WHY STUDY LAKE ICE AND SNOW?

Introduction

Snow cover and frozen lakes and ponds are a critical water resource in many areas. More than 75 percent of the water for human consumption and irrigation in the western United States comes from snow melt runoff.

The presence of snow significantly modifies land/atmosphere interaction because of its high albedo and its low thermal conductivity (i.e., its ability to transfer heat from layer to layer). Similarly, the presence of an ice cover on a pond, lake or river has an impact on the water/atmosphere interactions.

Source: All images NASA

A MODIS image of snow cover extent over North America on 16 October 2001.

For three quarters of the year Alaska is covered by snow and ice (over 1.7 million km² or almost 657 million mile² of land). This MODIS image was taken on 29 March 2002.

A MODIS image acquired on 7 June 2002, show that the snow has melted from the tundra on the North Slope of Alaska (brown) but that most of the lakes are still frozen (white). Beaufort Sea and Chukchi Sea sea ice can seen all along the coast.