Standardised Snow Pack Index: Snow Water Equivalent Anomalies from ERA5 Reanalysis

1978 to present standardized snow water equivalent (SWE) anomaly index derived from ERA5 reanalysis data and a snow model. The Standardized Snow Pack Index (SSPI) measures how average SWE over 10- or 30-day periods compares to the long-term expected value for 1981-2020, where 0 represents normal conditions. It is produced by Eurac Research using a modified SNOWGRID-CL model with downscaled Copernicus Climate Change Service and Atmosphere Monitoring Service data.

Use Cases

• Monitoring snow drought conditions based on the standardized deficit/surplus index values.
• Assessing seasonal water supply forecasts based on snow water equivalent anomalies.
• Validating hydrological and climate models using long-term snowpack index data.
• Analyzing trends in snowpack variability over time based on the 1978-present time series.

Strengths

• Long-term temporal coverage from 1978 to the present year.
• Standardized index methodology (gamma distribution) allows for consistent anomaly comparison.
• Based on downscaled ERA5 reanalysis data and a deterministic snow model (SNOWGRID-CL).
• Provides indices for two averaging periods (10-day and 30-day).

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count and spatial resolution are unknown, which may limit suitability assessment.
• Last update date is unknown; freshness unverified.

Provenance

Source

Eurac Research, using modified Copernicus Climate Change Service and Copernicus Atmosphere Monitoring Service information.

Collection Method

SSPI calculated from daily SWE timeseries derived using a modified SNOWGRID-CL snow model with downscaled ERA5 reanalysis as input.

Time Range

1978 to present, with long-term reference period 1981-2020.