Why You Should Care That Colorado Is Cooking
The Centennial State has already seen a 2.5 degree bump in average daily high since 1980. By 2050, we’re set to see at least another 2.5 degree increase in annual average temps.
The notion that the planet is warming isn’t some crackpot theory put forth by polar-bear-loving environmentalists hell-bent on stymieing the fossil fuel industry. It’s a fact. Scientists of all political persuasions are sure of it, and they have statistics to prove it. Since 1880, the National Oceanic and Atmospheric Administration (NOAA), which is stationed in Boulder, has collected data on the planet’s average land and ocean temperatures. This past summer, the orb we call home reached an astonishing threshold: In 137 years of record-keeping, the mean temp on Earth had never been higher.
In Colorado, the trend is much the same. Since 1980, the average daily high temperature has jumped by two to 2.5 degrees Fahrenheit. “The warm years that we’re having now are all warmer than almost any other year we’ve ever measured,” says state climatologist Nolan Doesken. That temp increase is in large part the result of the amount of carbon dioxide we’ve pumped into the atmosphere, which serves as a kind of blanket around the world (see “Carbon Footprints” below). And unless we invent some magical CO2-sucking machine, Doesken expects Colorado to continue to warm. The question is: by how much?
Because climate prediction isn’t an exact science, there are dozens of models whose forecasts fluctuate based on assumptions about population, economic development, and energy use. One well-regarded—and somewhat conservative—prediction is that Colorado’s average annual temps will increase 2.5 to five degrees by 2050. Everyone from scientists at the National Climate Assessment, a federal agency that’s been studying climate change since 1990, to Denver’s city planners subscribe to this projection, with many believing Denver can expect at least a 3.5-degree bump. A few degrees might not sound like much, but consider what it takes to move the needle that far. A few degrees warmer on average means roughly 25 days at 95 degrees or hotter every year (versus the five or so we’ve had in recent decades). It means an average daily high near 90 degrees in the summer instead of about 85. And it means we drop from 150 nights a year below freezing to about 125. “This is about fires and droughts and farms and politics and urban growth,” says Scott Denning, a Colorado State University climate scientist. “It’s going to hit us where we live.”
The easiest way to get a sense for what a 3.5-degree upturn could mean for Denverites is to drive to southeastern Colorado, where cacti thrive and summer temps often tick past 90. Or think back to 2012, when the state experienced a very hot, dry summer. Those conditions led to a series of wildfires, including the Waldo Canyon Fire outside Colorado Springs, which burned 18,000 acres. During that summer, weather forecasters habitually pointed out that the conditions were unusual and extreme. But if we remain on the current upward temperature trajectory, Doesken says that by 2050 those “extreme” circumstances could represent the new normal.
With that scenario in mind, we reached out to climatologists, water experts, foresters, farmers, public health researchers, and city and state leaders to help us with some future-gazing. We wanted to know how a roughly 3.5-degree escalation could affect Denver. We also wanted to know what rising temps might mean for Colorado’s forests, water, recreation, agriculture, and residents’ health. The experts were eager to share their predictions and a few thoughts about how we can prepare for what’s coming, because at this point, there’s no stopping what we’ve set in motion—but we can prevent things from getting worse.
—Photo by Aaron Colussi
Charting everyone’s favorite greenhouse gas: CO2 levels over the past 800,000 years.
It’s not like the planet hasn’t seen temperature fluctuation before. But while Earth has experienced several ice ages and re-warmings since it was formed almost five billion years ago, the heating we’re seeing now can be linked directly to carbon dioxide from human activity. From the beginning of the last ice age—roughly 12,000 years ago—to the Industrial Revolution in the late 1700s, CO2 levels in the atmosphere were relatively stable. Then, around the middle of the 19th century, the line on the graph began to shoot up. Today scientists report there’s about twice as much CO2 in the atmosphere as there was for hundreds of thousands of years before the Industrial Revolution. And because the warming effects of increased CO2 in the atmosphere take years to become apparent, we’re just now feeling the impact of what we released in the 1990s. “We’ve cranked up the electric blanket,” says Jim Butler, director of NOAA’s global monitoring division. “Now we’re just waiting.”
