Monitoring Canadian wildfires’ effect on N.E. air quality
About 40 wildfires burning out of control across canada have already triggered air quality alerts in Minnesota and Wisconsin as smoke from the fires wafts southward in scenes reminiscent of last summer’s thick haze that enveloped the northeast and other parts of the United States.
but is this a harbinger of what’s to come for new Englanders? could we see a repeat of summer 2023 where weeks of stagnant, dangerous air transformed our summer days into eerie orange skies?
More than 140 wildfires are currently burning across canada, 40 of which are considered “out of control,” according to the canadian interagency forest fire centre. the vast majority are in the western provinces (british columbia, Alberta, and Saskatchewan). Massive wildfires burning in Quebec were the main source of smoke in the northeast last summer and currently there are three active fires in Quebec and two in Ontario, but all are deemed “under control.”
“the long-wave pattern is not as favorable yet for wildfire smoke to reach new England, especially with precipitation coming tomorrow,” said meteorologist Matthew clay, of the national Weather Service in burlington, vt. “rain does a good job getting the particles out of the atmosphere, so we shouldn’t see impacts over the next few days.
“Depending on how the pattern sets up over the next few weeks, perhaps it can change,” he added.
Winds pushed a band of heavy smoke south from fires burning in british columbia, prompting officials in Minnesota to issue an air quality alert.
How bad will Canada’s wildfire season be this year?
harjit Sajjan, canada’s emergency preparedness minister, warned back in March that this year’s wildfire season will be worse than the record-breaking season of 2023, especially with climate change fueling hotter weather and escalating fire dangers.
for one, drought conditions in canada have again set the stage for an active wildfire season, although not likely at last year’s blistering pace, according to experts.
Snow cover was minimal or absent across much of canada this past winter, followed by mixed precipitation patterns in the spring. in eastern canada, spring rainfall provided some relief from drought conditions as it did in southern portions of the prairie provinces, located in central canada, which saw some improvement.
“Although this benefits agriculture more than forests, the moisture increase will help reduce the number or size of grass or brush fires in these regions,” said richard carr, wildland fire research analyst with the canadian forest Service.
Out west is where the worst drought conditions have persisted. According to the canadian Drought Monitor, some areas in western canada are in the grips of exceptional drought, the highest category on the scale — hence that’s where the most active wildfires are burning now.
“Drought is intense in northeastern british columbia, northwestern Alberta, and the southern northwest territories,” carr said, adding that the drought’s severity worsened over winter along the central Saskatchewan and Manitoba border.
‘Zombie’ fires through the winter
to make matters worse, more fires than ever smoldered through the winter after having “never fully dampened or extinguished from minimal snowpack” in areas with the most intense drought levels in canada, said Daniel l. Swain, a climate scientist with UclA’s institute of the Environment & Sustainability.
those drought-stricken areas included northern british columbia, where 90 fires continued to burn, and Alberta, where 55-60 blazes smoldered in deep organic material such as peat.
the average number of these “zombie” or “holdover” fires is closer to 5-10 in both provinces. but the high number of these fires has raised fears that many may flare up again this season, and the excessive heat and dryness could stoke the blazes. As of Monday, there were 50 active fires in british columbia and 46 in Alberta.
“there are more fires burning on this date versus the same date from last year. Most are from the legacy of last year where the landscape hasn’t recovered from exceptionally dry and hot conditions,” Swain said.
natural resources canada expects above-average fire potential this remaining spring and summer, mainly in western canada.
Above-average temperatures and near- to below-normal rainfall are predicted to continue across much of canada in May — which is likely to continue fueling fire activity across a large swath extending from british columbia to the northwest territories and northwestern Manitoba in June, with the canadian Wildland fire information System predicting an “extreme” fire severity rating across much of this zone. Most of Alberta and Saskatchewan will also face higher fire dangers compared to normal.
What are the implications for the Northeast?
“Air quality would be worst and health impacts greatest with smoke from eastern canada, since concentrations at the ground level may be high,” carr explained.
And right now the fire severity rating is predicted to be moderate across much of Quebec and parts of Ontario, regions closer to the northeastern United States. As of Monday, three active but controlled fires were reported in Quebec and only two in Ontario, according to canada fire officials.
two scenarios could usher in smoke lower in the atmosphere, should more fires ignite in eastern canada, with the potential to create dangerous air quality. if an area of high pressure sits over the hudson bay in canada, then that could send smoky air southward.
Also, storm systems swirling near the Atlantic coast could draw smoky air southward, especially if they’re persistent over a few days.
And although “the drought is not as severe in the eastern [parts of canada], there are predictions for another unusually hot summer,” UclA’s Swain said, noting that it’s not just smoke from canada we need to worry about. “the eastern US can see major smoke episodes with wildfires stretching from Mexico to canada, contributions from three different countries.”
Smoke from wildfires burning in western canada can also reach the eastern United States. typically, though, smoke originating from a distant source would remain higher in the atmosphere with fewer consequences on air quality. When smoke is in the upper atmosphere, it can cause vivid red sunrises and sunsets.