The Effects of Gap Wind Induced Vorticity on Tropical Cyclogenesis

The circumstance under which a Tropical Cyclone forms is still a highly debated and not well understood topic within meteorology. It has been suggested that most of the Tropical Cyclones formed in the Eastern Pacific Basin originated from Tropical Disturbances formed in the Atlantic Ocean. In this model, some of the disturbances that did not form in the Atlantic propagate into the Pacific. This study aims to determine how vorticity generated by winds passing through the Central American Mountains influences the development of tropical cyclones in the Eastern Pacific basin and how this mechanism contributes to the previously discussed model. A technique for calculating scatterometer derived area-averaged vorticity is applied to QuikSCAT wind data. This is then combined with GridSAT IR imagery to track the disturbances in order to determine how the vorticity created by gap winds influences tropical cyclogenesis. It is found that positive relative vorticity generated in association with gap wind events through the Central American Mountains contributes to the formation of Tropical Cyclones in the Eastern Pacific.