Converging and diverging burn rates in North American boreal forests from the Little Ice Age to the present

Warning This article contains terms, descriptions, and opinions used for historical context that may be culturally sensitive some readers. Background Understanding drivers of boreal forest dynamics supports adaptation strategies in the climate change. Aims We aimed to understand how burn rates varied since early 1700s North American forests. Methods 16 fire-history study sites distributed across such forests investigated variation period spanning 1700–1990. These were benchmarked against recent estimated modern 1980–2020 using various data sources. Key results Burn during most showed a declining trend, particularly mid 1900s. Compared period, less variable lower sites. Mean presented divergent trends among eastern versus northwestern sites, with increasing mean Conclusions The synchronicity suggests large spatial patterns atmospheric conditions drove addition regional changes land use like fire exclusion suppression. Implications Low Canadian continue unless change overrides capacity suppress fire.