Assimilation of GPS radio occultation data for Tropical Cyclogenesis: A Case Study in the Eastern Atlantic Ocean

This study is aimed to investigate the impact of using Global Positioning System Radio Occultation (GPS RO) sounding data (i.e., Constellation Observing System for Meteorology, Ionosphere, and Climate; COSMIC) for tropical cyclogenesis (TC-genesis) research. The Weather Research and Forecasting (WRF-ARW) model and the WRF data assimilation system (i.e., WRF 3DVAR) were employed to simulate tropical depression- 8 (TD8) 2006. A noteworthy feature about TD8-genesis was that Saharan dust outbreak was also observed during this period, which made this event more sophisticated. The time frame to be focused on is from 1200 UTC September 09 to 1200 UTC September 12, 2006. The level 2 wetPrf COSMIC data is adopted in this research. A 72-hour integration is performed initial and time dependent lateral boundary conditions were derived from the NCEP final analysis data (FNL). A 2-domain nested simulation is configured with 30 km, and10 km horizontal resolutions, respectively. Simulation results from all the experiments performed with different RO soundings combination shown that the RO sounding 8 has the greatest significant impact on TD8 simulation. Elevation, time, and location are the parameters that made RO sounding 8 the most treasured sounding to analyze TD8.