Mesoscale features from TOPEX sea surface height data

Abstract

Satellite altimetry has been used in vanous studies to gain a better understanding of the world's oceans. These studies have varied from global circulation to studies on mesoscale activity. In the past, satellite altimeter measurements of sea surface height have been plagued by large orbit errors and primitive gravity models. TOPEX/POSEIDON was launched on August 10, 1992 and has been providing near real-time, accurate sea surface height data to the scientific community since its launch. The accuracy of the TOPEX/POSEIDON orbit is much better than initial expectations achieving an RMS error of ~ 3 em. The geoid error is still the dominant error source and prevents studies of time independent ocean circulation with wavelengths less than 1000 km. With careful removal of the geoid error, time-dependent mesoscale ocean circulation can be studied. This study is divided into three main sections. The first part deals with the general oceanography of the north central Pacific Ocean and the Emperor Seamount Chain. The second part deals with the TOPEX/POSEIDON satellite and the errors associated with this mission. The third section deals with time-dependent mesoscale features that were found using the TOPEX sea surface height data. A comparison with previous studies which support the existence of these features is presented.