As temperatures become hotter, droughts drag on, and wildfires grow more extreme, our bodies endure a rising toll. In fact, the World Health Organization calls climate change “the biggest health threat facing humanity.” What does that risk look like in Colorado? And how do we address it? We spoke to public health officials and climate experts from around the state to find out.

A Call To Action

The climate crisis is real—and it poses serious consequences for your health.

Pollution obscures the Denver skyline. Photo courtesy of 9News

In the mid-2000s, Dr. Jay Lemery became alarmed by the growing conflict between politicians and scientists over climate change. When he started looking into how doctors were reacting to the developing crisis, he was even more dismayed to discover that few health care professionals were wise to the health stressors of a warming world. So Lemery, now a wilderness and emergency medicine physician at the University of Colorado Anschutz Medical Campus, took up the cause himself. “My jam became to mobilize the clinical community,” he says, “both as advocates but also as practitioners of health.”

That’s how Lemery came to write (with his late mentor, Dr. Paul Auerbach) Enviromedics, one of the first books to explain how environmental changes will harm our overall wellness. The same year, Lemery created the Climate & Health Science Policy Fellowship at the CU Anschutz Medical Campus, a one-year intensive program that equips board-certified physicians to advocate for climate-change-informed health policy. This past fall, Lemery and the CU Anschutz Medical Campus doubled down by launching the Diploma in Climate Medicine, a 300-hour program for working health care practitioners who want a holistic understanding of the climate breakdown’s ramifications for human well-being.

The curriculum arrived on the heels of this past summer’s nearly global heat waves, which pushed mercury readings well above average across the globe—and in Colorado. According to a 2014 report from Western Water Assessment, the Centennial State’s average annual temperatures over the preceding three decades had increased by about two degrees and could balloon by up to five more by 2050, leading to a rise in heat-related illnesses and deaths.

Then there’s the Front Range’s notoriously poor air quality, an increase in the size and number of wildfires, and the impact that ecological change has on our mental health as we cope with new realities. “A lot of conversations in the climate policy space in Colorado over the last few years have been centered around, ‘We need data, we need data.’… And I think there’s been a shift recently to, ‘OK, we know this is happening,’ ” says Karam Ahmad, senior policy analyst at the Denver-based Colorado Health Institute. “We need to come up with short- and long-term solutions to protect people’s health and to come up with a sustainable way of living in Colorado.” On the following pages, you’ll find out how local doctors, health systems, and governments are attempting to do just that—and how you can use the information to protect yourself.

At-Risk Demographics

Climate change affects us all, but some factors put certain populations at greater risk.

Athletes: Training outdoors leaves athletes more exposed to air pollution and heat.
Children: Poor air quality damages developing lungs, and smaller body-surface area makes cooling down harder.
Chronically ill: Chronic respiratory and cardiovascular diseases can be triggered or exacerbated by environmental factors, such as air pollution and high heat.
Elderly: Reduced lung and heart function make coping with bad air, high heat, or stressful climate events more difficult.
Vulnerable populations: Outdoor workers and people experiencing homelessness—as well as people living near oil refineries, coal-fired power plants, or major highways (who tend to be people of color due to historical discrimination)—suffer increased exposure to pollution.

The State of Climate Change

Wildfires, droughts, and floods are nothing new in Colorado. But as the planet warms, some of these events are becoming more frequent—and potentially more extreme. “Climate change is essentially the climate on steroids,” says Becky Bolinger, assistant state climatologist at Colorado State University’s Colorado Climate Center. In other words: Disasters like the ones below, and their accompanying health impacts, become more likely as the climate warms.

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1. On July 20, 2019, the John Martin Reservoir near Lamar recorded Colorado’s highest known temperature, 115 degrees.

2. The three biggest wildfires in Colorado history all happened in 2020, after a spring and summer of exceptional drought.

  • a) Cameron Peak: 208,913 acres
  • b) East Troublesome: 193,812 acres
  • c) Pine Gulch: 139,007 acres

3. In 2018, the Upper Rio Grande River Basin’s snowpack melted off completely by May 16, the earliest date on record.

4. Amid an ongoing 20-year drought, the Colorado River Basin experienced its lowest recorded precipitation levels over a 12-month period from May 2020 to April 2021. As of March 2021, the basin’s water catchments—where water ends up after snow melts off—were only 74 percent of the median level from 1981 to 2010, according to the National Integrated Drought Information System.

