Assimilating MODIS Aerosol Optical Depth using WRF-Chem on Tropical Cyclogenesis

This study is aimed to advance our understanding of the impact of the Saharan air layer (SAL) over tropical cyclogenesis. Two developed cases (Hurricanes Helene 2006 and Julia 2010) and two non-developed cases from the 2011 and 2012 hurricane season, respectively, are investigated using the Weather Research and Forecasting model (WRF). It is our intention to isolate key characteristics that define the formation stage of tropical cyclones.

Furthermore, this study will be conducted involving aerosols schemes from the WRF Chem model. The Goddard Chemistry Aerosol Radiation Transport (GOCART) and Model for Simulating Aerosol Interactions and Chemistry (MOSAIC) will be utilized to recreate the environmental conditions and the impact of the variation of the parameters on TC-genesis. The primary interest in using the GOCART aerosol scheme is that the model can simulate dust concentration and meteorological fields over West Africa and the adjacent eastern tropical Atlantic Ocean. The Gridpoint Statistical Interpolation (GSI) Data Assimilation System will be applied to assimilate MODIS aerosol optical depth in simulating TC-genesis. The ultimate goal is to quantify the interactions of the SAL on TC-genesis as well as non-developed systems over eastern Atlantic Ocean basin.