It’s not officially summer yet in the Northern Hemisphere. But the extremes are already there.
Fires are burning across Canada, blanketing parts of the eastern United States in choking, orange-gray smoke. Puerto Rico is under a severe heat alert, as other parts of the world have been recently. Earth’s oceans have been warming at an alarming rate.
Human-caused climate change is the force behind such extremes. Although there is no concrete research yet to attribute this week’s events to global warming, the science is unequivocal that global warming significantly increases the chances of serious wildfires and heat waves like those affecting large parts of North America today.
Now comes the global weather pattern known as El Niño, which can raise temperatures and set heat records. On Thursday morning, scientists announced its arrival.
Taken together, this week’s extremes offer one clear conclusion: the world’s richest continent remains unprepared for the dangers of the not-so-distant future. A sign of that came Wednesday when Canada’s prime minister, Justin Trudeau, said his government may soon create a disaster response agency to “make sure we’re doing everything we can to predict, protect and act before more of these events come.”
The recent fires have also shattered the idea that some places are relatively safe from the worst dangers of climate change because they are not near the equator or far from the sea. Almost without warning, smoke from distant fires turned everyday life upside down.
So much smoke from the fire pushed across the border that schools in Buffalo canceled outdoor activities. Detroit was suffocated by a toxic haze. Flights were suspended at airports in the northeast.
“Wildfires are no longer just a problem for people living in fire-prone forest areas,” said Alexandra Page Fisher, a professor who studies fire adaptation strategies at the University of Michigan.
In the United States, more and more people are already living with smoke from wildfires. A 2022 study by Stanford researchers found that the number of people exposed to toxic pollution from wildfires at least one day a year increased 27-fold between 2006 and 2020.
The two countries experiencing these extremes, the United States and Canada, are major producers of oil and gas, which, when burned, produce greenhouse gases that have significantly warmed the Earth’s atmosphere. The average global temperature today is more than 1.1 degrees Celsius (2 degrees Fahrenheit) higher than in the pre-industrial era.
Park Williams, a geologist at the University of California, Los Angeles, pointed out that eastern Canada and northern Alberta are actually projected to become wetter in the coming years, according to climate models. But this year that was not the case. It has been an unusually dry year across much of Canada. Then came the heat.
The boreal forests of western Canada offered ready fuel. The trees and grass of eastern Canada turned to drone. “Under warmer temperatures, those dry years will cause things to dry out and become flammable faster than they would otherwise,” said Dr. Williams.
By Wednesday, more than 400 fires were burning from west to east in Canada, more than half of which were out of control.
Other parts of the world felt the heat this year. Vietnam broke a heat record in May, with temperatures soaring above 44 degrees Celsius, or 111 Fahrenheit. China breaks heat records in more than 100 weather stations in April. The boreal forests of Siberia are also burning.
As in the North American boreal forests, climate change is making the wildfire season longer and more severe in Siberia. It also increased lightning ignitions, said Brendan Rogers, a boreal wildfire expert at the Woodwell Climate Research Center. Of course, there are different conditions in different years, he said in an email, but “the common denominator is warm/hot and dry conditions that encourage ecosystems to burn.”
Where does all that excess heat in the atmosphere go? Much of it is absorbed by the oceans, which is why ocean temperatures have been steadily rising for the past few decades, reaching records in 2022.
But this spring something strange happened. Scientists announced with unusual alarm that ocean temperatures were the warmest in 40 years.
Scientists have not determined the reason, although some say the increase could signal the arrival of El Niño. That weather pattern, which usually lasts several years, brings warmth to the surface of the eastern Pacific Ocean. For the past few years, we’ve been living with its cooler cousin, La Niña.
Jeff Berardelli, a meteorologist at WFLA, a television station in Tampa Bay, Fla., warned on Twitter about the double whammy of El Niño in a world already warming due to climate change. “We should expect a stunning year of global extremes“, he wrote.