RELEASE NO: 97-171

NASA’s Earth Science Program-1997 Fall AGU Tip Sheet

Goddard Space Flight Center (Greenbelt, Md.) Earth science results reported at the 1997 American Geophysical Union (AGU) fall meeting in San Francisco offer unique insights about our planet on topics ranging from El Nino, Mars Exploration, Climate Change, Greenland Ice Sheet, Volcanoes and the Global Distribution of Aerosols. Below are a few talks Goddard scientists will be giving at the AGU meeting. Time (all times are Pacific Standard time) and place of the discussions are indicated.

Goddard presents preliminary results on global climatic anomalies observed during the current 1997-98 El Nino. These anomalies include a general warming of the tropical ocean and land, cooling over the polar regions, rainfall deficit in Indonesia, and wet conditions over the east coast of Africa. Dr. Ebby Anyamba reports the results of her findings on Tuesday, Dec. 9 at 4:20 p.m. in Room 120

On Sept. 15, the Mars Orbiting Laser Altimeter was turned on to make the first altimeter observations of Mars. This short opportunity of approximately 20 minutes in length was a test and calibration of the instrument in preparation for the mapping phase of the mission that is due to begin in March 1999. Dr. David E. Smith reports the results of his findings on Tuesday, Dec. 9 at 10:45 a.m. in Room 134.

The "detection of climate change" will occur when a climate change is large enough to be noticeable to people. The Common Sense Climate Index is defined where a simple measure of the degree (if any) to which practicle climate change is occurring. The data indicate that global warming is on the verge of being detectable by the lay person. Additional data show that greenhouse gas growth rates have declined sharply in recent years, improving the chances of avoiding large undesirable climate change in the 21st century. Dr. James Hansen reports the results of his findings on Thursday, Dec. 11 at 9:10 a.m. in Room 305.

Estimates of the overall mass of the ice surface elevations were measured by satellite altimetry. Although satellite radar altimetry has significant limitations in coverage and accuracy over sloping surfaces, information on ice-sheet surface-elevation changes has been derived for parts of Greenland. Dr. H. Jay Zwally reports the results of his findings on Monday, Dec. 8 at 8:35 a.m. in Room 133.

Real time and near-real time satellite data on the presence of volcanic ash with warnings on potential hazards to aircraft using Total Ozone Mapping Spectrometer data are available to the aviation industry for the first time thanks to a joint NASA/NOAA agreements. Volcanic clouds can cause engine stoppage in flight and extensive damage to the airframe, windows, and sensors of large jet aircraft. So far, emergency landings have been successful although repairs to the aircraft have cost up to $80 million. At least 15 aircraft have been damaged in North Pacific routes alone since 1980. More than 20 others were damaged in the eruption of Mt. Pinatubo in 1991. Dr. Arlin Krueger reports the results of his findings Wednesday, Dec. 10 at 1:50 p.m. in Room 302

The Total Ozone Mapping Spectrometer is able to observe aerosols in any region not totally obscured by clouds. The frequency of occurrence of aerosol plumes, their large-scale sources, and their seasonal behavior will be discussed. Preliminary results show a strong seasonal dependence of non-absorbing aerosols over both land and water. For example, the minimum amount over the oceans occurs in mid-summer and the maximum during the winter months. Dr. Jay Herman reports the results of his findings Wednesday, Dec. 10 at 8:30 a.m. in Room 130.

If you would like to interview Goddard scientists about these projects, contact Lynn Chandler in the AGU newsroom or page her at the number listed above.