PUBLIC INFORMATION OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIFORNIA 91109. TELEPHONE (818) 354-5011
http://www.jpl.nasa.gov

Contact: Mary Hardin, JPL, (818) 354-5011
Phillipe Collot, Centre National d'Etudes Spatiales
(CNES), Paris (Phone: 33-1-44-76-78-04)

NOTE TO EDITORS:October 8, 1997

NASA AND FRENCH SPACE AGENCY SPONSOR SPACE OCEANOGRAPHY CONFERENCE

      Oceanographic experts from around the world will meet Oct. 15-17 in Biarritz, France, to discuss the emerging prospects for an integrated approach to ocean science that combines space observations, in-situ measurements and numerical models in new ways that could lead to months-long forecasts of ocean dynamics on regional and global scales.

      The symposium, titled "Ocean Monitoring to the Year 2000: An Integrated Approach," will focus on a variety of scientific results flowing from the U.S.-French TOPEX/Poseidon satellite, launched in 1992, and plans for its smaller, yet equally capable successor, Jason-1, due for launch in May 2000.

      "TOPEX/Poseidon has been a blueprint for productive international Earth science cooperation, and the findings of this symposium should lay the groundwork for Jason-1 to extend this cooperation through at least the early years of the 21st century," said William Townsend, Acting Associate Administrator for the NASA Office of Mission to Planet Earth, Washington, DC.

      TOPEX/Poseidon, a joint program of NASA and the Centre National d'Etudes Spatiales (CNES), the French space agency, uses a radar altimeter to precisely measure sea-surface height. Scientists use the data from TOPEX/Poseidon to produce global maps of ocean topography every ten days. The satellite has mapped this circulation with an absolute accuracy of four centimeter (1.8 inches), versus its design goal of 13 centimeter (5.9 inches).

      A major focus of current TOPEX/Poseidon research is the monitoring of the third weather-disrupting phenomenon known as El Niño that has been observed during the satellite's lifetime. An El Niño is thought to be triggered when steady westward blowing trade winds weaken and even reverse direction. This change in the winds allows the large mass of warm water that is normally located near Australia to move eastward along the equator until it reaches the coast of South America. This displaced pool of unusually warm water affects evaporation, where rain clouds form and, consequently, alters the typical atmospheric jet stream patterns around the world.

      TOPEX/Poseidon sea-surface height data are essential to a better understanding of the role oceans play in regulating global climate change, one of the least understood areas of climate research. TOPEX/Poseidon is part of NASA's Mission to Planet Earth, a coordinated, long-term research program to study the Earth as a global system.

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