This paper presents the surface cooling trend observed in spring along East Asia coast after the late 1990s,in contrast to the global warming trend.This surface cooling trend is comprehensible as it agrees well with t...This paper presents the surface cooling trend observed in spring along East Asia coast after the late 1990s,in contrast to the global warming trend.This surface cooling trend is comprehensible as it agrees well with the cooling of sea surface temperature(SST)in the northwestern Pacific and the weakening of 300 hPa East Asian jet(EAJ)during spring.Moreover,this cooling phenomenon has been shown to be related to the rapid decline of Arctic sea ice cover(SIC)in previous autumns.The Arctic SIC signals in previous autumns can continue in spring and act as enhanced moisture sources that support the increased snow cover in Siberia during spring.The increased Siberian snow cover possibly favors the southward invasion of cold air masses via strong radiative cooling and large-scale descending motion,which may contribute indirectly to the reduction of temperature in East Asia.In addition,three climate models that can reproduce well the East Asian spring surface cooling observed in the past predicted uncertainty in the spring temperature projection in the next decade.展开更多
基金supported by the National Natural Science Foundation of China(41130103 and 41210007)the CAS-CSIRO Cooperative Research Program(GJHZ1223)
文摘This paper presents the surface cooling trend observed in spring along East Asia coast after the late 1990s,in contrast to the global warming trend.This surface cooling trend is comprehensible as it agrees well with the cooling of sea surface temperature(SST)in the northwestern Pacific and the weakening of 300 hPa East Asian jet(EAJ)during spring.Moreover,this cooling phenomenon has been shown to be related to the rapid decline of Arctic sea ice cover(SIC)in previous autumns.The Arctic SIC signals in previous autumns can continue in spring and act as enhanced moisture sources that support the increased snow cover in Siberia during spring.The increased Siberian snow cover possibly favors the southward invasion of cold air masses via strong radiative cooling and large-scale descending motion,which may contribute indirectly to the reduction of temperature in East Asia.In addition,three climate models that can reproduce well the East Asian spring surface cooling observed in the past predicted uncertainty in the spring temperature projection in the next decade.
