FS-1996-05-03-LaRC May 1996
ERBE has helped scientists world-wide better understand how clouds and aerosols, as well as some chemical compounds in the atmosphere (so-called "greenhouse" gases), affect the Earth's daily and long-term weather (the Earth's "climate"). In addition, the ERBE data has helped scientists better understand something as simple as how the amount of energy emitted by the Earth varies from day to night. These diurnal changes are also very important aspects of our daily weather and climate.
The instruments aboard the ERBE satellites measure the amount of solar energy received by the Earth, the energy emitted by the Earth into space, and the amount of solar radiation which is reflected into space. The energy received from the sun is at short wavelengths while the energy emitted by the surface of the Earth and clouds is long wavelength radiation. Some of the shortwave radiation from the sun is reflected back into space by water vapor, ozone, clouds and small particles in the atmosphere called aerosols. Gases which absorb the longwave radiation emitted by the Earth are known as "greenhouse" gases. Increases in the amount of greenhouse gases can lead to a warming of the atmosphere, which can, in turn, cause changes in the Earth's daily and long-term weather ("climate").
For example, ERBE has provided data for investigating the significant decrease in the Earth's emitted radiation due to increased cloudiness over the equatorial Pacific Ocean during El Nino events, which occur when the ocean becomes considerably warmer than normal. The ERBE results are very important to scientists working to improve computer models for climate and weather prediction.
Water vapor in the atmosphere also affects our daily weather and climate, though scientists are only beginning to understand how these complex mechanisms work. Water vapor acts like a greenhouse gas, absorbing outgoing longwave energy. Because water vapor also condenses to make clouds, an increase in water vapor in the atmosphere also may increase the amount of clouds in the atmosphere. Using the ERBE data, scientists have begun to understand the effects of water vapor and how its variability affects clouds and ultimately, the energy balance of the Earth.
The Clouds and the Earth's Radiant Energy System (CERES), based on the highly successful ERBE, is currently being developed. CERES will extend the important ERBE measurements to include the top of the atmosphere, in the atmosphere, and global surface radiation, which are critical for advancing our understanding of the Earth's total climate system and improving climate prediction models. CERES will be flown on multiple satellites starting with a launch on the Tropical Rainfall Measuring Mission in 1997, followed by a launch on the Earth Observing System (EOS)-AM satellite in 1998 and the EOS-PM satellite in 2000.
For more information, check out the ERBE Homepage!