Objective Analysis of Tropical Cyclone Location and Motion from High-Density Observations

Abstract

A new technique for objectively locating the pressure center of a hurricane from high-density observations is presented. It was designed particularly for use with global positioning system (GPS) dropsonde observations of pressure within the cyclone core, but is also useful for aircraft data. Unlike previously documented techniques, it uses pressure data rather than wind, and is therefore useable in the boundary layer. A further advantage is that it can utilize data taken over a period of several hours, while previous techniques required the use of nearly instantaneous data. It is shown that, for data coverage typical of research aircraft missions, the technique can locate the cyclone center with a root-mean-square error of a few kilometers, and the cyclone motion with a root-mean-square error of a few tenths of a meter per second. The application of an automated objective quality control procedure to the method is also discussed.