Weather Forecasting Getting More Complex
August 24, 2005 1:56 PM EDT
WASHINGTON - The outlook for predicting the weather is improving. Beginning this month the complex computer programs used by forecasters are getting more data on temperatures, water vapor and gases in the air and on how the ground affects the weather, the National Oceanic and Atmospheric Administration said Wednesday.
"This advancement makes it possible for NOAA forecasters to produce more skillful forecasts," said National Weather Service director David L. Johnson. "When the GFS improves, nearly all of the National Weather Service's operational forecasts improve."
GFS is the Global Forecast System, which is used to develop a variety of forecasts up to 15 days in advance including hurricanes, heavy rain, drought, snowstorms, icing and aviation outlooks. It forecasts wind, temperature, humidity and air pressure from the ground up to 35 miles above the Earth.
NOAA said the program now includes a better look at the physics of the atmosphere, a clearer representation of the Earth's terrain and improved satellite data as well as other technical changes.
"Our nation will have longer-ranging alerts and forecasts through these improvements to the current system," said Conrad C. Lautenbacher, NOAA administrator.
Among the improvements was adding data from NASA's Atmospheric Infrared Sounder aboard the Aqua satellite.
With the improved forecast system the scientists say they expect a 12 percent to 15 percent reduction in hurricane track forecast errors at 24 through 36 hours and about a 20 percent reduction in track forecast errors at four to five days.
Stephen Lord, director of the NOAA Environmental Modeling Center, said a significant part of the change is an increase in the resolution of the GFS.
The computer model can now look at areas as small as 22 miles across, down from 35 miles previously.
