Canadian Wildfires Came From Rotten Luck, Not Climate Change

Extreme weather results from a combination of random factors in a complicated system

By Clifford Mass. He is a professor of atmosphere sciences at the University of Washington. Excerpts:

"Headlines suggested that the primary culprit was climate change, but these claims are inconsistent with peer-reviewed science, the observational record and our growing understanding of the meteorology associated with wildfire events."

"An unusual atmospheric circulation resulted in wildfire ignition and rapid growth, with an intense low-pressure area pushing undiluted smoke into the New York area. Global warming was only a minor player in this event.

The recent wildfires occurred in the boreal forests of northern Quebec. Fire isn’t rare in that region. The ecology of these forests relies on fire for the release of seeds and forest health. Many of the major boreal fires occur during a narrow temporal window from mid-April through early June, just after the winter snow has melted and before grasses and other small plants grow, reducing flammability. During this short window, the dead vegetation from the previous year can dry out sufficiently to burn if there is an ignition source such as lightning or errant human activity."

"Many of the great Quebec fires have occurred during the spring"

"Large boreal forest fires during the spring in Canada are neither unusual nor a sign of climate change."

"The weather prior to the warm spell wasn’t unusually dry, with the Canadian drought monitor showing normal moisture conditions and temperatures near or below normal."

"It was the perfect storm for smoke in New York, with several independent elements occurring in exactly the right sequence. It’s difficult to find any plausible evidence for a significant climate-change connection to the recent New York smoke event. The preceding weather conditions over Quebec for the months prior to the wildfire event were near normal. There is no evidence that the strong high pressure over southern Canada that produced the warming was associated with climate change"

"there is a deep literature in the peer-reviewed research that demonstrates no amplification of high- and low-pressure areas with a warming planet."

"The number of wildfires in Quebec is decreasing; there is no upward trend in area burned, which would be expected if global warming was dominant."