NASA soil moisture mission begins beaming key science

Washington: NASA’s new Soil Moisture Active Passive (SMAP) mission to map global soil moisture and detect whether soils are frozen or thawed has begun science operations.

The first global view, a combined active-passive soil moisture map with a spatial resolution of nine km, shows dry conditions in the southwestern US and in Australia’s interior.

Moist soil conditions are evident in the US Midwest and in eastern regions of the US, Europe and Asia.

“SMAP data will eventually reveal how soil moisture conditions are changing over time in response to climate and how this impacts regional water availability,” said Dara Entekhabi, science team leader at the Massachusetts Institute of Technology in Cambridge.

SMAP data will be combined with data from other missions like NASA’s Global Precipitation Measurement, Aquarius and Gravity Recovery and Climate Experiment to reveal deeper insights into how the water cycle is evolving at global and regional scales.

Launched on January 31 on a three-year mission, SMAP will help scientists understand links among Earth’s water, energy and carbon cycles and reduce uncertainties in predicting climate.

It will also enhance our ability to monitor and predict natural hazards like floods and droughts.

SMAP data have additional practical applications, including improved weather forecasting and crop yield predictions.

“Fourteen years after the concept for a NASA mission to map global soil moisture was first proposed, SMAP now has formally transitioned to routine science operations,” added Kent Kellogg, SMAP project manager.

SMAP’s two instruments produce the highest-resolution, most accurate soil moisture maps ever obtained from space.

The spacecraft’s radar transmits microwave pulses to the ground and measures the strength of the signals that bounce back from the Earth, whereas its radiometer measures microwaves that are naturally emitted from Earth’s surface.