Long-Term Drought Grips the Western U.S. – Soils and Plants Are Parched
For the second year in a row, drought has overtaken much of the United States from the Rocky Mountains to the Pacific Coast.
For the second year in a row, drought has parched much of the United States from the Rocky Mountains to the Pacific Coast. Following one of the planet’s warmest years on record, and with precipitation this year well below average in the western U.S., scientists and government agencies are watching for diminished water resources and potentially severe fire seasons.
According to the June 10 report from the U.S. Drought Monitor, 88.5 percent of the land area in the West—defined as California, Nevada, Arizona, New Mexico, Utah, Idaho, Montana, Oregon, and Washington—is experiencing some level of drought, with 55 percent being classified as “extreme.” An estimated 90 percent of Utah is under extreme drought conditions, with 64 percent rated “exceptional” (the worst classification). Similar conditions are reported across Arizona (87 percent extreme), California (85 percent), and Nevada (76 percent). More than 58 million people are living with the dry conditions in the region.
The map above offers one indicator of the conditions on June 5, 2021. Using data from the Crop Condition and Soil Moisture Analytics (Crop-CASMA) product, the map shows soil moisture anomalies, or how the water content in the top meter (3 feet) of soil compares to normal conditions for the time of year. Crop-CASMA integrates measurements from NASA’s Soil Moisture Active Passive (SMAP) satellite and vegetation indices from the Moderate Resolution Imaging Spectroradiometer (MODIS) instruments on NASA’s Terra and Aqua satellites.
Released in April 2021, the Crop-CASMA portal offers soil moisture information more frequently (every 2 to 3 days) and on smaller scales (down to the level of towns and counties instead of states) than many other data products. Farmers and resource managers can use soil moisture data to help time crop planting and irrigation, to forecast yields, and to track droughts and floods. The product was developed by scientists at the U.S. Department of Agriculture (USDA), George Mason University, and NASA’s Goddard Space Flight Center and Jet Propulsion Laboratory. One of the primary users of the dataset is the USDA’s National Agricultural Statistics Service.