ONE- TO TWO-MONTH OSCILLATIONS IN SSMI SURFACE WIND SPEED

M. L. Collins and J. L. Stanford, Department of Physics and Astronomy, Iowa State University, Ames, IA 50011

D. Halpern, Earth and Space Sciences Division, Jet Propulsion Laboratory, California Institue of Technology, Pasadena, CA 91109

Geophys. Res. Letts., 21, 2685-2688 (1994).

Abstract

The wind speed at 10 m over the ocean can be estimated from microwave brightness temperature measurements recorded by the Special Sensor Microwave Imager (SSMI) instrument mounted on a polar-orbiting spacecraft. Four-year (1988 - 1991) time series of average daily 1o x 1o SSMI wind speeds were specrtally analysed at selected sites in the tropical western Pacific Ocean. One- to two-month period wind speed oscillations with amplitudes statistically significant at the 95% confidence level were observed near Kanton Island, Eniwetok Island, Guam, and Truk Island. This is the first report of such an oscillation in SSMI wind speeds.