A standardized permafrost ground temperature collection for Canada 2025

Abstract

Ground temperature (GT) is an essential variable for monitoring the thermal state of permafrost, developing models, and conducting fundamental research. However, the usability of GT data in Canada is often hampered by inconsistent file formats, a lack of metadata standardization between organizations, and varied temporal resolutions. This fragmentation has prevented the development of a comprehensive benchmark dataset, leaving researchers reliant on small, ad-hoc data subsets for model evaluation. To address this gap, we present a new, standardized collection of GT and ground surface temperature (GST) data from across Canada, designed to serve as a benchmark for synthesis and model evaluation. The collection integrates data from 29 published datasets and 13 unpublished contributions, encompassing 427 GT and 491 GST sites across British Columbia, Labrador, Northwest Territories, Nunavut, Québec, and Yukon. The dataset includes records from 1960 through 2025 and observations range in depth from 0 to 300 m. The longest individual time series comprises 34 consecutive years of daily data with no more than 10 % missing data per year. On average for all sites and depths, this value is 6 years. All included time series feature at least one year of measurements at daily resolution. We performed quality control and standardization using tempcf – a newly-developed python software tool – to document and remove anomalies, outliers, and drilling disturbances. Then we aggregated sub-daily data to daily means. The dataset is standardized into NetCDF files adhering to CF, ACDD, and IOOS metadata standards as well as a compatible permafrost-specific metadata profile. Data are provided as both individual NetCDF files and text files. They are fully accessible at https://doi.org/10.5281/zenodo.18022924 (version 0.9.1) (Meier-Legault et al., 2025) and via an ERDDAP server (https://data.permafrostnet.ca/erddap, last access: 21 July 2026), following FAIR principles. Several limitations remain, including time zone uncertainty in some datasets, and the lack of a standardized methodology for harmonizing site description metadata. Nevertheless, this collection improves the accessibility and usability of Canadian ground temperature data for national-scale permafrost research.