Volume 8, Number 3     May/June 2000

NASA Helps Improve Weather Prediction

NASA's role in studying planet earth is to further scientific research and technology to help forecasters make more accurate weather, climate and natural hazard predictions in the new millennium.

NASA technology and climate studies can help predict such dramatic events as El Niño and La Niña–providing advance notice that saved America billions of dollars last year alone. For the future, NASA has set goals for its Earth Sciences research and technology development projects that may result in new satellite technologies and models to help the National Weather Service replace the common three- to five-day forecasts of today with accurate ten- to fourteen-day forecasts.

With the use of satellite data and better computer modeling techniques, meteorologists in the next ten years may be able to predict El Niño weather conditions up to 15 months in advance and detect hurricanes far enough ahead to help protect lives and property, NASA Administrator Daniel Goldin recently told weather forecasters at the first annual American Meteorological Society (AMS) convention of the new millennium.

"What most people don't know is that our efforts to open the space frontier are largely based on our quest to understand our own planet," Goldin said in a keynote address to the AMS convention in Long Beach, California. "Our development of new technologies and Earth-observing spacecraft complement the vital work of our sister agencies in weather prediction and global climate modeling."

As one example, new research shows that adding rainfall data from NASA's Tropical Rainfall Measuring Mission (TRMM) satellite and other meteorological satellites to forecast models can more than triple the accuracy of short-term rainfall forecasts. These findings were also presented to the AMS by researchers at Florida State University, Tallahassee, and will be featured in an upcoming edition of the Journal of Climate.

Spaceborne technologies used to study the effects of Hurricane Floyd indicate that extensive rainfall along the North Carolina coast may have significant impacts on the marine food chain and thousands of people.

"Following Hurricane Floyd, record-breaking rains continued to soak the area, washing mountains of sediment and waste into the water system," said NASA oceanographer Gene Feldman of NASA's Goddard Space Flight Center in Greenbelt, Maryland. Now rivers and tributaries along the Atlantic Ocean are choked and major ecological changes are happening.

'Periodically, levels of dissolved oxygen in the water have dropped dramatically as organic matter decomposes, and aquatic life has been threatened in dozens of estuaries and peripheral habitats, commonly referred to as 'dead zones.' The current changes in the area may have lasting repercussions for hundreds of thousands of people,' Feldman said.

The TRMM is a NASA/Japanese mission that continues to provide profound new insights into events such as hurricanes, probing them in three dimensions to reveal how energy is distributed within the storm. This knowledge will help experts understand how these most violent of Earthbound storms work. Experimental forecasts done last fall using this satellite's data demonstrated much better tracking of some of the year's devastating East Coast hurricanes, including Dennis and Floyd.

“Making such improvements in even the short-term forecasts is important because it demonstrates that we are learning more about the behavior of rainfall within these models,” said Chris Kummerow, the spacecraft project scientist at Goddard Space Flight Center.

Landsat 7 image of the Pamlico River in North Carolina after Hurricanes Floyd and Irene in September 1999. (Photo supplied by Goddard Space Flight Center's Science Visualization Studio)

Scientists studying Hurricane Floyd's effect on algae blooms and phytoplankton, important links in the regional marine food chain, say their data will also help them understand how the hurricane's aftermath may affect the fragile environment in the coming months.

Using data from NASA's Earth-orbiting Sea-viewing Wide Field-of-view Sensor (SeaWiFS) and an airborne laser instrument, scientists from the National Oceanic and Atmospheric Administration (NOAA) can monitor algae growth over large regions, including Pamlico Sound between the North Carolina mainland and the Outer Banks.

According to Pat Tester, a NOAA scientist at the Center for Coastal Fisheries and Habitat Research in Beaufort, North Carolina, fertilizer and other nutrients that flowed down the storm-flooded rivers in eastern North Carolina are feeding the algae or phytoplankton in the sounds.

"One question is what happens to the aquatic activity in the sounds when this algae dies and begins to starve the waters of oxygen," Tester said. "The long-term observations provided by the NASA technology will help us monitor the phytoplankton in the water."

"The NASA technology improves our ability to monitor these important fishery areas by covering larger areas than direct sampling from boats can, and by providing this information for weeks or months," Tester said.

Additional ongoing Earth Science missions that contribute to our understanding of the global climate include:

• Landsat 7, an Earth-mapping satellite that provides imagery of the planet for use in understanding natural events all over the world. Building on a 27-year heritage of data, Landsat 7 can help researchers understand the effects of hurricanes and floods, as well as monitor large-scale fires and droughts all over our planet.

• QuikSCAT, a satellite launched last year that tracks wind currents over the ocean's surface. This information helps scientists understand the interactions between Earth's oceans and the atmosphere, and is being used by NOAA to improve marine weather forecasts.

• TOPEX/Poseidon, a NASA/French mission that uses radar to study ocean-surface topography and heat content, two more clues into how El Niño and other ocean events affect the weather that crosses our nation each day.

• The ACRIMSAT mission, launched last December, will measure how changes in the Sun's energy affect Earth's climate.

• Terra, also launched last December, will enable new research into the ways that Earth's lands, oceans, air, ice and life function as a planet-wide system. In the coming months and years, this major "Earth Observatory" will provide new insights into how our home planet behaves.

NASA's Earth Science Enterprise at NASA Headquarters in Washington, DC is a long-term research enterprise designed to study the Earth's land, oceans, air, ice and life as a total system.

North Carolina flood, October 26, 1999. (Photo supplied by Goddard Space Flight Center's Science Visualization Studio)

For more information, contact David E. Steitz at NASA Headquarters, 202/358-1730 or visit http://www.earth.nasa.gov Please mention you read about it in Innovation.