When I first descended upon Maine to ruin the proud broadcast tradition of WCSH-TV one skinny suit at a time, wildfire smoke wasn’t a thing I had to forecast. That was 2010 (and this is what I looked like. Don’t @ me). In the last few years, however, it’s become an accepted part of summer in the state. So what’s going on here?

Our recent bout of smoke on Tuesday and Wednesday comes from a wildfire in western Ontario. And that’s often the case for Maine – our smoke comes from Canada, or, with the right jet stream position, the American West. It IS all about the jet stream, the current of air around 35,000 feet that generally travels west to east and carries our weather with it. But it also carries particulate matter, like smoke. 

That’s the short-term explanation. The longer-term explanation is more complicated. According to NASA, extreme wildfire activity has more than doubled worldwide over the past 20 years (More in-depth, nerdier reading here). So it’s not just your imagination: This really is happening more often than in the past.

Climate change is a significant driver of this increase. In fact,  a 2021 study by NOAA found climate is the main cause of increased wildfires in the West. More extreme droughts, warmer overnight temperatures and earlier melting of snowpack, which extends the wildfire season, are all mechanisms at work here. These are pretty easy connections to understand as droughts dry out forest fuels while warmer temperatures support longer burns and increase wildfire acreage. There are secondary climate change tie-ins that are a bit more complicated, such as warmer temperatures allowing for the proliferation of invasive species that change forests. One example is the bark beetle that no longer encounters the winter cold spells needed to temper the population and as a result has killed more than 100,000 square miles of trees in the West, priming those forests for burns.

I’ve always believed it very important to be scientifically accurate and complete, so let’s talk about Chapter 2 of this story: It’s not just climate change that has given us smokier skies here in Maine.

Forest management also plays a role, particularly in Canada. This is a complicated topic, but years of aggressive fire suppression unintentionally stacked forests with huge dry fuel loads, coupled with fewer prescribed burns and commercial logging replanting tactics that favored highly flammable tree species, lead to more dangerous wildfire conditions in their forests. And once a large fire breaks out there are huge swaths of Canada’s northern forests that are completely inaccessible, making battling the fires all but impossible.

So climate change is the main driver, but forest management also plays a role. The bad news: That means more smoky days in Maine’s near future. The good news: We, as humans, can help correct both problems for a healthier, cleaner long-term future.

Keith Carson, an award-winning Maine meteorologist previously of News Center Maine and The Weather Channel, is the director of environment & science communications for the Maine Conservation Voters nonprofit.