In the following, truly existing snow or truth refers to the snow information from weather stations. Interpretation refers to the Earth observation-based snow information (FSC). All the metrics are derived from comparison pairs of weather stations observations (truth) and of FSC provided over its location (interpretation). The metrics are designed to described FSC-product in general although they are calculated from the comparison pairs only.

NTOT: Number of weather station observations for which satellite data-based FSC is available.

EO-COVERAGE (0-100%): Percentage of weather stations for which FSC interpretation is available.

PRECISION (0-100%): Describes how precisely the ‘snow’ in the FSC-interpretation reflects the truly existing snow (more information).

RECALL (0-100%): Describes the ability of FSC -interpretation to recognize truly existing snow (more information).

FALSE ALARM RATE (FAR 0-100%): Describes the tendency of FSC-product to interpret snow-free areas as snow (more information).

F-SCORE (0-100%): Describes the ability of FSC -interpretation to recognize truly existing snow, and a the same time, the ability to avoid interpreting snow-free areas as snow (more information).