Think it’s hot now? Michigan’s 90° days could quadruple in 20 years


All 83 counties in Michigan are getting hotter, and a report released Tuesday predicts it will only get worse, as the number of days with heat indexes over 90 degrees will quadruple in the next 20 years.

The report from the Union of Concerned Scientists, a Massachusetts-based nonprofit science advocacy group, predicts extreme temperatures will soar nationwide if nothing is done to curb climate change.

The impact could be devastating for Michigan: destroyed crops, an increase in disease-bearing insects, dangerous conditions for outdoor workers, and rising death rates, according to the report.

Related: Climate change could bring woe to Michigan’s lakes, farms, forests
Opinion: Climate change drives shifts between high, low Great Lakes water levels

Between 1971 and 2000, Michigan averaged eight days a year with heat indexes above 90 degrees Fahrenheit. By midcentury, that will rise to 34 days per year if no action is taken to stem greenhouse gases linked to climate change, the report claims.

Cities in southern Michigan –  Benton Harbor, Kalamazoo and Monroe –  would have the most days with 100 degree-plus heat indexes, a measure that factors humidity into temperature to gauge how weather feels. 

But even Mackinac County, in the eastern Upper Peninsula, would feel the heat, as the average number of days with heat indexes over 90 increases to 12 per year from none, while they jump to 27 from four in Roscommon County in northern Michigan.

“If it does get that warm, it is going to have an impact on health, and you might have to start working at different times of the day,” said Tom Miedema, president of a turf farming company in Ottawa County.

“You’re going to have to adjust for some of those things.”

The report joins a growing number of studies that predicts a host of problems, from infrastructure deterioration to lake algae blooms, in Michigan if temperatures increase an average 2 degrees over the next 40 years.

Jennifer Morse, the medical director for the Central Michigan District Health Department, oversees 12 counties including Roscommon. She worries that rising heat would hurt a variety of demographics.

Related: Surging Great Lakes water levels shrink beaches, flood docks in Michigan
Related: Michigan shrinks credits for rooftop solar, clouding industry’s future

“When we have high heat index days, a big population that really suffers is our elderly population,” said Morse. “They are just very susceptible to heat changes.”

The report warns that communities of color, such as Benton Harbor, are particularly vulnerable to extreme heat because of limited access to cooling or healthcare centers. 

The report parallels the Paris Agreement, a United Nations goal to limit the global temperature increase this century to well below 3.6 degrees Fahrenheit, and predicts scenarios if there is “slow” or “rapid” actions to limit emissions.

Without any effort to reduce global warming, the Union of Concerned Scientists predicts that 8.7 million people – nearly 90 percent of Michigan’s population – would experience a heat index of 100 degrees for a month or more per year by the end of the century.

The extreme heat would be avoided with rapid action, and limited with slow action: an average of six days a year in Michigan with an average heat index above 100 degrees and 26 days above 90 degrees by midcentury. 

Nationwide, one-third of the United States would experience “off-the-charts” heat by the late century if nothing is done. “Off-the-charts” conditions refer to when the temperature is so high that it exceeds the National Weather Service’s heat index calculations.

“For the nation, extreme heat is projected to increasingly put people at risk – that is going to be the case across the country,” said Rachel Licker, a senior climate scientist at the Union of Concerned Scientists and a co-author on the report. 

“This is something that is really going to change the daily life for many residents in the United States.”

Urban areas have a “unique vulnerability,” due to a phenomenon known as the heat island effect, said Licker. And in Michigan, a state with over 51,000 farms, agricultural workers are especially at risk.

“What we found was that the conditions that we could be seeing in the future are conditions that could be dangerous to outdoor workers,” said Licker. “Those people are uniquely vulnerable to extreme heat.”

A similar report by the Michigan Department of Health and Human Services and the University of Michigan predicts that extreme heat mortality in Michigan will increase from 33 to 240 deaths annually by midcentury, if nothing is done to combat climate change. The report includes any death prompted by extreme heat in the mortality rate, not just those from heatstroke.

“We were considering all natural cause mortalities, not just heat stroke in that estimate,” said Carina Gronlund, an environmental epidemiologist and author on the University of Michigan report. “It’s not necessarily emergency room visits with heat exhaustion or heatstroke on the [patient] record.”

Along with outdoor workers, children, the elderly, low-income communities and those with pre-existing health conditions, such as respiratory or cardiovascular illness, are at a greater risk for heat-related death.

This report also suggests that without climate change action, the number of emergency room visits related to heat health issues will increase from 1,200 to 7,800.

The projected cost as a result of rising mortality and ER visits is more than $290 million.

