[AAS08-P06] Influence of stratospheric dynamics on tropical convection and equatorial waves
Keywords:Stratosphere-Troposphere Interaction, Tropical meteorology
The upwelling in the lower stratosphere associated with the SSW event started around 5 January 2010, and the deep convection was formed from 8 to 14 January along 10 south degree latitude in the whole tropics (except for South American sector in the simulation) due to the negative static stability at the upper layers at TTL. In particular, the precipitation was extended longitudinally over the Indian Ocean after 8 January, which developed over high SST region across the Indian Ocean. A tropical cyclone developed within this region on 11 January. It is noted that deep convection was enhanced over the equatorial Africa on 8 and 9 January before enhancement of the longitudinally extended precipitation over the Indian Ocean. Eastward propagation of a convective coupled Kelvin waves from the Africa to the Maritime continent, might excite the longitudinally extended precipitation through a reduction of the static stability in the TTL. The convection over the Maritime continent was enhanced around 15 January when the Kelvin wave arrived there. Difference in responses of convective activity over the equatorial Africa and that over the Maritime Continent could be arose from a difference in convective characteristic in two regions such as higher cloud top altitude over Africa than that over the Maritime Continent.