The Open Atmospheric Science Journal

2018, 12 : 33-47
Published online 2018 April 30. DOI: 10.2174/1874282301812010033
Publisher ID: TOASCJ-12-33

RESEARCH ARTICLE
Assimilation of GPS Radio Occultation Data for Tropical Cyclogenesis: A Case Study in the Eastern Atlantic

Keren Rosado1, * and Sen Chiao2
1 Department of Atmospheric Science, Howard University, Washington, DC, USA
2 Department of Meteorology and Climate Science, San Jose State University, San Jose CA, USA

* Address correspondence to this author at the Department of Atmospheric Science, Howard University, NOAA/ESRL 325 Broadway Boulder, CO 80305-3337, Washington, DC, USA; Tel: (303) 497-5907; E-mail: keren.rosado@howard.edu

ABSTRACT

Aim:

This study 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.

Methods:

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 was from 1200 UTC September 09 to 1200 UTC September 12, 2006. The level 2 wetPrf COSMIC data was adopted in this research. A 72-hour integration wasperformed with initial and time-dependent lateral boundary conditions derived from the NCEP final analysis data (FNL). A 2-domain nested simulation was configured with 30 km, and10 km horizontal resolutions, respectively.

Results:

Simulation results from all the experiments performed with different RO soundings combination showed that the RO sounding 8 has the greatest significant impact on TD8 simulation.

Conclusion:

Elevation, time, and location are the parameters that made RO sounding 8 the most treasured sounding to analyze TD8.

Keywords:

Tropical Cyclogenesis Research, TD8-genesis, Saharan dust outbreak, RO soundings, TD8 stimulation, COSMIC.