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Blast off to better soil moisture measures

A NASA satellite to measure water in Earth’s soil has gone into orbit

NASA rocket launch

An unmanned Delta 2 rocket lifted off from the Vandenberg Air Force Base in California Jan. 31 carrying a NASA satellite to measure moisture in the top layer of the Earth’s soil, data to be used in weather forecasting and tracking of global climate change.

Soil moisture is a variable that binds together all of the planet’s environmental systems, scientists say. More precise data will enable forecasters and policy-makers to deal more effectively with drought or flooding in specific regions.

“It’s the metabolism of the system,” said Dara Entekhabi, lead scientist of NASA’s Soil Moisture Active Passive (SMAP) observatory.

Perched on top on the 39-metre rocket was NASA’s 2,100-pound (950-kg) SMAP, which will spend at least three years measuring the amount of water in the top two inches of Earth’s soil.

Overall, soil moisture accounts for less than one per cent of the planet’s total water reservoir, with 97 per cent in the planet’s oceans and nearly all of the rest locked in ice, said Entekhabi.

Currently, scientists rely largely on computer models to estimate soil moisture.

But from an orbit 426 miles (685 km) above Earth, SMAP has two microwave instruments to collect exact soil moisture measurements everywhere on Earth and update the measurements every two or three days.

“This data will benefit not only scientists seeking better understanding of our planet’s climate environment, but it’s also a boon for weather forecasters, agriculture and water resource managers, emergency planners and policy-makers,” NASA deputy associate administrator Geoffery Yoder, said after the launch.

SMAP joins 19 other NASA satellites keeping tabs on Earth’s land, seas and atmosphere.

Manitoba soil scientists and flood forecasters will be among the beneficiaries.

Extreme weather and wetter-than-usual conditions make SMAP satellite research timely, University of Manitoba soil scientist Paul Bullock told the Manitoba Co-operator in December.

Soil moisture distribution is an important input variable that goes into flood risk models because the amount of water in the soil changes how much precipitation can be stored and how much runs off into streams and rivers.

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