Dogsleds Take Scientists to Arctic to Measure Earth Snow Levels

Melting snow feeds rivers that supply water to billions worldwide

An expedition into the frozen Arctic using dogsled teams kicked off March 12 from Alaska to help NASA find out how much snow blankets the Earth.

The trek is one leg of a multisponsor, five-year GoNorth! expedition of multiple dogsled treks that will explore the Arctic in pursuit of environmental samples and observations, according to a March 17 NASA press release.

The NASA-funded project is a collaborative effort with the University of Minnesota, the U.S. Department of Agriculture (USDA), the National Oceanic and Atmospheric Administration, the U.S. Geological Survey, the Meteorological Service of Canada, Quebec, and several universities in the United States, Canada and Europe.

More than 3,000 classrooms around the world are learning along with Go North! through distance-learning program with materials for kindergarten through grade 12.

The Trek

Seven explorers, including scientists and teachers, began at Circle, Alaska, and will travel to the Arctic through May with two dog teams of 25 polar huskies - a mixed breed of Northern native huskies with double coats of fur and strong legs - to collect samples of snow data.

The samples, to be gathered in five communities across the Alaskan Arctic, will be analyzed to help validate snow-pack observations from NASA's Aqua satellite. Snow pack refers to snow that remains on the ground for weeks at a time.

Researchers hope analyzing the snow samples also will improve understanding of how snow changes after it lands on Earth.

Snow crystals scatter microwave radiation that emanates from the ground. Researchers want to know more about what kinds of crystals are more likely to be found in a particular region at a particular time of year.

The more information they have about snow crystals from various areas of the snow-covered portion of the globe, the better they are positioned to understand and interpret the satellite-derived data.

"In recent years, snow cover has been declining in many areas of the globe," said physical scientist James Foster of NASA's Goddard Space Flight Center in Maryland.

It is increasingly important to measure accurately the amount of snow in large areas where melted snow drains into waterways, he said, so public officials better can determine how to manage limited water resources.

World Water From Snow

The ability to accurately measure snow packs has implications all over the globe.

"Melting snow in the Himalayan region, for example," Foster said, "feeds rivers that supply water to over a half billion people. So it's key for us to better understand how much water is made available on a worldwide scale from melting snow packs."

The Advanced Microwave Scanning Radiometer-EOS (AMSR-E) instrument aboard the Aqua satellite can measure snow in remote areas where ground and air surveys are difficult.

But the satellite measures must be validated to ensure that the data from space are reliable. Validating snow measurements is especially difficult in regions where the terrain is not uniform, posing a challenge for the AMSR-E sensors.

That is where the dogsled teams come in. They will gather data from very remote locations to help confirm the satellite observations.

"The dogs are the superstars of the project," said expedition leader Paul Pregont of the University of Minnesota. "Without their abilities to get us from point A to point B, we could not conduct this kind of critical work."

At each data-collection point, researchers will dig a snow pit, confirm the location, air temperature and snow depth. They then will collect snow crystals from the snow pit at different depths.

The samples will be stored in liquid nitrogen and shipped to the USDA Beltsville Agricultural Research Center in Maryland, where the crystals will be imaged with a low-temperature scanning electron microscope to measure their size and denote their shape.

Information about AMSR-E is available at the NASA Web site.

The GoNorth! distance learning program can be viewed on a University of Minnesota Web site.

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