A global englacial temperature database (glenglat)

Ice temperature is an important characteristic of any glacier. It influences glacier dynamics, subglacial hydrology, glacier retreat behavior, and potential glacier hazards. Additionally, ice temperature can serve as an archive of past air temperature changes and be used for climate reconstructions and validation of thermo-mechanical glacier models. Measuring (deep) ice temperatures, however, is very laborious and costly, and most  ice temperature measurements are hidden away in publications that span almost a century.

To overcome the gap between data availability and data need, we have compiled ice temperature data from 132 glaciers in an open-source, version-controlled database available to the scientific community. This global englacial temperature database (glenglat; https://github.com/mjacqu/glenglat) contains temperatures measured in 410 different boreholes in the Americas, Greenland, Eurasia, Africa, and Antarctica between 1938 and 2023. Roughly 20% of all boreholes are known to have reached the glacier bed; the deepest borehole is 743 meters deep; and most measurements are from cold or polythermal glaciers. Data for 369 boreholes were extracted from published literature while data for the remaining 41 boreholes were directly submitted to the authors.

The database is structured following the Frictionless Data Tabular Data Package specification. The data are stored as comma-separated-value (CSV) files and the metadata are provided in a single YAML file – text formats which are both human and machine readable. Following a standard structure provides two key advantages: First, upon any change to the data or metadata, the structure and content of the database can automatically be validated using existing software. Second, documentation and data submission templates can be rendered automatically from the machine-readable metadata, which lowers the bar for data maintainers and future contributors. We hope that glenglat can serve many glaciological applications and become the  repository of choice for future ice temperature measurements.