AGS-PRF: Refining the Climate Role of Tropical Cyclones: Key Constituents of the Hadley Cell?

Schenkel Benjamin A, Albany NY

Investigators

Abstract

Recent research on the relationship between tropical cyclones (TC) and climate, suggests that years with enhanced TC activity may lead to decreased atmospheric poleward heat transports during the following winter possibly due to significant atmospheric poleward heat transports by TCs. Supporting this hypothesis are several studies showing that TCs are responsible for significant short-term reductions in hemispheric zonal available potential energy due to poleward moist static energy transports by TCs. Past research by the Principal Investigator (PI) has also shown that Western North Pacific TCs are responsible for significant cross-hemispheric transports of dry static energy into the Southern Hemisphere. In this project, the PI will undertake a comprehensive quantification of meridional energy transports by TCs to serve as a foundation for establishing the climate role of TCs. He will test the hypothesis that Northern Hemisphere TCs constitute a significant portion of global atmospheric dry static energy (DSE) transports from the Northern Hemisphere to the Southern Hemisphere during boreal summer and fall due to the upper tropospheric equator ward outflow jets associated with the TCs. Analyzing the composited meridional DSE transports by TCs within the Eastern North Pacific, North Atlantic, and West Pacific, the PI will determine whether the mean response is significant within each basin. Next the PI will quantify zonally integrated cross-hemispheric DSE transports at the equator by each Best-Track TC from reanalysis to determine the significance of aggregate dry static energy transports relative to the total atmosphere on time scales ranging from weeks to years. Finally the PI will examine Coupled Model Intercomparison Project (CMIP5) simulations to compare results from reanalysis to determine the fidelity of the role of TCs as evidenced in general circulation models.