A new tool developed by USDA’s National Agricultural Statistics Service in collaboration with NASA and George Mason University provides access to high-resolution NASA data on soil moisture.
The tool, Crop Condition and Soil Moisture Analytics (Crop-CASMA), provides access to NASA’s Soil Moisture Active Passive (SMAP) mission and the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument in a user-friendly format. Crop-CASMA is available at https://cloud.csiss.gmu.edu/Crop-CASMA/.
According to Rajat Bindlish, a research associate in earth science remote sensing at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, the tool provides more thorough spatial coverage and consistency than other soil moisture measurement methods.
Some of Crop-CASMA’s primary users will be NASS researchers and statisticians who release weekly Crop Progress Reports that classify states into moisture categories (very short, short, adequate, surplus). The reports also track crops’ health and growing progress.
“USDA researchers and statisticians will incorporate the tool into a range of applications,” said NASS Spatial Analysis Research lead Rick Mueller. “For example, Crop-CASMA can help identify areas that could not be planted because of wet, saturated, frozen, excessively dry, or inaccessible fields resulting in improved planted statistical acreage estimates.”
In addition to supporting agricultural operations, Crop-CASMA will enable research on sustainability and the impact of extreme weather events. “These satellite-derived vegetation condition indices and soil moisture condition maps show first-hand the ever-changing landscape of U.S. agriculture,” Mueller said.
The tool is formatted to be accessible to private users, according to Crop-CASMA project leader Zhengwei Yang, a USDA geographer and co-investigator of the High-Resolution Soil Moisture Development Project.
“We created an easy-to-use interface that requires little technical background to use,” said Yang. “There’s a tool to select an area and create a map you can save as a PDF, and you can also download data from the web to input into your model.”
This work was supported by NASA Applied Sciences’ Earth Science Division's Western Water Applications Office (WWAO) and the NASA Terrestrial Hydrology Program.
SMAP data, the foundation for Crop-CASMA, draw from the topsoil and rootzone levels, or from the surface to roughly 3 feet (1 meter) underground. Raw SMAP data have a 36-kilometer (roughly 20-mile) spatial resolution, meaning each data “footprint” is about the size of a county. The team also developed a data analysis method to estimate a higher-resolution soil moisture product using SMAP and land surface data, giving users information at 1-kilometer (0.62-mile) resolution.
Having the data in finer resolution allows users to more accurately pinpoint areas of high or low moisture. “Our current reports are at the state level,” Yang said. “One state may be categorized on average as ‘wet,’ but the whole state might not actually be wet. These new data deliver localized moisture readings – this is what matters to the farmer.”
This collaboration is part of a larger, recently signed agreement between USDA and NASA to jointly strengthen agricultural and earth science research.
“Having the SMAP soil moisture data going directly to the users at NASS realizes one of the key goals of the mission,” said Simon Yueh, SMAP project scientist at JPL. “A strong collaboration between NASA and USDA has made this possible.”