Advantages and limitations of satellite-based snow data
ADVANTAGES | LIMITATIONS |
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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. |