Colorado’s Water: Why We Should Worry
A look at the fate of Colorado’s most important (and already stressed) resource.
Western Headwaters: Four major rivers originate in Colorado: the Arkansas, the Colorado, the South Platte, and the Rio Grande. Collectively, these rivers provide water to 19 states and Mexico. (In Colorado, where more than 70 percent of our water is west of the Continental Divide, a series of tunnels and ditches moves about 500,000 acre-feet every year from the Western Slope to the eastern side, where roughly 85 percent of Colorado’s residents live.) Researchers expect climate change to diminish some of these rivers’ flows—such as the Colorado River’s, which serves more than 30 million people—by as much as 20 percent by 2050.
Snow Stash: The snowpack that builds up in Colorado’s mountains helps feed Colorado’s four major rivers. In fact, snowpack accounts for between 70 and 80 percent of the state’s surface water—that’s water farmers use to irrigate and cities use for drinking water, yard-watering, fountains, etc. Over the past 50 years, peak snowpack levels have decreased, but it’s difficult to say by exactly how much. By 2050, researchers expect our snowpack to drop by 20 percent. According to Scott Denning, a Colorado State University climate scientist, part of that decrease will likely be attributed to warmer air during the winter, which will foment evaporation of the snowpack.
Earlier Melt: Historically, snowmelt in Colorado has begun in early to mid-April. By 2050, when temperatures begin cresting the freezing point earlier in the year, thus shortening our winters, the start of the runoff season could conceivably shift between one and four weeks earlier, which might mean encountering spring skiing conditions as early as February (see “Sayonara, Ski Season?” below).
Thirsty Crops: Earlier snowmelt translates into a longer drought season and lower stream flows later in the summer, neither of which is great news for agriculture, a $24 billion industry in the Centennial State. Farmers used to irrigating in August might not have the water they need under this 2050 scenario. And because it’s going to be hotter, those same crops will require more H20 than they do today. “How do you meet the growing demands of the city without harming agriculture?” asks Brad Udall, a water and climate researcher at the CSU-affiliated Colorado Water Institute. Fortunately, a lot of very smart people are trying to figure that out (see “Q+A With The President Of The Family Farm Alliance” below).
Go Fish? Aquatic life isn’t going to be jazzed about the lower stream flows either. “You’re going to have much warmer stream temps,” says Jeff Lukas, research integration specialist at the Western Water Assessment, part of the University of Colorado Boulder. “That’s a concern for cold-water fisheries. One of the impacts biologists are expecting is that trout will have to migrate upstream to find more tolerable temps.” And less habitat available for trout could potentially mean Colorado’s iconic fish will become threatened.
Liquid Assets: Of the 15 million acre-feet of water produced by Colorado’s four major rivers, the state keeps only about a third. The rest goes downstream to satisfy interstate water compacts. (For example, an agreement with Arizona allows Colorado to use up to 3.85 million acre-feet from the Colorado River Basin, as long as that doesn’t cause the flow at Lee Ferry, Arizona, to fall below a certain level.) In Colorado, about 85 percent of the water we use goes to agriculture; municipalities and industrial sectors drink up the rest.
Running Dry: Some impacts of earlier runoff, Lukas says, will be harder to anticipate. For instance, in Colorado’s centuries-old water rights system, users have specific dates of diversion (dates when they can take water out of rivers and streams), and if runoff shifts significantly earlier, those dates of diversion might become irrelevant—the water simply might not be there.
City Sips: Colorado is projecting a nearly 60 percent increase in population by 2050, most of it in cities along the Front Range. The increase means demand for water will grow by about the same amount, while supply could shrink by 20 percent. So where will we find the water we need? “My guess,” Denning says, “is it’s going to come from the farmers; cities are already buying irrigation water from farmers.” The transfer or selling of water rights from farms to cities—known as “buy and dry”—can devastate the communities once supported by agriculture, as has happened to a large degree in Crowley County. That’s in part why Colorado’s Water Plan is so important. The plan seeks to balance the growing demands of users (including the need for more infrastructure) with what is likely to be a lower supply of water—and it estimates about $20 billion will be necessary over the next 30 years to do it.
