The U.S. government’s spending on weather-prediction work is often called into question by taxpayers who note that they receive all of the forecasts they need from television, radio or the Internet. But, of course, without the work of the National Oceanic and Atmospheric Administration (NOAA), few of those forecasts would be possible.

Weather forecasts — and information about numerous other areas that affect the daily lives and jobs of people around the world — are heavily dependent on data from NOAA’s weather satellites, which are operated by the agency’s National Environmental Satellite, Data, and Information Service (NESDIS).

NESDIS was created in 1982 by the merger of two organizations that today still make up its name, the National Environmental Satellite Service and the Environmental Data and Information Service.

NESDIS operates three satellite systems today. Two of those systems belong to NOAA: the Polar Orbiting Environmental Satellites, which a NOAA fact sheet says are used for long-term weather forecasts, and the Geostationary Operational Environmental Satellites, which the fact sheet says are for near-term forecasts.

NESDIS also was given responsibility in 1998 for operating the U.S. Air Force’s Defense Meteorological Satellite System constellation as an initial step towards merging that constellation with NOAA’s polar fleet.

The National Weather Service, which serves as the United States’ primary source for weather data and forecasts, is the main customer for NOAA’s satellite data.

The National Weather Service’s forecasts begin with the National Centers for Environmental Prediction, which are headquartered in Camp Springs, Md.

Satellite observations serve as the “backbone” for the global network of sensors that feed those forecasts, according to Louis Uccellini, director of the National Centers for Environmental Prediction. The centers rely on data from NOAA’s satellite fleet, as well as data from experimental satellites that are handled by NESDIS, he said in a March 15 interview.

In addition to using data from NOAA’s satellites, the National Centers for Environmental Prediction work with NESDIS to provide models that help calibrate the agency’s satellite instruments, Uccellini said.

The National Centers for Environmental Prediction include the following units: Aviation Weather, Climate Prediction, Environmental Monitoring, Hydrometeorological Modeling, Tropical Predictions, Storm Predictions, Space Environment and Central Operations.

“Center by center, they all are very heavy uses of satellite data,” Uccellini said.

For example, the Space Environment Center uses data from satellites including observations gathered about the Sun that could result in solar storms, Uccellini said.

Those predictions can be valuable both in space and on Earth. Satellite operators can use a solar storm forecast to shut down a spacecraft to avoid damage, while officials on Earth might use the same warning to take mitigating steps to prevent a disruption to electrical power grids, or inform aircraft flying over the polar regions to take alternate routes, Uccellini said.

The National Centers for Environmental Prediction will be moving their headquarters from Camp Springs to College Park, Md., in late 2007. NOAA broke ground on the new building, which also will house several NESDIS research offices currently located in Camp Springs, on March 13.

The NESDIS work on the polar and geostationary satellites will continue into the foreseeable future, as NOAA is preparing to launch the first in a new series of Geostationary Operational Environmental Satellites built by Boeing Satellite Systems of El Segundo, Calif. That launch has been delayed for several months in part due to the recently settled strike of Boeing machinists who support the company’s launch operations.

The current Geostationary Operational Environmental Satellites that are in orbit today were built by Space Systems/Loral of Palo Alto, Calif. Those satellites provide data for warnings of severe weather conditions like thunderstorms, flash floods and hurricanes, according to the NOAA fact sheet.

NOAA also plans to launch another generation of Geostationary Operational Environmental Satellites around 2012.

The Polar Orbiting Environmental Satellites and the Defense Meteorological Satellite System, which are both built by Lockheed Martin Space Systems of Sunnyvale, Calif., are scheduled to be replaced by a single constellation called the National Polar-orbiting Operational Environmental Satellite System at some point in the next decade.

The polar-orbiting satellites provide information including cloud data and temperature profiles, and monitor ozone levels as well, according to the NOAA fact sheet.

NOAA and the Air Force share funding for the new generation of polar-orbiting weather satellites, which are being built by Northrop Grumman Space Technology of Redondo Beach, Calif. That effort has run into significant technical difficulty and is currently undergoing a Pentagon review that could lead to a significant restructuring or cancellation of the program.

The National Polar-orbiting Operational Environmental Satellites were expected at one point to launch beginning in 2008, but the technical problems could push the first launch into 2012 or later.

In addition to working directly with satellites, NESDIS also assembles data collected by a variety of U.S. and international sources to make predictions on a variety of conditions on the air, ground, oceans and Sun, according to the NOAA fact sheet. This work is handled at three NESDIS data centers that archive the information to help scientists better understand the long-term trends in those areas.

Those NESDIS facilities include the National Climatic Data Center in Asheville, N.C., which maintains the world’s largest active archive of atmospheric and climate data that is used regularly by customers such as the U.S. Coast Guard and Federal Aviation Administration, according to the fact sheet.

The facilities also include the National Oceanographic Data Center in Silver Spring, Md., and the National Geophysical Data Center in Boulder, Colo.