Focus Area on Snow Product Validation
Carrie Vuyovich, NASA Goddard Space Flight Center, USA
Juha Lemmetyinen, Finnish Meteorological Institute, Finland
Snow Product Definitions
The IPCC 6th Assessment Report defines satellite snow cover extent (SCE) as the areal extent of snow-covered ground, which can be expressed as binary or as a fraction.
The variable snow water equivalent (SWE), is the depth of liquid water that would result if a mass of snow melted completely.
Units:
Binary snow cover: snow/non-snow.
Snow cover fraction: expressed as a percentage or m2.
Snow Water Equivalent (SWE) : mm w.e. or kg m-2
Highest Validation Stage Currently Reached for Satellite-Derived Snow Cover Products
Validation stage 1-2 (LPV validation stage hierarchy) - The highest LPV validation stage reached for satellite-derived snow cover products. Limitations to reaching a higher validation stage include a limited number of validation sites, spatial and temporal gaps of in situ reference data coverage.
- Binary snow cover: LPV Stage 2
- Fractional snow cover: LPV stage 2
- Snow water equivalent: LPV stage 1
Validation Good Practices
Snow extent and SWE validation good practices will be compiled on the ESA Satellite Snow product Intercomparison and Evaluation Experiment (SnowPEx). See the SnowPEx documents page.
Snow Cover Validation Reference Data Sets
Open reference data sets are available from several sources, such as:
USA:
European Alps: Observed snow depth trends in the European Alps: 1971 to 2019
Global:
- International Network for Alpine Research Catchment Hydrology (INARCH) Research Basins
- WMO World Weather Watch (WWW)/Global Observing System (GOS) surface synoptic network (depth). This web site provides multiple links to National Networks (depth and snow water equivalent).
LPV Focus Areas
Meetings
EARSEL: Remote Sensing of the Cryosphere: methods and applications from regional to global scale, 6 - 8 Feb 2023, University of Bern, Switzerland.
