Advantages and limitations of satellite-based snow data

ADVANTAGES LIMITATIONS
Spatial coverage - satellite instruments can provide information over a wide range of spatial scales (global, hemispherical, regional, and local). Accuracy - land and snow cover may change within a pixel, which can lead to erroneous results when comparing it to the ground-based measurements.
Spatially consistent information - data from satellite instruments is homogeneous over the scanned area. Temporal discontinuity due to the cloud cover - instruments working in the visible and infrared spectrum are affected by the clouds and it significantly reduces data availability in the regions of frequent cloud cover.
Microwave sensors have all-weather monitoring capability - the snow retrievals obtained by the space-borne passive microwave radiometer has the advantage of being insensitive to cloud cover. Visible bands may be used only during the day - ice and snow cover can be detected in visible bands only during the day, when sun light is reflected.
Satellite based snow products are generated automatically - automatic algorithms and procedures help to provide data for the end user in spatially consistent and timely manner. SWE and other snowpack characteristics derived from satellite data may be erroneous due to the effects of lakes and forest or due to very thick or shallow snow cover.
Satellite instruments can provide information in data sparse regions - in some areas of Arctic or Siberia satellite based snow cover information can be the only data source available. Snow detection in mountainous regions is limited - it is challenging to correctly determine surface conditions in the alpine regions due to various factors, e.g. land cover variability, topography, terrain shadows.