This dataset is an individual fire event database spanning the circumpolar Arctic-boreal domain. The dataset provides ignition locations and 12-hourly fire perimeters and active fire lines for all Arctic-boreal fires between 2012 and 2023. Vector-based perimeters were retrieved from 375m Visible Infrared Imaging Radiometer Suite (VIIRS) active fire detections using an Arctic-boreal specific fire tracking algorithm. In particular, the algorithm was designed to handle very large fires with fragmented fire detections, very long smouldering times and deriving accurate fire perimeters in landscapes fragmented by many surface water bodies. Archive active fire data from VIIRS was used for 2012 to 2021, and near-real time VIIRS data for 2022 and 2023, when archive data was not available. This object-based fire event data allows for the characterization of fire types and fire regimes in the Arctic-boreal domain, and may be of use for validating and improving operational fire spread models used in fire management as well as global fire models.

Data is provided per calendar year. Each year's directory contains a subdirectory 'Snapshot' with 12-hourly fire perimeters (all active fire perimeters of a time step) and active fire lines (files ending on *_FL.gpkg), and a subdirectory 'NFP' with text files containing the original active fire location information associated with each fire at each time step. The two additional folders 'final_perims' and 'ignitions' contain annual summary vector files of all ignitions and final perimeters. The attributes of all types of outputs (snapshots, new fire pixel files, final perimeters and ignitions) are described in detail in the provided pdf.