SMOS Helping To Sift Through Wetlands
March 22, 2013

SMOS Helping To Sift Through Wetlands

Lee Rannals for — Your Universe Online

The European Space Agency's SMOS satellite is showing its worth in observing the wetlands, offering a better understanding of Earth's carbon cycle.

SMOS is a multifaceted satellite capable of mapping soil moisture and ocean salinity, and its novel microwave sensor is able to capture images of brightness temperature to obtain this information. The satellite has been used to map freezing soil, monitor thin Arctic sea ice, determine wind speeds under hurricanes, and to monitor ocean eddies. Now, ESA scientists are adding wetland monitoring to SMOS' repertoire.

Scientists say the wetlands are important resources of fresh water and are rich in biodiversity. These flooded areas also emit large quantities of methane, contributing more of the gas to the atmosphere than any other natural source.

Methane is an even more powerful greenhouse gas than carbon dioxide. Scientists estimate atmospheric methane was responsible for about 20 percent of the rise in global temperatures last century. Methane emissions are mostly a result of human activity, but wetlands are thought to be responsible for about 20 to 40 percent of global emissions.

Greenhouse gas emissions originating from drained wetlands are about equal to what industrial factories have given off. Experts from the University of Gothenburg and the Swedish University of Agriculture Sciences said drained wetlands comprise as much as ten percent of Sweden's total surface area. The University said these once grained wetlands have become a "significant source of greenhouse emissions."

SMOS will help uncover valuable information about the role wetlands play in the carbon cycle and how they contribute to atmospheric methane.

“SMOS offers the opportunity to implement fast and easy single satellite algorithms for monitoring wetland areas," said Catherine Prigent from the Paris Observatory. “This complements current methods of analysis that require a lot of work to blend the different products.”

A future program, known as the GlobWetland II project, could help add a better understanding of the wetlands as well. Under this project, high-resolution optical data from satellites like the Sentinel-2 mission could be combined with the coarse resolution SMOS has to offer to make optical use of available, remotely-sensed information.

ESA's GlobWetland II project is helping Mediterranean countries monitor wetlands. Urban settlements around this area have flourished, which has increased waste water. Tools from the project have shown that the wetland area increased by about half a square mile between 1978 and 1990.