RELEASE NO: 98-208

New Earth Science discoveries by Goddard Space Flight Center scientists will be reported at the 1998 American Geophysical Union fall meeting in San Francisco this week. Goddard researchers offer unique insights on topics ranging from Climatic Effects of the Changing Sun, Mars Exploration, El Nino, Earth’s Topography and the Effects of Large Fires. Time and place of the presentations are indicated with each entry.

SOLAR VARIABILITY AND CLIMATE CHANGE

Stratospheric ozone and circulation amplify small changes in solar irradiance during the 11 year solar cycle, according to a new climate model, suggesting indirect effects of a changing Sun on climate may be more significant that previously supposed. Dr. Drew Shindell reports his findings on Sunday, Dec. 6 at 10:20 am in Rm 133.

PREDICTING THUNDERSTORMS

The effects of soil moisture and wind on thunderstorm development were studied in Florida- the U.S. state with the highest number of thunderstorms. The study will provide a better understanding of thunderstorms and could lead to improved thunderstorm prediction. Dr. R. David Baker presents the results of his findings in a poster session on Sunday, Dec. 6 at 1:30 in Hall D.

TOPOLOGY OF POLAR REGION IMPACT CRATERS ON MARS

A broad variety of impact craters, ranging in size from approximately two to 150 kilometers were observed by the Mars Orbiting Laser Altimeter (MOLA) sensor on the Mars Global Surveyor. Dr. James Garvin reports the latest MOLA findings on Sunday, Dec. 6 at 1:45 in Rm 307.

EL NINO - A VIEW FROM SPACE The 1997-1998 "El Nino Event of the Century" has been the best monitored El Nino on record. The 1997-1998 El Nino and subsequent La Nina will have been observed from start to finish. Dr. Antonio Busalacchi reports the results of his findings in a talk on Monday, Dec. 7 at 8:45 a.m. in Rm 134.

LASER ALTIMETRY USED TO EVALUATE THE EARTH’S TOPOGRAPHY

For the first time a laser altimeter in space was used to evaluate our knowledge of the Earth’s topography. Measurements from the Shuttle Laser Altimeter show that the best publicly available global topographic dataset has regional errors in elevation as large as 10's of meters. These biases may seem small, but are significant for applications involving changes in the Earth's topography over time. Dr. David Harding reports the results on Monday, December 7 at 1:30 in Rm 303.

LA NINA SHORTENS THE DAY

At the peak of El Nino, the length of day increased. As predicted at the 1998 Spring AGU, this increase has been followed by an abrupt decrease in the length of day. Thomas A. Clark presents these findings in a poster session on Monday, December 7 at 3:30 in Hall D.

LASERS IN EARTH AND PLANETARY EXPLORATION

For over 3 decades, lasers have been a valuable tool of the world’s space programs for accomplishing a variety of engineering and scientific objectives. Dr. David E. Smith presents the Bowie Lecture on "Lasers in Earth and Planetary Exploration" on Monday, December 7 at 3:45 p.m. in Rm 303.

IMPACT OF EL NINO ON REGIONAL HYDROLOGY

El Nino brought with it a range of severe local and regional droughts, storms and floods. It is well known that El Nino/La Nina changed the continental weather patterns considerably, however the connection to local and regional hydrological phenomena needs to be made. Satellite observations and analysis data are used to establish a relation between local hydrology and large scale weather patterns. Venkataraman Lakshmi presents the results of his findings on Tuesday, Dec 8 at 3:35 in Rm 300.

UPLIFTING SOUTHERN ALASKA MOUNTAINS

Ten GPS stations in southern Alaska have been used to estimate how fast the mountains are rising. The new measurements have been compared to the long-term expression of uplift seen in the topography of the region. Jeanne Sauber represents the results of her findings on Tuesday, Dec. 8 at 4:35 in Rm 133.

MONITORING OCEANIC ISLANDS

RADARSAT has been used to monitor the landscape of 20 oceanic islands, including islands that extend from the Arctic, throughout the Atlantic and Southern Indian oceans and into the equatorial Pacific. Dr. Jim Garvin is presiding over the special union session, Oceanic Islands and Global Environmental Change, on Wednesday, Dec. 9 at 8:40 in Rm 303. Dr. Garvin’s talk during this session will begin at 11:30.

MONITORING CARBON DIOXIDE FROM BIOMASS BURNING

By using the Earth Observing Satellite, Goddard scientists can monitor carbon dioxide from biomass burning all over the Earth every day. Andrew Wald presents the results of his findings in a poster session on Thursday, Dec. 10 at 1:30 in Hall D.

ATMOSPHERIC EFFECTS OF LARGE FIRES

A new technique for studying tropical tropospheric ozone has made real-time ozone maps available for the first time. Videos will be shown of tropospheric ozone produced from fires in the tropics. Dr. Anne Thompson presents the results of her findings in a poster session on Thursday, Dec. 10 at 1:30 in Hall D.

Editors Note: If you would like to interview Goddard scientists about these projects, contact Lynn Chandler in the AGU newsroom (415) 905-1007 or page her at the number listed above.