By the Numbers: 130 billion, the number of gallons of H20 Colorado’s Water Plan—a 480-page document released in 2015—suggests cities and the industrial sector should conserve each year to address a projected 500,000 acre-feet water shortfall by 2050.
—Courtesy of David Gilbert/Lawrence Berkeley National Laboratory
Change Agent: Lawrence Berkeley National Laboratory
What the Colorado River Basin tells us about climate change.
Studies looking at the implications of climate change typically look at very long-term scenarios—as in, decades from now. But the U.S. Department of Energy recently bestowed a multimillion-dollar federal grant to a team of researchers from the Lawrence Berkeley National Laboratory in California to study the Colorado River Basin in hopes of getting some shorter-term answers.
Ken Williams, the project’s chief field scientist (pictured), and his team are working on the East River in the Upper Colorado River Basin, near Crested Butte. They hope to learn how earlier snowmelt might affect plant life. “If snow melts early and plants start growing earlier, do they grow for a longer period of time, or do they die earlier?” Williams asks. It’s possible that as the time between spring runoff and the wet cycle of late-summer storms extends, drought-resistant plants such as sagebrush could become a more common sight on subalpine slopes and meadows. “Sagebrush can then have a set of impacts of its own,” Williams says. “It can intercept snowfall.” Less snowfall on the ground means less snowpack and, eventually, less water in streams. However, sagebrush also provides shade, which cools the ground, decreasing the rate of evaporation from the soil. So is the presence of sagebrush a net water loss or gain?
Williams and his team plan to have some data, and thus some answers, in the next three to six years. “I hope we’re able to provide forecasts for local and regional stakeholders,” Williams says. “It’s important for us to deliver actionable information concerning water availability and water quality.”
What You Can Do: WaterWise
WaterWise, a Denver nonprofit committed to helping cities use water more efficiently, has created its own water-saving checklists as part of the Live Like You Love It campaign. The lists present tips for how to conserve the amount and quality of the water we use. Like this one: Reducing your daily shower by as little as one or two minutes can save 700 gallons a year. —Sarah Soenke
Climate Change’s Impact On Agriculture
—Photo by Aaron Colussi
Q+A With The President Of The Family Farm Alliance
Pat O’Toole talks about the importance of water for farmers and ranchers in the West.
When Pat O’Toole spent a summer in the early 1970s on his future wife’s family ranch, the Colorado State University philosophy grad didn’t plan to stay. Both youngsters were law-school bound and wanted to study water law. Instead, they fell in love with the bucolic lifestyle, spent three years learning the ranching business, and ultimately took over her parents’ 135-year-old cattle, sheep, and hay operation northwest of Steamboat Springs. But O’Toole’s interest in water policy never waned. In 2005 he became president of the Family Farm Alliance, an irrigated agriculture advocacy group that has testified before Congress and published a 2007 report about water supply and climate change in the West. We talked with O’Toole about what’s happened since then—and what still needs to be done to secure the future of farming and ranching in Colorado. —Jessica LaRusso
5280: What’s the biggest challenge farmers and ranchers will face over the next three decades?
Pat O’Toole: The whole issue of warming in the West is going to pivot on water. We’re transferring our water away from food and ecosystems to [urban population] growth. But people didn’t move to Colorado to look at oil wells and cities. They moved to Colorado to look at ranches and meadows and mountains. That’s what we’re in the process of making choices about right now: Which Colorado do you want?
What effects of climate change are you already seeing?
In my world, we are seeing earlier runoffs. If the water’s running off earlier, you have to have storage to hold it so you can use it later for your irrigation, hay, fishery, and other habitat for animals. In many cases, you’re trying to do two things: You’re growing food, and you’re maintaining wildlife populations and biodiversity.
Is that why the Family Farm Alliance report suggests that conservation and more efficient technologies might not be the answers?
Research is coming out that in a variety of places—like the Western Slope where I live—flood irrigation is critical to migratory bird hatching, recharging of rivers, and producing hay for livestock. There’s this idea that efficiency is the answer to everything, and I call it the myth of efficiency. We’ve got to find what is the appropriate use of water in the appropriate landscapes.