5. Average temperatures in the Rio Grande River Basin are projected to increase four to 10 degrees by the end of the century. The rise will lead to faster evaporation from reservoirs, depleting water supplies that are already low due to drought and declining streamflow.

6. In September 2018, the Colorado Division of Water Resources placed water-use restrictions on the Yampa River for the first time due to low flow. Another restriction was put into effect on the Yampa in 2020.

7. Because of drought, in July 2021 the Ute Water Conservancy District near Grand Junction tapped water from the Colorado River for the first time in 65 years to supplement other sources and preserve its reservoir supply.

8. In 2022, the Ute Mountain Ute tribe, located in the Four Corners region, stopped cultivating 6,000 of the 7,600 agricultural acres it owns after receiving only 10 percent of the agricultural water it had rights to in 2021. The tribe had to lay off half its farmworkers.

Where There’s Fire, There’s Smoke

An environmental epidemiologist and data scientist at National Jewish Health, James Crooks researches connections between air quality and human health with a special focus on the Front Range, where pollution is notoriously bad—and even worse when wildfires spark.

5280 Health: The air along the Front Range isn’t great. 1 What pollutants are we inhaling on a daily basis?
James Crooks: Fossil fuel development 2 leaks gases like volatile organics 3, some of which are fairly benign, but some of which are dangerous 4. When we’re burning fossil fuels in our stoves or our cars, it’s producing nitrogen oxides, which are themselves bad and also make ozone worse. Volatile organics and nitrogen oxides combine in the atmosphere to make our ozone worse. Then there’s the whole wildfire thing.

James Crooks. Photo by Matt Nager

What’s in wildfire smoke?
All these things I’ve been talking about, plus particles. What’s in wildfire smoke depends so much on what the wildfire is burning through.
Right—and fires can dramatically increase the amount of tiny particles (aka particulate matter) in the air. Why are those microscopic particles such a huge health concern?
When most people think about the particles in the air, they’re normally thinking about something like dust in a sunbeam. That stuff can be bad for you, but the stuff that’s really bad for you is actually too small to see 5. The really tiny particles tend to be worse for you in part because they can get farther into your lungs, where you have a hard time coughing or sneezing them out. And we’re pretty sure some of them can pass through your lung lining into your bloodstream. We find evidence of particles in placentas, in the brains of people who’ve died and donated their bodies to science, in kidneys—and usually there’s some sort of immune reaction happening around that particle. Your immune system has to attack them. That immune reaction can raise overall inflammation in your body, which tends to contribute to the thickening of the arteries and things like that. When you’re constantly inflamed all the time, that’s a bad thing.

Who is most vulnerable to air pollution?
For people who have a chronic respiratory or cardiovascular disease, like asthma, or older people with heart disease, air pollution spikes increase their risks of having an acute event: a heart attack, a stroke, an asthma attack. But even low levels of air pollution over a long enough time seem to be bad 6. Statistically, we can show it’s decreasing people’s life expectancy. The impacts are a lot broader than people realize and a lot larger than people realize 7.


1. Colorado’s northern Front Range has been out of compliance with federal ozone standards since 2004. Some major contributors to our poor marks include metro area traffic, the oil and gas industry (especially operations in Weld County and the Suncor refinery in Commerce City), and Denver International Airport. But topography, wind patterns, and ample sunshine also play roles in trapping existing pollutants and transforming so-called precursor pollutants into ozone.

2. Like oil and gas wells and refineries.

3. Volatile organic compounds, or VOCs, are chemical compounds that easily turn into gas and interact with other chemicals to produce pollutants, such as ozone.

4. Benzene, a VOC present in tobacco smoke and vehicle exhaust (among other sources) can damage bone marrow, which can lead to anemia and can cause cancer.

5. Fine inhalable particles are 2.5 micrometers or smaller; according to the Environmental Protection Agency, the width of a human hair is about 30 times bigger than the largest of these particles.

6. A study published in Science Advances in 2020 used 16 years of Medicare data to find that decreasing long-term exposure to fine particulate matter could lower mortality risk by as much as seven percent.

7. Based on findings from Crooks’ 2019 study on the impacts of wildfire smoke on pregnancy outcomes, he estimates that a smoky year like 2020 (compared to a less smoky year, such as 2019) would increase the odds of preterm births (by three to 13 percent), gestational diabetes (six to 60 percent), and hypertension (16 to 74 percent).

Color Guard

Protect yourself from air pollution by following the rainbow.

