Snow and Ice -- From Satellites
Satellites are in an excellent position to gather information about snow coverage over large areas. Data from satellites is used to determine how much a glacier has increased or decreased in size from one year to the next and the distance from the glacier or snow pack to the satellite. This measurement lets scientists know how much thicker or thinner a glacier is from one year to another. Satellite data can't be used to measure the thickness of snow or a glacier. Perhaps one day, one of your students will find a way to use satellites to measure the exact thickness of the snow pack or glacier.
The Polar and Geostationary Operational Environmental Satellite programs, also known as GOES and POES, operated by NOAA, provide valuable imagery. Clear-sky imagery from both the POES and the GOES sensors show snow and ice boundaries. However, cloud cover near a snowline may prevent the GOES and POSE satellites from collecting relevant data. When this happens, data from other satellites can be used to fill in the gaps.
The Moderate Resolution Imaging Spectro-Radiometer, or MODIS, instrument on NASA's Terra and Aqua satellites also provides data to create images that are used to monitor snow cover over large areas of Earth. NASA's Earth Observatory Web site accurately describes both Terra and Aqua missions and their orbits.