The Dominant Modes of Spring Land Surface Temperature Over Western Eurasia and Their Possible Linkages With Large‐Scale Atmospheric Teleconnection Patterns

Abstract

AbstractPrevious studies suggest that the spring land surface temperature (LST) anomaly over Western Eurasia (WEA; 20°N–70°N, 0–70°E) is a potential driver for Asian even global climate. However, the interannual variability of LST over WEA together with its causes has not received enough attention. Based on multi‐source observations and reanalysis data, three dominant modes of spring LST over WEA were identified, and the roles of atmospheric teleconnection patterns in LST anomalies via altering cloud and water vapor were investigated from the perspective of surface energy budget. The first empirical orthogonal function (EOF1) mode exhibits a homogeneous warming pattern that is closely related to a negatively in‐phase combination of the Scandinavian and East Atlantic/Western Russia (EA/WR) patterns. Under the control of a predominant anomalous anticyclone, the warming is the result of enhanced downward longwave radiation due to more water vapor in a warmer atmosphere associated with anomalous southerly and more incident solar radiation due to reduced cloud cover. The EOF2 mode, which displays a meridional dipole structure, is dominated by the North Atlantic Oscillation. Coupled with an anomalous cyclone and anticyclone over western Europe and around the Caspian Sea, respectively, the former LST anomalies are primarily caused by cloud‐shortwave radiation processes, whereas the latter are dominated by downward longwave radiation due to water vapor. The EOF3 mode, characterized by a zonal dipole pattern, is dominated by the water vapor greenhouse effect related to the Eurasian pattern. The results of the study may provide a valuable signal for climate prediction.