Tropical Cyclone Asymmetries as Revealed by Recent Satellite Microwave Brightness Temperatures
Abstract
Microwave data from the Special Sensor Microwave Imager (SSM/I) were obtained for twenty-nine map times of tropical cyclones from the Northwest Pacific and North Indian Ocean. Automated analysis of 85 GHz vertical polarization (85V GHz) Brightness Temperatures (TB's) were conducted by calculating statistics at various radii from a cyclone center. These statistics were correlated against storm traits such as intensity, vortex translation speed, central pressure changes, and direction of vortex movement. The aim of this research was to determine relationships between 85V GHz data and cyclone characteristics, which could lead to the development of forecasting tools using SSM/I data. Anomalies in the 85V GHz TB fields demonstrated strong correlations to cyclone intensification by highlighting the positions and orientations of the principal rain bands. Such anomalies reveal asymmetries of convection associated with spiraling rainbands and convective eyewalls. This research demonstrated that SSM/I derived TB fields can show patterns of high correlations in the anomalies, as well as portray processes associated with intensification that occur in a tropical cyclone. Since these results were achieved through automatic methods, it is possible to develop forecast nomograms that link SSM/I TB data to cyclone traits. Such tools would be useful in the prediction of tropical cyclones.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1991
- Accession Number
- ADA249873
Entities
People
- Jeffrey H. Mccoy
Organizations
- Air Force Institute of Technology