Canada, which suffered its worst wildfire season ever in 2023, is now covered in dozens of wildfires, sending smoke blowing across the northern U.S.
The fires are driving thousands of Canadians from their homes in British Columbia and the neighboring province of Alberta. The Canadian government warns that this year’s conditions might mean a greater wildfire risk to come.
As of Monday, Canada had 145 active fires burning, according to the Canadian Interagency Forest Fire Centre.
Environment Canada had predicted challenging weather conditions with an impending difficult wildfire season for the country thanks to a warm winter with little snow, coupled with droughts in many regions.
Last year was the hottest on record globally. This was primarily due to carbon emissions and other climate change factors, but it was also intensified by the natural El Niño weather pattern.
The air quality caused by smoke from the fires postponed sporting events, driving people inside, and it even had some farmers concerned that the smoke delayed their corn crop’s maturation. Currently, smoke from Canadian wildfires have reached unhealthy levels from Montana to Wisconsin, and it’s spreading south and east into the Midwest and Great Lakes regions.
Is smoke affecting crop yields?
Over the past few years, levels of smoke in the air during summer and fall in the Corn Belt have become commonplace as wildfires in the Western U.S. and Canada have increased in frequency and intensity.
Information from Pioneer Hi-Bred International shows that low growth periods in June 2022 correspond to the same times that heavy wildfire smoke over Ohio and Indiana fueled low solar radiation that corn depends on to grow.
However, the greatest potential impact of these wildfires on crops has been the decreased sunlight that reaches the crops due to smoke. Corn, in particular, is susceptible to reduced yields and standability if the plants remobilize carbohydrates from the stalk to make up for a deficit in photosynthesis, opening up the stalks for stalk rot pathogens.
Pioneer notes that while wildfire smoke does contain pollutants that can be harmful to crops, but it’s not known whether smoke increases the ground-level concentration of the compounds enough to have an impact.
Experts also indicate that the lower temperatures caused by wildfire smoke aren’t always detrimental to crops. The reduced solar radiation due to the smoke can help slow the loss of moisture from the soil into the atmosphere.
However, while wildfire smoke may have contributed indirectly to late maturations in previous years, Kyle Poling, a field agronomist at Pioneer told The Guardian in November that other factors were at play, too.
Mexico also experiences wildfires, blackouts, and drought
“As Mexico entered peak fire season in March 2024, dry and warm conditions helped fuel the flames of more than 100 active blazes across the country,” said NASA.
Now, the country is fighting 159 active wildfires alongside the country’s second heat wave in two years. The heat wave sweeping the country has caused Mexico’s national weather service to issue an alert to 12 states, which may experience temperatures over 113 degrees Fahrenheit.
The heat wave has also impacted the country’s power system, prompting the country’s grid operator to declare the system in a state of emergency last week. Meanwhile, drought has caused 20 million people in the country to live with intermittent water supplies in recent months due to limited rainfall.
Is climate change the reason?
Wildfires in North America have gotten considerably worse in recent years, and research continues to amp up to figure out why.
Over the past 40 years, the area burned by wildfires in the U.S. has quadrupled to over 8 million acres annually. In Canada, the 2023 wildfire season saw over 38 million acres burned.
While fire is a normal part of the ecosystem, some sources say that climate change is contributing to more wildfires, with higher temperatures and lower rainfall occurring during fire season, increased length in fire seasons, and earlier snowmelt.
Meanwhile, many also point to mismanaged forests and policies that they believe are contributing to intense and more frequent wildfires with increased fuel caused by decades of fire suppression and a hotter, drier climate.
Wildfires are triggered by both natural and human causes. In the U.S., fires caused by people have resulted in more damage in recent years. However, lightning-ignited fires have historically caused more damage in the Western U.S.
This year’s fires in Canada are believed to have smoldered underground throughout the winter, with low and early-melting snowpack failing to extinguish them.