April 29, 2003
Your weatherperson's job just got a little easier, thanks to new data now available from advanced weather instruments aboard NASA's Aqua satellite.
The new data are the most accurate, highest-resolution measurements ever taken from space of the infrared brightness (radiance) of Earth's atmosphere. This information can be used to make more accurate predictions of weather and climate.
The data come from microwave and infrared sounding instruments that are part of the Atmospheric Infrared Sounder experiment: the Atmospheric Infrared Sounder and the Advanced Microwave Sounding Unit.
With its visible, infrared and microwave detectors, the Atmospheric Infrared Sounder experiment provides a three-dimensional look at Earth's weather. Working in tandem, its instruments can make simultaneous observations from space all the way to Earth's surface, even in the presence of heavy clouds. With almost 2,400 channels sensing different regions of the atmosphere, the system creates a global, three-dimensional map of atmospheric temperature and humidity and provides information on clouds, greenhouse gases and many other atmospheric phenomena.
"The Atmospheric Infrared Sounder experiment is demonstrating high sensitivity and accuracy," said Dr. Moustafa Chahine, science team leader at NASA's Jet Propulsion Laboratory, Pasadena, Calif., which manages the experiment. "Meteorologists around the world have been eagerly awaiting the availability of this processed Atmospheric Infrared Sounder data, and are already reporting measurable increases in the accuracy of their short-term weather predictions. NASA and the world's weather prediction agencies can now also use Atmospheric Infrared Sounder experiment data to better track severe weather events, like hurricanes."
Scientists from various organizations echoed Chahine's views:
-- Dr. Tony McNally of the European Center for Mid-range Weather Forecasts in Reading, England, reported that the use of Atmospheric Infrared Sounder experiment data resulted in "a small but consistent positive impact on forecast quality in all areas."
-- Dr. Hank Revercomb, director of the Space Science and Engineering Center at the University of Wisconsin, called the experiment "a virtual gold mine of information."
-- Dr. Louis Ucellini, director of the National Oceanic and Atmospheric Administration's National Centers for Environmental Prediction, said adopting data from the Atmospheric Infrared Sounder experiment is "our number one priority."
Chahine said more advanced data products are expected to become available later this year. The data will include atmospheric temperature and humidity profiles as well as additional environmental measurements on various types of clouds, particularly the thin veil of cirrus clouds that cover Earth. He also expects new data on concentrations of greenhouse gases, such as carbon dioxide, methane, carbon monoxide and volcanic sulfur dioxide.
The National Oceanic and Atmospheric Administration is continuing to evaluate the new data, learning how to integrate it and gaining confidence in its accuracy. When that process is completed this summer, the agency will begin integrating the data into existing weather prediction models used by its National Centers for Environmental Prediction. Six of the world's leading weather-prediction centers will do the same. The data will also be distributed to the World Meteorological Organization in Switzerland, where it will be available to 105 countries.
Aqua's planned six-year mission will collect data, using six onboard instruments, on global temperature variations, the cycling of water, global precipitation, evaporation, changes in ocean circulation, and how clouds and surface-water processes affect climate. The information will help scientists better understand how global ecosystems change and how they respond to and affect global environmental change.
For more information, visit: http://www.jpl.nasa.gov/airs. NASA's Earth Science Enterprise is dedicated to understanding Earth as an integrated system and applying Earth system science to improve prediction of climate, weather and natural hazards using the unique vantage point of space. The California Institute of Technology in Pasadena manages JPL for NASA.
JPL/Alan Buis (818) 354-0474
NASA Headquarters, Washington, D.C.
Elvia H. Thompson (202) 358-1696