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This is a photograph taken along the Columbia River Gorge, at the southern edge of the Gifford Pinchot National Forest. The Forest is located in southwest Washington State, and now contains 1,312,000 acres and includes the 110,000-acre Mount St. Helens National Volcanic Monument established by Congress in 1982. Because snowpack is a major water resource in the Western U.S, an accurate forecast of snow amounts is essential to managing the water supply in that region. This research looks at how El Nino/Southern Oscillation cycles could be used as a factor to predict snowpack evolution in the Columbia and Colorado River basins.

• Credit: Roger Peterson, US Forest Service, Gifford Pinchot National Forest

• Source: http://www.gsfc.nasa.gov/topstory/2003/0210snowpack.html archive copy at the Wayback Machine

Secondary source: http://en.wikipedia.org/wiki/Image:Columbia_River_Gorge.jpg

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