What gives you hope for the future of agriculture in the West?
There are a lot of people coming together with diverse backgrounds and diverse agendas, and there’s a cooperative thing starting to happen in response to limited resources. It’s really neat to see partnerships forming and people working together. We live in a pretty resilient landscape, so we’re just going to try to figure out what nature gives us. Farmers and ranchers are in a poker game; you have to adapt to the cards you get.
What will your ranch look like in 2050?
My son Eámon is in charge of the cows and hay on the ranch. My daughter Meghan manages our sheep and recreation business [ranch stays, fishing, hunting trips]. We’re lucky to be in a really pretty place, so we think balancing both production and recreation will be part of our future.
What A Change In Weather Means For Our Crops
Agriculture has long dealt with weather variability—but the guessing game is getting harder.
First published in 1792, the Old Farmer’s Almanac was a sacred text among those who worked the land. Its planting charts, astronomical data, and weather forecasts gave farmers and ranchers a measure of confidence in a line of work with built-in uncertainty. Today, what is now called the Farmer’s Almanac is still published annually, but even the prognosticators at this 224-year-old all-things-ag institution can’t accurately foretell how climate change will affect how we raise crops and livestock. Why? Although farmers and ranchers deal with weather variability all the time, the guessing game is going to get more challenging in the next three decades because, as state climatologist Nolan Doesken puts it, “The route to 2050 will not be a smooth, gentle upward climb—it will be up and down.”
Fortunately, farmers are an adaptive bunch. To wit: A 2015 joint climate change vulnerability study by Colorado State University and the University of Colorado Boulder reported that alterations to seeding time and rate, fertilizer and pesticide application, and breeding of climate-tolerant varieties might help the ag industry incrementally adjust to the forecasted weather.
Still, spring runoff is projected to shift at least a week, if not a month, earlier by midcentury. This—coupled with increasing temps, particularly in the summer—may make farmers rethink their growing seasons and crops, says Reagan Waskom, director of the Colorado Water Institute, a research group affiliated with CSU. For instance, wheat is sensitive to high heat, and a longer frost-free season could stress the plants we use for flour production. More volatile weather—climatologists expect an increase in severe weather events, like droughts, but also more severe storms (because warmer air has the capacity to hold more moisture)—may pose a problem as well. Experienced farmers can often figure out how to coax some kind of crop to grow in almost any conditions. But, Waskom explains, if adverse weather threatens high-value crops like tomatoes and onions—things that require a lot of investment to grow and also have to look pretty to be sold at Safeway—farmers might swap them out for less risky crops such as alfalfa.
What worries Waskom the most, though, is water—and access to it. The warmer temperatures of 2050 could create what he calls a “double whammy” effect. Crops will need more water because of the heat, but more water will also evaporate as the mercury rises. These factors could lead to lower yields in some crops, including corn. It’s not that farmers won’t be able to raise or grow something. But whatever it is, farmers are going to need water to do it—probably more than they need now. As supply goes down and demand goes up, Waskom envisions a worst-case scenario that could result in a potentially ugly fight between city demand and rural supply. “Agriculture,” he says, “is what always seems to lose out.”
By the Numbers: $409 million—the estimated loss statewide in 2012 due to drought-related stress on crops.
What You Can Do: Farmers’ Markets
Shop at farmers’ markets. Not only are you directly supporting Colorado growers, but you’re also reducing the greenhouse gas emissions that come with transporting food from, say, California to Colorado. —SS
Recreation And Rising Temperatures
Photo courtesy of Sasha Juliard
Sayonara, Ski Season?
What warmer weather will mean for the Centennial State’s unofficial winter sport.
Don’t panic, powderhounds—at least not yet. There will be less snow in 2050, but Colorado is better off than most other American ski regions. “That’s because most of our ski resorts are at such high elevations,” says Melissa Bukovsky, a project scientist who studies climate change at Boulder’s University Corporation for Atmospheric Research (UCAR).
