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NASA'S EARTH SCIENCE HIGHLIGHTS FOR 1999 FALL MEETING - AGU

New Earth science insights by Goddard Space Flight Center (Greenbelt, Md.) scientists will be reported at the 1999 American Geophysical Union fall meeting in San Francisco this week. Listed below are some of the discussions that are opened to the news media. All discussions will be held in the Moscone Convention Center in San Francisco.

A New Ozonesonde Data Set for the Earth Science Community - In the past several years, new tropical tropospheric ozone data products have been developed from Total Ozone Mapping Spectrometer and other spacecraft. A two-year project collected weekly ozonesonde measurements at southern hemispheric tropical sites and this data is now being made available. Dr. Anne Thompson shares her results in a poster session on Tuesday, Dec. 14 at 1:30 p.m. in Hall D.

Glaciers and Ice Sheets - Recent changes have occurred in ice streams in the West Antarctic. The debate continues whether the grounding line has advanced or retreated. Dr. Robert Bindschadler will present his latest findings on Tuesday, Dec. 14 at 2:15 p.m. in Room 306.

The Latest from Mars III - More than 2,000 impact features have been topographically characterized by the Mars Orbiter Laser Altimeter (MOLA) flying on the Mars Global Surveyor spacecraft. Many of these impact craters can now be rendered in digital elevation models from multiple profiles and all of the geometrical properties of these landforms have been measured. Dr. James Garvin presents the latest results on Tuesday, Dec. 14 at 4:15 in Room 102.

Evidence of Many Buried Impact Basins on Mars - Mars Orbiter Laser Altimeter data provide convincing evidence for a large number of buried or mantled impact basins on Mars. Dr. Herb Frey reports the latest from the Mars Orbiter Laser Altimeter sensor in a poster session on Wednesday, Dec. 15 at 1:30 in Hall D.

First Look at Landsat 7 Mission Performance - Landsat are the United States' oldest land-surface observation satellites. Landsat 7 builds on a 27-year continuous archive of images of the Earth. Since Landsat 7 was launched in April, over 50,000 images have been acquired and archived. Dr. Darrel Williams will present his latest findings on Thursday, Dec. 16, at 9:20 a.m. in Room 135

Assessing Tropical Landscape in Braulio Carillo National Park, Costa Rica
Using state-of-the-art laser remote sensing technology, the vertical and horizontal structure of a complex and dense tropical forest was measured on a large scale for the first time. Over 193 square miles (500 square kilometers) of forests in Costa Rica were mapped. Dr. Robert Knox will present the results on Thursday, Dec. 16 at 3:00 p.m. in Room 307.

The Geoscience Laser Altimeter System (GLAS) for the ICESAT Mission - The instrument design and expected performance of the next generation space lidar being developed will be presented by Dr. James Abshire on Thursday, Dec. 16 at 3:50 in Room 307.

Modeling Surface Structure Derived From Laser Altimeter Return Waveforms Using High-Resolution Elevation Data - The upcoming generation of NASA's spaceborne laser altimeters (e.g. Vegetation Canopy Lidar and GLAS) record the interaction of a short laser pulse with the Earth's surface. These return signals contain vast amounts of information about topography and vegetation. Modeling these returns helps bridge the gap between the data collected by these unique instruments and their science applications. Bryan Blair will present how this is performed on Thursday, Dec. 16 at 4:05 p.m. in Room 307.

Analysis and Use of Water Quality - The Chesapeake Bay is the United States' biggest and most productive estuary. The water quality of the Chesapeake Bay has been assessed using Landsat's Thematic Mapper and SeaWifs satellite data. David Toll will present his findings on Friday, Dec. 17 at 1:30 in a poster session in Hall D.