Smoke from a Distant Fire: Canada’s Wildfires Make Impact in Â鶹´«Ã½
Fri, 06/09/2023 - 09:21am | By: Dr. Clay Tucker
Perhaps, like me, in the past few days you have made the long trek up the tallest building in Hattiesburg, the 10-story Johnson Science Tower on The University of Southern Mississippi (Â鶹´«Ã½) campus here. And perhaps you have seen the gray haze amidst the hills of southern Mississippi this week as well. The wildfires currently burning in eastern Canada have put a great amount of smoke into the sky, and regional weather patterns have brought some of that smoke as far as to the Gulf Coast. This is not an uncommon feat for wildfires. In fact, just a month ago my colleague Dr. Andy Reese and I were discussing how these phenomena can occur.
Dr. Reese is a palynologist, a person who studies the legacy of pollen buried in sediments, and often these pollen are accompanied by microscopic charcoal. Like pollen, microcharcoal is light and can travel dozens or even hundreds of miles. You have probably seen the embers from a bonfire gently floating up on a cold night. Aided by the rising heat of the fire, these particles remain suspended by wind and can make it thousands of feet into the atmosphere where wind can travel more than 200 miles per hour.
In the current state of weather in eastern North America, upper-level wind patterns like those described above are flowing from north to south, a non-typical pattern for this region in the summer. Additionally, much of the Southern U.S. is experiencing high pressure at the surface currently. In other words, air from the top of the atmosphere is flowing downwards to the surface, bringing any smoke particles with it. Remember that bonfire we talked about before? I’m sure you’ve sat next to one on a windy night and it was difficult to breathe at times with all that smoke floating around. Smoke from distant wildfires can have a similar effect.
Fear not – the weather that is happening right now won’t stick around forever. In fact, the north-to-south weather pattern we’re currently facing in eastern North America will shift to its regularly scheduled west-to-east pattern soon. The much bigger question: How often can we expect this in the future? And will Canada wildfire seasons run longer into the summer than usual? The answer from climatologists like me is simple: Yes, humans have an impact on large atmospheric systems. Statistically, we have modified the dice we roll for weather phenomena like Canada’s wildfires. Before humans, Earth had two normal six-sided dice numbered one through six. But as we change concentrations of CO2 and modify our world, we change one of the fives on the dice to extra six, increasing our chances when Earth rolls her dice on extreme weather.
Dr. Clay Tucker is an assistant professor in The University of Â鶹´«Ã½ Geography Program.