Examination of the tropical cyclone environment through comparison of COSMIC with other satellite data

Measurements of GPS signal refractivity observed by Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) satellites are used to examine the vertical distribution of moisture in the vicinity of tropical cyclones. COSMIC can detect moisture with high accuracy and high vertical resolution, which is ideal for detecting vertical layers of moisture, particularly the depth of a Saharan Air Layer (SAL), which consists of both dry air and Saharan Desert dust.

SAL detection by COSMIC data is validated in horizontal space against the split-band (12.0μm minus 10.8μm) product of METEOSAT, and in vertical space with the aerosol profiles of the NASA CALIPSO satellite. Results for Atlantic tropical cyclones of 2006, 2007, and 2008 are to be presented.

As GPS radio signals can pass through thick cloud cover and precipitation, the COSMIC data can be beneficial to the analysis of the internal structure of tropical cyclones typically obscured by the cirrus overcast. The slanted nature of a COSMIC profile can allow for examination of the mesoscale features of a tropical cyclone in both vertical and horizontal space. Evidence of COSMIC detection of eyewall and rainband structure in recent tropical cyclones will be presented.