To curb the effects of the climbing heat rates, the global warming average would need to be limited to 3.6 degrees Fahrenheit, per the “rapid” action plan. If done so successfully, by late century about 115 million less people would experience over a week of “off-the-charts” heat.

“If we don’t take action to reduce global warming emissions now, we’re really setting ourselves up for a dramatically different future,” Licker said. “And it’s one that would have implications for health, for many economic sectors, and our day-to-day activities.”

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Tue, 07/16/2019 - 8:57am

Excellent coverage of one of the aspects of the climate emergency we are in. The people need to know the truth however unpleasant it is, in order to address the solutions. The media needs to keep telling it in a comprehensive manner over and over. Keep reminding us to get off our duffs and get to work. Mobilization on the WW II level is what is needed if we are going to lower the carbon level before it gets beyond our ability to do anything about it.

Tue, 07/16/2019 - 10:10am

The US has lead the world in progress to this goal because of switching from coal to Nat Gas in spite of bailing on the Paris Treaty. If the US goes to 0 it still makes an insignificant change, how do you propose to force other nations to get in line? Is that what you meant by WW2?

James tomlinson
Wed, 07/17/2019 - 11:47am

Lead by example.

Roger D
Tue, 07/16/2019 - 9:32am

Good commentary as usual Bridge. I would like to see expanded commentary on the pollution of our Michigan Land, Lakes and Rivers, and Air.

Tue, 07/16/2019 - 9:36am

If the people were interested in the truth, they wouldn't have elected Trump who is much more focused on dismantling Obama and making any progressive changes. There is so much we can do that would be relatively painless but no leadership to guide the population to even making little planting trees.

Tue, 07/16/2019 - 10:14am

I see Michigan as a safe zone from raging hurricanes, rising sea levels, oppressive heat and disappearing drinking water. The wealthy will gravitate to this area as the country becomes less hospital to human life. We have a huge reserve of fresh water and a buffer from hurricane damage. With Trump working to ruin any protection from this future climate change reality many will find themselves without the the wealth to migrate to habitable areas of the United States. Michigan will be a temporary refuge from the coming storm!

Tue, 07/16/2019 - 2:39pm

This has to be the most moronic comment I'll read today.

Richard Barron
Tue, 07/16/2019 - 10:23am

This article is fine warning of one serious aspect of planetary heating but it is obviously not a Michigan problem as much as a global problem. This country, that is to say the Congress, needs to take the lead in the dramatic and immediate reduction in our national greenhouse gas emissions to check climate change. The US House of Representatives is currently considering a bi-partisan bill that will seriously attack this problem: the Energy Independence and Carbon Dividend Act, HR 763. . Michigan Representatives Lawrence, Levin & Kildee are co-sponsors.
This bill will make American fossil fuel producers pay for each ton of CO2 they emit into our air. This fee will slowly increase each year. This fee will be transmitted to a US Treasury trust fund and 100% of the net revenue will be sent, pro rata, to every American household, monthly. This monthly income could be used to pay for the presumably higher energy costs or for any purpose. Economists have calculated that, except for the highest income people, the amount of the dividend will exceed the higher cost of fossil fuel energy. They are nearly unanimous that a fee on carbon based energy sources is the best and most efficient means of reducing society's use of polluting fossil fuels. When prices go up, people buy less or switch to cheaper substitutes.
This universal dividend will expand our economy and create additional jobs. This will be amplified by the expansion of employment in the clean renewable energy field. Finally, there will be a dramatic improvement in our public health due to improved air quality.
If, after studying this bill, you agree that this is a necessary common sense remedy, citizens should urge their members of Congress, both House & Senate, to support it.

Tue, 07/16/2019 - 10:32am

What are you gonna do dummy? Reverse the polar flip and the solar minimum? Pull your head out of your ass and start telling the truth about what's going on!

Jim tomlinson
Wed, 07/17/2019 - 2:56pm

Find a different forum sonny. Man made climate change is settled science

Big John
Tue, 07/16/2019 - 10:57am

OK, climate change. Read the articles but nowhere is there any reference to what the average individual can do to retard the phenomenon.
We have invested in geothermal heating and cooling, 98% of our electrical needs come from solar panels, our home is insulated to the max, retrofitted with all insulated low E windows,
And our appliances are all energy star rated.
These scare tactic articles are worthless with out including solutions.
I frankly feel we’ve Done our part and then some.

Bigger John
Tue, 07/16/2019 - 11:49am

Your self absorbed comment is worthless and doesn’t offer a plausible solution to the issue. Not everyone can invest in geothermal energy and buy energy star rated appliances. The purpose of this article is to inform and it does so perfectly.

