer rainfall to western Eurasian spring snow cover was weakened since the mid-1990s, and the correlation of Northeast China summer rainfall with local spring snow cover changed from positive to negative around 1990.

Attribution of spring snow water equivalent (SWE) changes over the northern hemisphere to anthropogenic effects

“…However, remarkable increasing trends were observed for the southern part of east Eurasia, mainly due to significant increases in accumulated precipitation from the previous winter to spring period. The increases in spring SWE for east Eurasia for the last few decades are consistent with the findings by Bulygina et al (2009Bulygina et al ( , 2011 and Wu et al (2014), based on spring SCE and/or SWE.…”

Formation of Snow Cover Anomalies Over the Tibetan Plateau in Cold Seasons

“…Snow is an important component in the climate system. The snow variability affects the surface energy budget, the water cycle, and local and remote atmospheric circulation (Bamzai & Shukla, ; Barnett et al, ; Cohen & Rind, ; Kripalani et al, ; Kripalani & Kulkarni, ; Wu et al, ; Wu & Kirtman, ; Yasunari et al, ; Zhao et al, ). The Tibetan Plateau is covered by snow in most of the year (Pu et al, ; Wang, Wu, & Huang, ).…”

Low‐frequency snow changes over the Tibetan Plateau

“…The snowmelt has an immediate influence on the water cycle, especially in mountain, arid, and semiarid regions (Barnett et al, 2005). Snow change may affect atmospheric circulation and regional precipitation (Bamzai and Shukla, 1999;Chen and Wu, 2000;Zhang et al, 2004;Dash et al, 2005;Wu and Kirtman, 2007;Zhao et al, 2007;Wu et al, 2010;Si and Ding, 2013;Wu et al, 2014aWu et al, , 2014bZhu et al, 2015).…”