Will Wildfires Like Canada’s Become the New Normal?

Advertisement

Canada’s devastating fires and toxic smoke might not recur every year, but the heat from climate change increases the risks of a wide range of disasters.

By Somini Sengupta

Reporting from New York City, where the fine particle pollution level peaked at 868 micrograms per cubic meter on Wednesday.

With so much toxic wildfire smoke moving across the Canadian border and upending life across the Eastern United States, it raises a troubling question: Will there be more of this in the years ahead, and if so, what can be done about it?

First, let’s take a step back. Global average temperatures have increased because of the unchecked burning of coal, oil and gas for 150 years. That has created the conditions for more frequent and intense heat waves.

That extra heat in the atmosphere has created a greater likelihood of extreme, sometimes catastrophic, weather all over the world. While that doesn’t mean the same extremes in the same places all the time, certain places are more susceptible to certain disasters, by virtue of geography. Australia could see more intense drought. Low-lying islands are projected to experience higher storm surges as sea levels rise.

In places that become hot and dry, wildfires can become more prevalent or intense.

The unifying fact is that more heat is the new normal.

The best way to reduce the risk of higher temperatures in the future, scientists say, is to reduce the burning of fossil fuels. There are also many ways to adapt to hotter weather and its hazards.

Eastern Canada, which erupted in extraordinary blazes, is projected to be wetter, on average, especially in winter. The projections are less clear for summers, when soil moisture is important for creating fire conditions, according to Park Williams, a climate scientist at the University of California, Los Angeles.

Eastern North America is also projected to become much hotter, with many more days when the maximum temperature will climb above 35 degrees Celsius, or 95 degrees Fahrenheit, according to the Intergovernmental Panel on Climate Change.

So, in a dry year, the extra heat is likely to aggravate fire risks. That’s what happened this year in parts of Quebec. Snow melted early. Spring was unusually dry. Trees turned to tinder.

The Northeastern United States is also projected to be wetter in the coming years. But as Ellen L. Mecray, the eastern regional climate services director at the National Oceanic and Atmospheric Administration, said, “We have also been experiencing seasonal droughts more often, in part due to increasing temperatures, changing precipitation patterns, and loss of soil moisture.”

As for air pollution, she said, wildfire smoke from the West, even dust across the Sahara, can travel across the globe to the United States, bringing with it hazardous particulate matter, according to the latest National Climate Assessment, published in 2018.

“From a human health perspective, we are concerned about the frequency and duration of such smoke events,” said Lesley-Ann Dupigny-Giroux, a climate scientist at the University of Vermont who led the report’s Northeastern U.S. chapter.

First, heat. By 2035, according to the National Climate Assessment, average temperatures are projected to increase by more than 2 degrees Celsius (3.6 degrees Fahrenheit) from the preindustrial era. That’s larger and earlier than the global average.

Rising average temperatures increase the chances of more frequent and intense heat waves. That’s especially risky for people who work outdoors or who cannot afford air-conditioning.

Second, for coastal areas of the Northeast, there’s the risk of sea level rise. That means flooding dangers affecting millions of people. Cities have long been warned to prepare by improving drainage, opening up floodplains, planting shade trees and encouraging better insulation for buildings.

In the Southeastern United States, climate models indicate “increased fire risk and a longer fire season.” Fires ignited by lightning (as opposed to humans) are projected to increase by at least 30 percent by 2060, the National Climate Assessment said.

In Western states, the wildfire season is already longer because of higher temperatures, drought and earlier snowmelt. By midcentury, the assessment concluded, the area burned there could at least double.

California could get a break this year because of a wet winter and spring. But not necessarily the Pacific Northwest. Dr. Williams, the climate scientist, said that “if a major heat wave occurs in that region this summer, I expect that fuels will be plenty dry to sustain large fires.”

Most fires in Quebec appear to have been started by lightning. Elsewhere, such as in the Western United States, human carelessness and the mismanagement of aging power lines have led to catastrophic fires. Both are fixable problems.

Fire experts say that the mechanical thinning of forests, as well as “prescribed burns” — the intentional burning of underbrush — can also reduce the spread of wildfires, but with risks.

Some things that protect people from heat also help protect from wildfire smoke. Leaky, poorly insulated buildings are as hazardous on hot days as they are in smoke.

The most efficient way to keep temperatures from rising further is to reduce the combustion of fossil fuels. They are the drivers of heat and its hazards.

Somini Sengupta is The Times’s international climate correspondent. She has also covered the Middle East, West Africa and South Asia and is the author of the book, “The End of Karma: Hope and Fury Among India’s Young.” More about Somini Sengupta

Advertisement