Sunday, 22 January 2012
Numerical Studies of Convective Initiation in Barbados
Hall E (New Orleans Convention Center )
This study investigates the convective event of 26 August 2006 that occurred in Barbados. Barbados is located at 59°32 W, 13°10 N. The island is approximately 430 km2 in size with the highest point at 336 m above sea level. To the east of Barbados, the nearest land mass is the Canary Islands and the African coastline, approximately 4000 km away. Localized convection in Barbados normally account for a significant percentage of the annual rainfall, however these features are difficult to capture due to their small temporal and spatial scales. Yet, additional observations are generally limited and sparse. The mechanisms that allow for this formation is not understood thus forecasting the phenomenon is quite difficult. The working hypothesis, which has been previously disregarded by previous observers and researchers, is that the topographic effect plays a major role of initiating island scale convection as well as enhancing precipitation over Barbados. Through numerical simulations the mechanisms for formation are examined. It was found that the boundary-layer convergence zone of the sea-breeze front is not the only factor, or most significant, but rather the topography of the island as well as local surface circulations.