Scientists working with data from NASA’s Aquarius instrument have released worldwide maps of soil moisture, showing how the wetness of the land fluctuates with the seasons and weather phenomena.
Soil moisture, the water contained within soil particles, is an important player in Earth’s water cycle. It is essential for plant life and influences weather and climate. Satellite readings of soil moisture will help scientists better understand the climate system and have potential for a wide range of applications, from advancing climate models, weather forecasts, drought monitoring and flood prediction to informing water management decisions and aiding in predictions of agricultural productivity.
Launched June 10, 2011, aboard the Argentinian spacecraft Aquarius/Satélite de Aplicaciones Científicas (SAC)-D, Aquarius was built to study the salt content of ocean surface waters. The new soil wetness measurements were not in the mission’s primary science objectives, but a NASA-funded team led by U.S. Department of Agriculture (USDA) researchers has developed a method to retrieve soil moisture data from the instrument’s microwave radiometer.
The Aquarius measurements are considerably coarser in spatial resolution than the measurements from the upcoming NASASoil Moisture Active Passive (SMAP) mission, which was specifically designed to provide the highest quality soil moisture measurements available, including a spatial resolution 10 times that offered by Aquarius.