Influence of stratospheric sudden warming and vortex intensification on the tropical troposphere

Influence of the stratospheric sudden warming (SSW) and vortex intensification (VI) on the tropical troposphere in boreal winter is examined from the observational data. It is found that tropical convection tends to shift from northern to southern (southern to northern) hemisphere tropics associated with the occurrence of SSW (VI). The convective pattern appears is found to be very similar between the SSW and VI. The mechanism of such reaction in the tropics is also examined. It is found that the convective activity in the tropics associated with the occurrence of the SSW or VI is created by southward propagating planetary waves associated with upward propagating ones that create SSW or VI in the stratosphere.