Earth Observation Mission News
NASA's SMAP map clarify link from wet soil to weather
19 November 2014
Anyone who spends time outdoors knows that weather influences soil moisture -- the moisture locked in soils that allows plants to grow -- through temperature, wind and, of course, rain and snowfall. But in our complex, interlocking Earth system, there are almost no one-way streets. How does soil moisture influence weather in return?
NASA's Soil Moisture Active Passive (SMAP) instrument may help answer that question. Scheduled for launch on 29 January 2015, SMAP was built and will be operated by NASA's Jet Propulsion Laboratory, Pasadena, California.
Scientist Randy Koster of NASA's Goddard Space Flight Center, Greenbelt, Maryland, has found specific regions of the globe where soil moisture appears to be especially influential on local weather. These "hot spots," as Koster calls them, encompass only about 10 percent of Earth's land surface. However, they include three important agricultural areas: the U.S. Midwest, northern India and the African Sahel.
Koster and his colleagues found the hot spots during a study of 12 global climate models that focused on how the models' land processes affected rainfall and temperature. They devised an experiment to isolate how much of the natural variation in rainfall and temperature around the globe is due to variations in soil moisture.
Image credit: Wikimedia Commons - Northern India