Many popular Colorado ski resorts’ bases sit at or above 9,000 feet, where, in 2050, snowpack levels are expected to be 80 to 90 percent of what’s considered normal. Not great, but still very skiable—providing, of course, that winter temps still regularly dip below freezing (as they’re supposed to) so that resorts can supplement the loss with snow-making machines. (If you think back to the 2012-’13 ski season, you’ll have an idea what 80 percent of “normal” snowpack feels like.) The real trouble starts below 8,000 feet: There, snowpack is likely to be, at best, 70 percent of modern levels. At 6,000 feet, would-be skiers could encounter as little as 40 percent, Bukovsky says. No wonder Aspen Snowmass—where bases range from 7,870 (Buttermilk) to 8,040 feet (Aspen Highlands)—has been such a leader in the fight against climate change. Although much of Aspen Snowmass’ terrain soars above 12,000 feet—meaning most of it will likely still be skiable in 2050—area residents are mobilizing. In 2015, the town of Aspen met its goal of generating all of its electricity through renewable resources: 99 percent of Aspen’s power comes from wind and hydroelectricity, and one percent comes from landfill gas.
While the loss of snow might not be overly concerning (yet—things look bleak for 2100), the quality of snow you’re riding could decline. Bukovsky points out that the spring freeze-thaw cycle that creates icy runs in the morning and slushy ones by afternoon is likely to become more common. And your ski season is probably going to get shorter: Scientists expect the spring melt, which typically starts in April now, to shift up by as much as a month. We’re betting your ski pass won’t be getting any cheaper, though—after all, the resorts are going to need that money for more snow-making machines.
All About That Base
Colorado’s five lowest-elevation ski resorts.
Resort: Howelsen Hill Ski Area
Base (in feet): 6,696
Resort: Steamboat Resort
Base (in feet): 6,900
Resort: Beaver Creek Resort
Base (in feet): 7,400
Resort: Buttermilk Ski Area
Base (in feet): 7,870
Resort: Sunlight Resort and Ski Area
Base (in feet): 7,885
By the Numbers: $4.8 billion—the annual economic impact of Colorado’s ski industry.
—Photo courtesy of Protect Our Winters
Change Agent: Protect Our Winters
The snowsports industry is sending out an SOS: Save Our Season.
Chaired by Aspen Snowmass’ vice president of sustainability, Auden Schendler, Protect Our Winters is one of the foremost climate advocacy groups for the winter sports industry. The alliance was founded almost a decade ago by pro snowboarder Jeremy Jones after he noticed many of the resorts he loved riding were closing early because they didn’t have enough snow. Today, the nonprofit knits together athletes, resort owners, and snowsports industry professionals from all over the world to raise awareness about climate change. Recent efforts have included a letter-writing campaign that asks the new Trump administration to make action on climate change one of its top priorities in its first 100 days. Thousands of letters will be hand-delivered to the capital right after the inauguration in January. There’s also Hot Planet/Cool Athletes, a school assembly program that to date has helped educate more than 45,000 young people about the scourge of climate change.
The Centennial State’s Flow Woes
The ripple effect of earlier melt on our water fun.
Colorado’s Class IVs and Vs aren’t going anywhere just because there’s earlier snowmelt: The paddling season will simply start sooner. River rats might have to pack their runs into a shortened early season—and potentially deal with more obstacles later in the summer as flows remain low for longer. No big deal, right? It is if you’re trying to make a living from the activity, as communities like Buena Vista and Salida are. The problem with earlier snowmelt and drought is that it pushes the rafting season into months—like April—that aren’t typical tourist months (kids are still in school). That might lead to a loss in business for many river outfits and the communities they help support. Look no further than 2012 for a prime example of what a drought year can do: That year, the Colorado rafting industry saw a 17 percent dip in visitation.
Boaters, too, might experience some hiccups since a reduction in snowpack eventually translates to lower water levels in popular reservoirs like Horsetooth and, farther downstream, Lake Mead and Lake Powell. (In May, Lake Mead hit its lowest level ever.) That means more exposed rocks, warmer water, and a potentially higher concentration of illness-causing bacteria. Not exactly an enticement to strap on water skis.
Fly-fishermen also may have to adjust their practices—and locations. Colorado’s coveted trout prefer clearer, colder waters; as low flows lead to warmer water temps, the fish might migrate upstream or dive down deeper to stay cool. All that dry-fly action fly-fishermen love might vanish. Easy access to fishing permits could disappear, too: If the higher temps lead to a reduction in trout habitat sizable enough to have a negative impact on the population, wildlife officials could impose harsher restrictions.
