Large forest fires in Canada, 1959–1997

TLDR

Large fires account for only 3.1 % of Canadian fires but ~97 % of the area burned, enabling landscape‑scale analysis of fire impacts, with most activity occurring June–July due to lightning in northern Canada. The LFDB compiles data on all Canadian fires over 200 ha from 1959–1997, recording location, date, size, cause, and suppression, and is updated yearly and extended backward to support long‑term trend analysis. Large fires burn an average of ~2 million ha per year (up to 7 million), disproportionately affecting boreal and taiga ecozones, with lightning responsible for 80 % of the area, and nearly half of Canada’s burned area comes from fires that are not suppressed.

Abstract

A Large Fire Database (LFDB), which includes information on fire location, start date, final size, cause, and suppression action, has been developed for all fires larger than 200 ha in area for Canada for the 1959–1997 period. The LFDB represents only 3.1% of the total number of Canadian fires during this period, the remaining 96.9% of fires being suppressed while <200 ha in size, yet accounts for ∼97% of the total area burned, allowing a spatial and temporal analysis of recent Canadian landscape‐scale fire impacts. On average ∼2 million ha burned annually in these large fires, although more than 7 million ha burned in some years. Ecozones in the boreal and taiga regions experienced the greatest areas burned, with an average of 0.7% of the forested land burning annually. Lightning fires predominate in northern Canada, accounting for 80% of the total LFDB area burned. Large fires, although small in number, contribute substantially to area burned, most particularly in the boreal and taiga regions. The Canadian fire season runs from late April through August, with most of the area burned occurring in June and July due primarily to lightning fire activity in northern Canada. Close to 50% of the area burned in Canada is the result of fires that are not actioned due to their remote location, low values‐at‐risk, and efforts to accommodate the natural role of fire in these ecosystems. The LFDB is updated annually and is being expanded back in time to permit a more thorough analysis of long‐term trends in Canadian fire activity.