Arctic Sea Ice Charts from Danish Meteorological Institute, 1893-1956

Danish Meteorological Institute (DMI) sea ice charts provide observed and inferred ice extent for each summer month from 1893 to 1956. The collection consists of 266 scanned image files containing 291 individual charts, based on compiled reports from ships, expeditions, and shore observers. This dataset offers a long-term visual record of Arctic ice conditions before the satellite era.

Use Cases

• Analyzing historical summer sea ice extent and concentration changes in the Arctic.
• Training computer vision models to digitize and classify ice edges from scanned chart images.
• Comparing pre-satellite era observational data with modern remote sensing records.
• Studying the methods and network of early 20th-century polar observation and data compilation.

Strengths

• Covers a 64-year time series from 1893 to 1956, providing a long historical baseline.
• Contains 291 individual chart images derived from a multi-source observational network.
• Cross-platform presence on Data.gov and NASA EarthData signals recognized scientific importance.

Limitations

• Ice edges are partly inferred where direct observations were lacking, introducing unquantifiable error.
• Sources conflict on the last updated date (2026-03-13 vs. 1956-08 31), creating uncertainty about metadata maintenance.
• The dataset provides image scans, not digitized gridded data; quantitative analysis requires further processing.

Provenance

Source

Danish Meteorological Institute (DMI), scanned by the Icelandic Meteorological Office (IMO).

Collection Method

Compiled observations from a variable network of national organizations, shore observers, expeditions, and ships, with expert extrapolation for missing data.

Time Range

1893 to 1956

Freshness

2026-03-13 14:56:03.476215

Geography

Arctic region