Michigan weather may save our state from our own wildfire season | Opinion

Welcome to “fire season.”

Even if we don’t see flames where we live, across much of the U.S. and Canada, in any given year, we are likely to see smoke and breathe polluted air from fires more than a thousand miles away.

Cities are burning with regularity: Los Angeles, Santa Rosa and Paradise, California; Louisville, Colorado; Lahaina, Hawaii; Jasper, Alberta.

West Michigan is currently under an air quality warning from Canadian wildfire smoke. For the last few years, the smoke has regularly obscured the sun and fouled the air across the eastern U.S. and Canada.

Michiganders have been living with wildfire smoke. But can a warming climate bring wildfires to Michigan?

The easy answer is that yes, a warmer climate can increase the risk of fire in Michigan.

A more useful answer, however, is not easy. Understanding the likelihood of more wildfires in Michigan requires a framework for thinking about how a warming climate’s may influence wildfires in Michigan.

Fuel, heat, oxygen, ignition

First, there are some overarching ideas to introduce.

The ingredients of fire are often listed as fuel, heat and oxygen, and implicitly, a source of ignition. The way a warming climate influences these ingredients most strongly is by changing the characteristics of the fuel in wildfires, the fuels we think of first are grasses, brush and trees. A warming climate can make these fuels wetter or drier, and that decreases or increases the risk of wildfire.

Another overarching idea is how we manage our landscape. The amounts of grasses, shrubs and trees are often determined by decisions people. Even more directly related are decisions about where we build our houses and towns, and how we manage the interface between our towns and natural, unbuilt spaces.

Or decisions about how we manage fire, which is a naturally occurring part of the landscape. Do we suppress all fires? Do we practice controlled burns? Do we use fire to clear land?

Our landscape management decisions are often more important to wildfires than a warming climate. That is good news, because it means we also have a powerful method to limit and protect ourselves from wildfires.

Rainy Michigan summers suppress fire risk, increase flood risk

If we consider Michigan and the states in the Great Lakes region, the most definitive aspect of climate change is that it is warming.

A warming climate can be wetter, drier, or bounce back and forth between the two.

From a fire perspective, in Michigan we are, at first blush, fortunate. There is a large supply of water vapor to the Great Lakes region, which means we get a lot of rain. This reduces fire risk, but at the cost of increased flooding. 

However, we live in a region that does experience drought. These are times that the moisture supply to the region is disrupted. Because it is warmer now than during the droughts we experienced in the past, fuels, especially grasses and brush, dry out more quickly. Plus, in the warmer, wetter periods, the grasses and brush grew more quickly, leading to more potential fuel.

Increased, dry fuels increases fire risk. This risk is realized in fires such as those in Jackson County in April of 2024.

So, episodically, we expect increased risk of wildfire as the climate warms. And, of course, extended drought would lead to increased risk in forested lands.

Michigan is probably safe from serious wildfires

In the past decade, we have seen both more precipitation, and extreme precipitation.

This increase in precipitation likely contributes to a decrease of wildfires in North Central Hardwood Forests, an ecological region that includes some southern portions of Michigan,

documented in a scientific paper by researcher Victoria Donovan and others.  

But the wetter weather of the past decade is not guaranteed for our future. It is plausible, if not probable, that as warming continues, we will have more evaporation than precipitation, which would dry grasses and brush and increase fire risk.

Still, it is not likely that Michigan will have fire seasons such as those experienced in western Canada and the western United States.

But Canadian wildfires will continue

The western U.S. and Canada has a wet-season/dry-season climate, in which winters are usually wet and summers are often very dry. Those regions have a history of multi-year droughts, and there has always been a fire season.

As it gets warmer, the fuels ― dry trees, grasses and brush ― in the summer are increasing. We can document increases in fires in western North America that are related to the warming climate, and there is little we can do in Michigan to avoid the smoke and air pollution from these distant fires.

But Michigan does not have that natural wet-season/dry-season climate of the West Coast; we normally get precipitation all year around, and in recent years we have been getting more precipitation. So, it is unlikely we’ll slip into a West Coast fire regime anytime soon.

There are, however, parts of the Great Lakes region, including the Upper Peninsula, where it’s gotten warmer than in other parts of the region, and in which the precipitation increases are smaller. This is a yellow flag to be alert to potentially increasing fire risk.

What about those Canadian fires that seem to regularly bring haze and smoke to Michigan? Large fires in eastern Canada have happened before. We can say that the size and duration of the Canadian fires in 2023 were influenced by the warmer and warming climate. As the climate is still warming, we can expect this to continue.

Pay attention to precipitation

Though wildfire is a threat in Michigan, and a warming climate can, at least episodically, increase its risk, we are fortunate to have abundant water and moisture.

Also, in populous regions, there are usually diligent efforts to prevent and fight fires. Climate scenarios that consider drought and fire are part of responsible planning. Management of the landscape makes sense irrespective of warming.

Looking beyond 10, 20 or 30 years, it is essential to pay attention to changes in the balance of precipitation and evaporation, because the more it warms, the greater the fire risk.

Richard B. Rood is professor emeritus of climate and space sciences and engineering at the University of Michigan, Ann Arbor. Submit a letter to the editor at freep.com/letters, and we may publish it online and in print.  

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