Soil moisture is essential for seeds to germinate and for crops to grow. But record droughts and scorching temperatures in certain parts of the globe in recent years have caused soil to dry up, crippling crop production. The falling food supply in some regions has forced prices upward, pushing staple foods out of reach for millions of poor people.
NASA researchers are using satellite data to deliver a kind of space-based humanitarian assistance. They are cultivating the most accurate estimates of soil moisture the main determinant of crop yield changes and improving global forecasts of how well food will grow at a time when the world is confronting shortages.
During a presentation this week at the the Joint Assembly of the American Geophysical Union in Toronto, NASA scientist John Bolten described a new modeling product that uses data from the Advanced Microwave Scanning Radiometer for EOS (AMSR-E) sensor on NASA's Aqua satellite to improve the accuracy of West African soil moisture. The group produced assessments of current soil moisture conditions, or "nowcasts," and improved estimates by 5 percent over previous methods. Though seemingly small and incremental, the increase can make a big difference in the precision of crop forecasts, Bolten said.
The modeling innovation comes at a time when crop analysts at agencies like the U.S. Department of Agriculture (USDA) are working to meet the food shortage problem head on. They combine soil moisture estimates with weather trends to produce up-to-date forecasts of crop harvests. Those estimates help regional and national officials prepare for and prevent food crises.
"The USDA's estimates of global crop yields are an objective, timely benchmark of food availability and help drive international commodity markets," said Bolten, a physical scientist at NASA's Goddard Space Flight Center, Greenbelt, Md. "But crop estimates are only as good as the observations available to drive t
|Contact: Sarah DeWitt|
NASA/Goddard Space Flight Center