Northern Hemisphere EASE-Grid Annual Freezing and Thawing Indices, 1901-2002

Northern Hemisphere land areas are covered by this dataset of annual freezing and thawing indices from 1901 to 2002. It provides gridded estimates of cumulative degree-days below and above 0°C, calculated from monthly mean air temperature data sourced from the University of East Anglia Climate Research Unit. The data is formatted on a 25 km resolution Equal-Area Scalable Earth Grid (EASE-Grid).

Use Cases

• Modeling permafrost distribution and active layer thickness based on cumulative degree-day indices.
• Analyzing long-term trends in seasonal freezing and thawing cycles across the Northern Hemisphere.
• Validating climate and land surface models using gridded historical temperature-derived metrics.
• Studying the impact of climate change on cold region hydrology and ecosystems using the century-long time series.

Strengths

• Provides a century-long, consistent time series from 1901 to 2002.
• Offers spatially explicit data on a standardized 25 km EASE-Grid for the entire Northern Hemisphere.
• Derived from a reputable source: the University of East Anglia Climate Research Unit global land temperature data.

Limitations

• Metadata completeness is low; specific column names and exact row/record counts are unavailable.
• Data freshness is a concern; the underlying temperature record ends in 2002, and the dataset itself has not been updated with more recent decades.
• A conflict exists in the 'last updated' metadata between platforms, with dates ranging from 2002 to a future date in 2026.

Provenance

Source

National Aeronautics and Space Administration (NASA). Values calculated from University of East Anglia Climate Research Unit (CRU) global land temperatures.

Collection Method

Calculated from monthly mean air temperature data (Mitchell and Jones, 2005) to derive cumulative annual degree-days.

Time Range

1901 to 2002

Freshness

The core data covers up to 2002. Platform metadata shows conflicting 'last updated' dates of 2002-12-31 and 2026-04-09.

Geography

Northern Hemisphere land areas on the Equal-Area Scalable Earth Grid (EASE-Grid).