Chinchaga ignites. By September, it would become the largest single fire on record in North America.

The Chinchaga fire of 1950, often dubbed the “Great Smoke Pall,” was one of the largest recorded wildfires in North American history. Igniting in northeastern British Columbia and quickly spreading into northwestern Alberta, the blaze consumed an estimated 1.4 to 1.7 million hectares (approximately 3.5 to 4.2 million acres) of boreal forest. Unlike many modern wildfires, the Chinchaga fire wasn’t heavily suppressed—largely because it occurred in remote, sparsely populated areas. What made this fire especially notable was its impact on atmospheric conditions: the massive amount of smoke it produced drifted across North America and even reached Europe, dimming skies and altering sunlight levels in regions thousands of kilometers away. This event spurred early scientific interest in wildfire smoke transport and its broader environmental effects.