||Atmospheric aerosols, or fine particles, are one of the greatest sources of uncertainty in the interpretation and prediction of global climate change. Natural variations of aerosols, especially due to episodic eruptions of large volcanos, are recognized as a significant climate forcing, that is, a factor that alters the planetary radiation balance and thus may cause a global temperature change. In addition, aerosols from soil dust, biomass burning, and fossil fuel use are altering the amount and geographic distribution of atmospheric aerosols, and thus possibly affecting climate. The Global Aerosol Climatology Project (GACP) is concerned with the climate forcing due to changing aerosols, including both the direct radiative forcing by the aerosols and the indirect radiative forcing caused by effects of changing aerosols on cloud properties.
In Phase I of GACP, a 20-year global climatology will be compiled of aerosol forcing data from satellite observations and field observations for use in climate models. To accomplish this, the Earth Science Enterprise (formerly called Mission to Planet Earth) of NASA Headquarters, has issued a research announcement (NRA-97-MTPE-16). Principal investigators of the successful proposals will be included in the GACP Aerosol Radiative Forcing Science Team. This team will provide scientific guidance for a strategic approach toward definition of radiative forcing, encourage appropriate collaboration among research groups, and provide guidance to GACP. Phase II will consist of complementary field studies.
NASA and NOAA