Tue, 07/16/2019 - 12:35pm

It would be interesting to see a Bridge survey of how many people have taken certain actions on their own to combat excessive CO2 use. Actions such as installing LED light bulbs, high efficiency or energy star appliances, additional insulation, green building products, or other energy saving products. What is the gas mileage of the cars people drive and how many miles per year does the average person drive. What have they done to minimize vehicle use and walked or pedaled a bicycle.

And on another item, how many readers does Bridge have, 1%, 2% of Michigan population? We the people can do an awful lot without getting the government involved. We just have to be honest with ourselves and realize that even if we 0 fossil fuels, the production chain of healthy products such as electric vehicles may involve using fossil fuels somewhere in the production and use overall cycle.

Tue, 07/16/2019 - 2:37pm

The climate has been changing long before anything man made. Enough of this scam.

Wed, 07/17/2019 - 3:37pm

Yes it has! The issue isn't the fact that change is happening, it's the RATE of change that is causing problems. I found this to be an excellent visual aide to explain the problem:

Ruth Skelly
Mon, 07/22/2019 - 5:02am

the "man-made" claim only exists is that it has been a man-made HOAX from the beginning. there is NO 'visual aide to explain the problem' . to allege man is that powerful that effects/cause climate charge is beyond ARROGANT. without carbon ALL life, man/animal/plant, will cease to exist. to continue to force the ridiculous ideas of changing lightbulbs will save the planet is insane. predictions made (scare tactics) have come & gone over the years of a man-made crises ALL it has achieved is costs have increased, money flying out of consumers pockets all the while these 'scientists' have enriched themselves. Al Gore being perfect example of the HOAX perpetrated by self-described 'scientists'. Follow the money.

Tue, 07/16/2019 - 3:10pm

Wonder how long this propaganda piece has been sitting in the cue? Must be disappointed that you couldn't release this article in May or June while we were experiencing unseasonable cold and rain. It's 90 in mid-July. Why is that such a surprise and why was nobody screaming about damaging global warming a month ago? Nothing here but oppressive opportunism.

Jim Malewitz
Tue, 07/16/2019 - 3:53pm

Thanks for reading, Billhilly. Sounds like you're confusing climate with weather. Here's an explainer about the difference between the two from the National Oceanic and Atmospheric Administration. And here's a concise NASA explainer about why the vast majority of climate experts agree human activity is warming the earth at an unprecedented rate. 

Here is a list of nearly 200 worldwide scientific organizations agreeing with that position. 

Keep in mind we're talking about changes in average temparatures over the course of years — not day-to-day fluctuations.

This Associated Press article includes a map (generated from federal data) showing that every U.S. county — including all 83 in Michigan — have warmed on average over the past three decades. Average temperatures across much of the Lower Peninsula are now at least 2 degrees Farenheit higher compared to 1988. 

-Jim Malewitz, Bridge Magazine environment reporter 

Kevin Grand
Wed, 07/17/2019 - 6:07am

Mr. Malewitz,

You DO realize that it's hard for people to take you seriously, when the "experts" that you cite have been caught manipulating the data, not just once...but multiple times, in order to promote the theory that you're advocating.

You, along with The Bridge, always fail to cite that troubling detail.

Why is that?

Wed, 07/17/2019 - 12:45pm

Thanks for the thoughtful reply. I respect your journalism just wish there was more critical investigation and analysis of the studies and data used to formulate the conclusions. We know many studies have been found to be fraudulent, many are based on computer modeling, and the historical data used today is often estimated or extrapolated since the level of data gathering in the past was rudimentary or non-existent. It seems those using the climate versus weather argument only do so when the weather doesn't support their position. Regardless of 1,2 or 3 degrees of change, that can reverse in short order (witness the great lake levels or the complete absences of drought in CA), one drive through the beautiful and abundantly lush and wooded Michigan countryside makes it obvious that nature is far less concerned with this faux crisis than those living in concrete jungles.

Unimpressed Con...
Tue, 07/16/2019 - 7:55pm

Another scare story, that follows other scare stories from the radical environmentalists. How many times have we heard these dire predictions, only to see them fail to materialize? The term "climate change" was concocted because global warming was being laughed at and proved to be a joke. Only a few years ago the Climate change gang said the great lakes were drying up, and now they are at "record" levels.

Ruth Skelly
Tue, 07/16/2019 - 8:33pm

longest political hoax in history to bankrupt the country via propaganda BS.

