Snow Cover Detection {Methodology Using Landsat}

The global significance of snow and ice is profound and seasonal patterns of snow are an important part of the climate and bio system of the Earth. Snow cover helps to regulate the temperature of the Earth's surface through its reflection of solar radiation and thermal insulation qualities. Snow contributes to the hydrologic cycle through precipitation storage and melting. Near the poles snow covers the ground all year round, however in lower latitudes the coverage is seasonal and depends on factors such as air temperature and altitude.

 

Accurate data is key to understanding Earth's climate and bio system processes and learning in order to protect and maintain them. The Moderate Resolution Imaging Spectroradiometer (MODIS) gathers global images daily and from these snow cover is commonly detected. However, the low resolution of these images do not allow snow cover to be analyzed at a regional or local scale. 

 

The goal of this project is to construct a more accurate method of snow cover detection using high resolution images obtained by the Landsat 4 and Landsat 5 satellites. A consistent, accepted method has not been developed using Landsat for accurate snow cover detection that can be used over a large area. 

 

Using several reflectance bands from Landsat images, a ratio called the Normalized Difference Snow Index (NDSI) will be used to detect snow cover.