Trying to spot the mountains through the haze is one way to gauge local air pollution. A better, more scientific method is to check the AirNow website or app. A partnership between the EPA, National Oceanic and Atmospheric Administration, and Centers for Disease Control and Prevention (among others), AirNow uses the U.S. Air Quality Index (AQI) to codify the safety of air quality at specific locations around the country, based on the presence of five pollutants: ground-level ozone, particle pollution, carbon monoxide, sulfur dioxide, and nitrogen dioxide. To safeguard your health, learn the system’s colorful cues.

Neighborhood Watch

Two Front Range projects look to raise awareness about the health effects of poor air quality.

Photo courtesy of Love My Air Denver

Love My Air Denver
Initially funded by a three-year grant from Bloomberg Philanthropies in 2018, this city program has partnered with 40 Denver Public Schools locations so far. Along the way, it’s advocated for air quality to be added as an asthma trigger to student health plans (so if pollution is worse than usual, kids with asthma might stay inside at recess), provided air-quality sensors for student experiments, and given students access to data sets they can use to create visualizations of Denver’s smog for class projects. The idea? Help students, families, and educators understand the impacts of poor air quality. Last year, Denver committed to funding the program once the Bloomberg grant runs out—which means that starting in 2023, Love My Air may expand beyond schools to recreation centers or community gathering places near you.

Boulder HEPA Filter Program
When pollutants fill the air outside, the best place to go is inside. But even your living room air can be riddled with toxins—especially during wildfire season. This past July, Boulder County Public Health (BCPH) installed air monitors and high-efficiency particulate air (HEPA) filtration units inside Canyon Point Apartments, a Boulder Housing Partners complex for low-income older adults. BCPH hopes to discover how outdoor pollution influences indoor pollution while also measuring how effectively HEPA filters clear the air. However, because this past summer saw fewer wildfires than expected, the pilot may need more than the initially planned six months to gather conclusive data. If the program proves effective, BCPH plans to expand to more Boulder County communities disproportionately affected by air pollution.

Too Hot to Handle

As summers grow hotter, Denver, Boulder, and Fort Collins are taking cues from cities and counties in other states to help residents escape the heat.

Athough hurricanes and tornados may grab headlines, heat is the number one weather-related killer in the United States, according to the National Weather Service, with a 30-year average of 138 deaths annually. Thanks to low humidity and cool nights, Colorado used to be less prone to the threat, but that’s changing: The Colorado Department of Public Health & Environment (CDPHE) recorded five heat-related deaths in the state in 2020, six in 2021, and seven through October 2022. Those numbers might not seem concerning—until you realize that they’re around twice the state average since 2002.

Even before that data was released, Denver, Boulder County, and Fort Collins had started preparing for the consequences of a warming Colorado by creating extreme heat plans. Triggered by advisories from the National Weather Service (NWS), these emergency protocols mobilize governmental resources to ensure that residents, especially at-risk populations, know boiling temperatures are on their way and to offer shelter from the scorching heat. Although common in warm-weather states like Arizona, this type of planning is new to Colorado, Katy McLaren, lead climate specialist for the city of Fort Collins, says: “We have a learning curve and gaps for how to best prepare, respond, and adapt to these conditions.”

Meanwhile, partially in response to reports of an increase in heat-related visits to Centennial State emergency rooms, the NWS has adopted a new model for declaring heat advisories. Instead of using Heat Index, a measurement developed in the 1970s that relies heavily on humidity to determine if heat is hazardous to health, in Colorado the NWS now uses HeatRisk, which factors in aspects like time of year and historical average temperatures. Enacted in 2022, the new metric resulted in four heat advisories in the Denver metro area from June to July this past summer.

Fortunately, Denver’s extreme heat plan also took effect last year. The response involved parks and recreation staff opening air-conditioned safe spaces in recreation centers across the city, while the Denver Department of Public Health & Environment (DDPHE) spread the word through various social media channels and informed people experiencing homelessness about the coming heat. “More people are probably familiar with [hypothermia]—like, what are the signs of it and how to avoid it,” says Emily Williams, director of communications for the DDPHE. “Now we’re trying to help educate people on what they need to do in the summer.”

Fort Collins and Boulder County have also taken lessons from places like Tempe, Arizona, which is working on an air-conditioned facility that will eventually be equipped with solar power and battery storage, and King County, Washington, which is testing heat pumps—contraptions that move hot air from one location to another—as an environmentally friendly cooling solution.

