Who says kids are the only ones who like to play in the snow? Some adults love it, too. And the researchers out in the Colorado Rockies this time of year must be having a ball. They are just completing the second year of the Cold Land Processes Field Experiment (CLPX), a multi-organizational study of snowpacks. The National Oceanic and Atmospheric Administration (NOAA) along with university students and scientists from five federal agencies are looking at snow-covered ground from within the snowpack itself, as well as air and space, in an effort to learn more about the weather in cold climates.

It's a part of science known as the "terrestrial cryosphere." These are regions where water is frozen either seasonally or permanently, and vegetation exists with frozen soil and ice.

Why is this terrestrial cryosphere so important? After all, isn't a deep snowpack out in the Rockies a good thing? The ski resorts love it and the snowmelt in the spring results in a good water supply for the western reservoirs. The cryosphere represents quite a large area of the Earth's surface. From satellite imagery, it is estimated that over 60% of the Northern Hemisphere land surface has snow cover in midwinter. More than 30% of the Earth's surface has seasonal snow cover, including around 10% that is permanently covered with snow and ice.

This large amount of frozen water represents a large part of the Earth's hydrologic system, i.e. the water supply. If scientists can master the methods of observing this snow cover around the world, they can better measure the potential reserve of water or the potential onset of drought.

The CLPX is quite a project. It includes scientists digging in deep within the snowpack out west in order to sample the characteristics of the snow, the water content, the structure, etc. and compare these findings with what is observed from research aircraft and satellites looking down from above. The scientists on the ground will use skis, snowshoes and over-the-snow vehicles to reach various sites in this rugged terrain.

Each researcher will carry 30-pound backpacks containing shovels, probes, radios, scales, and GPS (Global Positioning System) equipment. They want to determine how the snowpack changes with time, including the melting process, temperature of the snowpack, and the grain and crystal structure of the snow at various depths. Some of the snow pits will be dug to a depth of over nine feet.

Meanwhile, flying overhead will be various aircraft equipped with sensors that will look down on the snow-covered landscape. The sensors will measure gamma radiation to determine the water equivalent of the snow. Satellite imagery from space will also observe the various wavelengths of energy emitted by the snow.

Eventually scientists hope to use the findings from this field experiment to better understand the formation and changes of snowpacks, especially the timing and extent of melting snow. This will help scientists to understand which part of snowpack changes are due to natural cycles and which are due to global warming. It will also help in flood forecasting and avalanche detection and prediction. To take a look at some of the products already being produced from this research, check out the web site of the National Operational Hydrologic Remote Sensing Center at nohrsc.nws.gov/.

Most of us don't think snow cover and the snowpack is too interesting. Some of us like to ski and snowmobile on it. But is all of this scientific research necessary just to understand snow? In Wisconsin, snow plays an important part in our economy. The water from winter snowmelt is crucial for proper moisture in the farm fields this spring. But in other parts of the world, snow is even more important. And because it covers such a large area of our planet at any one time, knowing the nature of snow inside and out is crucial to Earth's ecosystem.