An Ocean Science Revolution: 23 Years of Precision Altimetry

Abstract:

The world’s Oceans cover more than two-thirds of the Earth’s surface, so measurements of their shape and height play a key role in the advancement of geodesy. In 1992 NASA and CNES launched TOPEX/Poseidon to measure the global oceans on a 10-day repeat with an accuracy of just a few centimeters. Referred to as the most successful oceanographic experiment of all time, TOPEX and its successors Jason-1 and Jason-2 revolutionized the field of oceanography. Satellite altimeters are now used routinely to chart and predict ocean currents, track global and regional climate phenomena such as El Nino, predict hurricane intensity and even to estimate the shape and depth of the sea floor. But one of the greatest accomplishments of satellite altimetry is the unbroken, 23-year record of global and regional sea level change. No other climate record provides a more direct and far reaching measure of Earth’s changing climate. As satellite altimetry evolves, it will continue to provide key information about the oceans and climate, but it will also provide information on increasingly smaller scales. This paper will cover these and other major advances and discoveries made possible by satellite altimetry, and discuss the roadmap for the future.