With the CDPHE and the Colorado Resiliency Office forming an extreme heat workgroup that first met in June 2022 to learn how the state can support local efforts, it’s only a matter of time before other Colorado cities and counties follow the leads of Denver, Fort Collins, and Boulder. “Extreme heat,” says former Boulder County Public Health climate change coordinator Grace Hood, “is very much going to be part of our public health and municipal planning vocabulary.”

No Sweat

Our state’s dry climate makes cooling off through perspiration easier, but Coloradans can still be affected by high temps. Here’s how to beat the heat.

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1. Stay inside air-conditioned buildings as much as possible. Air conditioning is the number one way to protect yourself against heat-related illness. If your home is not air-conditioned, you can visit one of Denver’s safe spaces if you feel the need to seek aid.

2. Drink more water than usual and don’t wait until you’re thirsty to imbibe.

3. Fans will not prevent heat-related illness in extreme heat. Take cool showers or baths.

4. Don’t use the stove or oven to cook—it will make you and your house hotter.

5. Don’t drink alcohol or beverages that contain caffeine.

6. Limit your outdoor activity, especially during the middle of the day when the sun is hottest.

7. If you experience any of the following symptoms, find shade, drink water, and consider calling 911: lightheadedness/dizziness; headaches; confusion; muscle cramps and aching; exhaustion/sluggishness; nausea, vomiting, or diarrhea; high body temperature, especially anything near or above 101 degrees Fahrenheit (100 degrees for kids); and feeling extremely hot but not sweating.

8. Consider visiting a cooling center at one of Denver’s recreation centers, including Athmar, Carla Madison, Cook Park, Green Valley Ranch, Highland, Eisenhower, Montclair, Hiawatha Davis, Platt Park, and Rude.

Open Minds

Climate change can damage our mental health too.

The climate crisis involves a lot of challenges beyond whether humankind will be able to, well, survive into the next century. According to Courtney Welton-Mitchell, assistant professor at the Colorado School of Public Health, changing climates are displacing people from generational homes, sparking grief or a loss of identity; wiping out livelihoods, especially in agricultural communities, which raises the risk for depression and other struggles; and driving extreme weather events associated with mental health outcomes like PTSD, depression, and anxiety. As awareness of the wellness impacts of climate change spreads, a growing number of organizations and individuals are stepping up to provide mental health support to Coloradans who need it.

Illustrations by Monica Hellström

Wildfire Survivors

How They’re Affected: After evacuating the family home only to return to ashes, wildfire survivors may experience a range of emotional reactions, from grief to anger to despondence and, in some cases, post-traumatic stress disorder.
Who’s Helping: Amanda Rebel, a licensed therapist in the Denver area who works one-on-one with adults who’ve experienced climate-related disasters or eco-anxiety, has seen so much need for care that this past fall she launched a climate-focused support group.

Teens & Young Adults

How They’re Affected: A 2021 study in Lancet Planetary Health found that 84 percent of 16- to 25-year-olds surveyed were at least “moderately worried” about climate change.
Who’s Helping: The Climate Psychology Alliance North America’s website includes a map that displays therapists in your area who can help young people process their emotions and find healthy ways to cope with climate change.

Science Educators

How They’re Affected: Science teachers have a crucial responsibility to teach the next generation about climate change without making students’ anxiety worse.
Who’s Helping: The education outreach arm of Boulder-based CIRES (Cooperative Institute for Research in Environmental Sciences) offers programs including HEART Force, a curriculum for rural teachers that engages students with hands-on environmental projects (because taking action is a key way to combat climate anxiety), and CLEAN, an online network offering resources and webinars on topics like how to manage climate-related stress.

Climate Researchers

How They’re Affected: For scientists in the field, climate change isn’t theoretical. But knowledge isn’t power when climate deniers hold office and refuse to pass legislation that would reduce emissions. Frustration? Meet sense of impending doom.
Who’s Helping: Good Grief Network, an international nonprofit, offers virtual small group meetings for peer-to-peer support. Groups meet for 10 weeks to build community ties and individual resilience to deal with climate grief or eco-anxiety.

Farmers & Ranchers

How They’re Affected: Unpredictable weather, unreliable water supplies, and increasing feed prices make it harder for farmers and ranchers to earn a living. Loss of livelihood and potentially their family’s land can lead to stress, depression, and substance abuse.
Who’s Helping: The Colorado Agricultural Addiction and Mental Health Program (from the Colorado Farm Bureau) provides vouchers for six no-cost telehealth counseling sessions to anyone living in rural Colorado. Participants choose from a list of approved counselors, and no diagnosis is required.