Joseph Verreau
Wed, 07/17/2019 - 7:41am

subj: Implications of heat index (and wind chill, while we are on the subject)

An excellent report on the status of climate change in Michigan. I do have one concern: current usage and references to heat index imply that heat index is merely useful to understand our perception of weather in at that point in time. I think references to heat index and to wind chill, for that matter, need to be much more descriptive of the implied additional hazard level related to elevated heat indexes. I notice on the National Weather Service link that they too minimize the hazardous implications of elevated heat index. It is not merely that it feels like a hotter temperature, the risks to vulnerable members of the population are very real.

Wed, 07/17/2019 - 3:28pm

"The only way to help people avoid fiscal difficulties is to do the hard work of educating them on how to be good financial consumers."

Okay... so what's the plan for that?

This "solution" reminds me of other simplistic answers to complex problems. The addiction problems in America weren't solved by telling people "Just say no to drugs." Unplanned pregnancy and STDs weren't eradicated by abstinence-only sex education. Immigration problems weren't fixed by telling people "just stop coming here."

It would be easier to take this professor seriously if he offered a real solution instead of just jumping to the defense of those getting rich by exploiting the poor. Saying "some unspecified party needs to utilize non-existent resources to teach poor people how to have enough money" isn't actually a plan.

Fri, 07/19/2019 - 9:09am

What if the premise is wrong, and this is just the natural ebb and flow of weather? What could be the consequences, the cost be?
Has anyone at Michigan Environmental Watch, asked those questions or are they so focus on what they want others to do they never consider the other side of anything they talk about? Would they want a government agency to only consider one side of anything they do? Would they want businesses to only look at making a product and never asking what the potential consequences of the product may have? Why should the Michigan Environmental Watch the only one not talking about the consequences of their actions and pronouncements, why they be do differently than they want all others to do?

Fri, 07/19/2019 - 3:09pm

Duane, please educate yourself, thousands I repeat, thousands of reputable scientists have done as you suggest and have reached a consensus opinion.

Sun, 07/21/2019 - 9:39pm

The scientific principle is to be skeptical, it was skeptical physicists that proved Einstein theories. Consensus is the hobgoblin of creative minds, it discourages competition of ideas, it threatens diversity of perspective, its sole function is to stop disagreements and conversations.

My point was/is, that any who promote the idea of community action without the consideration of being wrong and identifying unintended consequences are irresponsible because they are trying to intellectually intimidate the less informed, they risk the loss of opportunities for others without fair consideration.

Science has a long history of having consensus theories and principles over turned by a few outside the consensus, the vast majority of the historic greats in science earn their recognition by proving consensus wrong.

Why are you so fearful of thinking outside of consensus? Why are you trying to intimidate some offering a different perspective? Why aren't you interested in exploring thinking outside of consensus?
My experience has been that by being open to thinking counter to consensus you challenge yourself to think differently, to consider what hasn't been taken seriously [most often because it takes work], and by using a different perspective new ideas, new approaches, new questions worth answering show their value.

Consider questioning consensus much like risk analysis, you know what you want to do but disciplined risk assessment forces you to consider the undesirable 'what ifs'. This approach time and again has proven one of the most effective tools for prevent unplanned, damaging events from happening. I suspect that you support such an approach when the discussion of pipeline #5 is talked about. Why should such a successful approach not be considered when it is applies to the science you support?

Roger D
Sun, 07/21/2019 - 9:21am

The key word is "Could" in my opinion

Sun, 07/21/2019 - 10:08am

Sobering. Communities should be preparing NOW to mitigate the harm from the coming crises. This article, like so many on this topic, outlines the dangers we face and then jumps to “unless we curb emissions and get serious about climate change right now.” That ship has sailed. We are far past the point of staving off some of the most disastrous and harmful effects of climate change. Their is ZERO political will to do anything about it among the powers that be, and reusable straws ain’t gonna stop the disasters ahead. So the focus now must be on working together as communities to be ready to face them. Harm reduction. Planning ahead to be ready to reach the most vulnerable among us and those with the fewest resources. Preparing together to support each other in times of great fear, loss and instability. Not counting on some emergency management agency that has a limited focus, but working together NOW to creatively and compassionately “prep” TOGETHER. The inclination to hunker down individually and stockpile food and arms while staving off neighbors in need is a destructive response that leads to violence and suffering and neglect of the people who need the most help in a crisis: the elderly, the ill, people living with disabilities, people with no economic resources to “prep,” the homeless population, children living in poverty and more. Now is the time to engage in constructive community-wide conversation and decide how we can face coming challenges with dignity and compassion.

Sun, 07/21/2019 - 11:59am

it's no hotter now than back in the 60 s people ave gotten spoiled with air conditioning made hay in this heat every day all summer just stayed hydrated, suck it up butter cup