May 13, 1996


Teams of high school and junior high students will launch buoys into Galveston Bay, Texas to calibrate altimeter measurements from the TOPEX/Poseidon satellite in an experiment that will helpoceanographers better understand ocean dynamics and calculate global sea level rise.

The NASA/JPL-sponsored buoy "float-off" will take place at 10 a.m. Central Time, Wednesday, May 15 in Galveston Bay, near Eagle Point, Texas.

Each team of students has designed and built their own buoy and each buoy is equipped with a Global Positioning System (GPS) receiver. The buoys will record sea level and wave height measurements along the satellite groundtrack as TOPEX/Poseidon flies overhead. This information will be used in conjunction with data from several tide gauges in the area to validate the satellite's performance.

"It's crucial that we have continuing calibration of the satellite's altimeter height measurements to help us determine if the global sea level is rising," said Dr. George Born, a TOPEX/Poseidon science team member at the University of Colorado, Boulder. "Locally, the measurements of sea level in Galveston Bay by the altimeter will prove useful in improving tide models by providing a reality check."

"Galveston Bay is an ideal site for us to conduct this experiment. The TOPEX/Poseidon satellite passes directly over the center of the Bay, there are numerous tide gauges to further verifythe measurements and relatively low waves," said Amy Neuenschwander of the University of Texas Center for Space Research (UTCSR). "This Bay is one of Texas' most important coastal environment, containing natural resources which are self-renewing as long as the bay remains healthyand productive."

"Improved tide and circulation models will improve the ability to track pollutants such as oil spills in the Bay as well as improving biological models. Hence, the experiment has the long term potential to provide a modest contribution to maintaining a healthy ecosystem in the Bay," Born explained.

The "float-off" is part of an on-going educational outreach program between JPL, UTCSR, Texas Space Grant Consortium (TSGC) in conjunction with the Colorado Center for Astrodynamics Research(CCAR), and the Colorado Space Grant Consortium (CSGC). The Texas students are from two Houston area high schools, Friendswood and Pearland, and one middle school, Seabrook Intermediate. The Colorado students are from Boulder High School and the University of Colorado.

TOPEX/Poseidon, a joint program of NASA and the Centre National d'Etudes Spatiales, the French space agency, uses a radar altimeter to precisely measure sea-surface height. Launched in August 1992, the satellite measures the sea surface with an unprecedented accuracy of less than 5 centimeters.

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. TOPEX/Poseidon's sea-surface height data are essential to a better understanding of the role oceans play in regulating global climate, one of the least understood areas of climate research.

The Jet Propulsion Laboratory manages the U.S. portion of the TOPEX/Poseidon mission for NASA.


Last Modified: Fri, Aug 20, 1998