Rainfall is a fundamental process within the Earth's hydrological cycle because it represents a principal forcing term in surface water budgets, while its energetics corollary, latent heating, is the principal source of atmospheric diabatic heating well into the middle latitudes. Latent heat production itself is a consequence of phase changes between the vapor, liquid, and frozen states of water. The properties of the vertical distribution of latent heat release modulate large-scale meridional and zonal circulations within the Tropics, as well as modify the energetic efficiencies of midlatitude weather systems.
This paper highlights the retrieval of latent heating from satellite measurements generated by the Tropical Rainfall Measuring Mission (TRMM) satellite observatory, which was launched in November 1997 as a joint American–Japanese space endeavor. Since then, TRMM measurements have been providing credible four-dimensional accounts of rainfall over the global Tropics and subtropics, information that can be used to estimate the space–time structure of latent heating across the Earth's low latitudes.
A set of algorithm methodologies for estimating latent heating based on precipitation-rate profile retrievals obtained from TRMM measurements has been under continuous development since the advent of the mission s research program. These algorithms are briefly described, followed by a discussion of the latent heating products that they generate. The paper then provides an overview of how TRMM-derived latent heating information is currently being used in conjunction with global weather and climate models, concluding with remarks intended to stimulate further research on latent heating retrieval from satellites.
Laboratory for Atmospheres, NASA Goddard Space Flight Center, Greenbelt, Maryland
NASA Jet Propulsion Laboratory-California Institute of Technology, Pasadena, California
National Institute of Information and Communications Technology, Tokyo, Japan
NASA Headquarters, Washington, DC
Department of Meteorology, The Florida State University, Tallahassee, Florida
Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado
Science Systems and Applications, Inc., Greenbelt, Maryland
Hydrospheric Atmospheric Research Center, Nagoya University, Nagoya, Japan
Japan Meteorological Agency, Meteorological Research Institute, Tsukuba, Japan
Department of Aerospace Engineering, Osaka Prefecture University, Sakai, Osaka, Japan
UMBC Joint Center for Earth Systems Technology, Baltimore, Maryland
Center for Climate System Research, University of Tokyo, Tokyo, Japan
Department of Atmospheric and Oceanic Sciences, University of Wisconsin—Madison, Madison, Wisconsin
School of Computational Sciences, George Mason University, Fairfax, Virginia