Abstract
A method is examined for estimating the intensity of western North Pacific tropical cyclones from satellite passive microwave observations. Vertical profiles of atmospheric temperature derived from radiances remotely sensed by the Microwave Sounding Unit (MSU) onboard the current NOAA series of polar orbiting satellites are used to depict upper-tiopospheric warm anomalies associated with these storms. Data from a large sample of western North Pacific tropical cyclones are used to develop a nonlinear statistical relationship between the satellite-depicted warm core anomalies and the surface intensifies as measured by reconnaissance aircraft. Results based on an 82-case dependent sample indicate standard errors of 13 mb and 15 kt for estimates of the surface pressure anomalies and maximum wind speeds. These errors are reduced considerably when a bias in the sample intensity distribution is taken into account. Comparisons of results and method accuracy are made with a previous study of North Atlantic tropical cyclones.