Wait, Our Mountains Are Changing Too?
Currently, sea level is rising roughly 0.13 inches per year. If you’re wondering what that has to do with Colorado, consider this: Elevations are based on current sea level. If the oceans get higher, our mountains get shorter. The present rate of rising seas isn’t fast enough to knock even our shortest fourteener (Sunshine Peak, 14,001 feet) off the list by 2050, but it’ll be getting close. × The views from the tops of those mountains aren’t as good as they used to be either. Pollution has obscured how far you can see from peaks in Rocky Mountain National Park by 46 miles, according to the EPA. In Great Sand Dunes National Park and Preserve, it’s even worse: In natural conditions, you could see 55 miles farther than you can now.
What You Can Do
Reduce your carbon ski-boot-print by carpooling to the mountains. The nonprofit skicarpool.org connects Colorado resortgoers with other skiers and riders heading up I-70. —SS
Climate Change and City Life
A 2050 Day In the Life Of A Denverite
Bad news, city dwellers: Colorado’s increasing temperatures are going to be felt most acutely in Denver. That’s because of something known as the heat-island effect—that is, urban centers’ tendencies to be hotter than rural areas, thanks to the surface properties of buildings and streets and decreased vegetation. In fact, Denver has the third worst heat-island effect in the country, behind Phoenix and Salt Lake City. With that in mind, we consulted with city officials to see what the everyday implications could be for Mile High City residents in 2050. (If we can still call it that: With rising sea levels, our mile-high moniker might also be at risk.)
9 a.m.: Your morning light-rail ride to work, you’re reminded that you’ll need to leave the office a little early today because your commute home will take longer. When temps crest 95 degrees, the light rail has to slow down to avoid damaging the rails and creating “sun kinks”—essentially a bending or buckling of the rails that can occur when they get too hot. In the late 20th century, Denver only saw around five days above 95 a year; in 2050, we’ll see about 25. (Related: The 2016 summer delays on the brand-new A Line to the airport were caused in part by overhead rail lines sagging as a result of the heat.)
10 a.m.: A contractor calls you with an estimate for re-flooring your basement, which flooded in last week’s massive thunderstorm. You decide to wait a couple of months because you know more severe storms are likely to come. Storms that drop more than a half-inch of precipitation in one day—like that one on Denver’s Bike To Work Day in June 2015—are expected to increase by about 15 percent by 2050.
Noon: At lunch, your wife texts to tell you she’s not going to make it home from her business trip in Phoenix tonight. Her flight was cancelled on account of stifling temperatures: Some planes can’t take off when the thermometer creeps beyond 115. With more and more days ticking past 100 degrees in Denver—at least three a year are estimated for 2050 (compared to less than one on average in recent decades)—you wonder when that will start to become an issue for Denver International Airport, too.
4 p.m.: You log in to Xcel Energy’s intelligent grid program to find out how much you can expect to pay to power your AC when you get home. Launched in 2017, the program allows customers to track energy usage and prices on a real-time basis. And since the hours between 4 and 6 p.m. tend to be peak-use hours midweek in the summer, you want to know what you’re going to pay to cool off. You at least feel better about where your power is coming from: Demand on the power grid has increased by at least 10 percent since 2016, but Xcel has kept up. Plus, it’s expanded the portion of its power that comes from renewable sources to more than 35 percent.
6 p.m.: You nix your post-work run around Washington Park. It’s still too hot, and with fewer trees, there isn’t as much shade to keep you cool. Denver lost a significant portion of its ash trees—which once accounted for about 15 percent of the urban canopy—to the emerald ash borer in the early part of the 21st century. Drought and damage from increasingly severe weather took out many more, especially thirsty varietals like cottonwoods.
By the Numbers: $2 million—the amount the city of Boulder has netted annually since 2007, when it became the first city in the nation to establish a tariff—the Climate Action Plan tax—specifically for sustainability. All of the money goes to fund efforts that reduce greenhouse gas emissions.
How The City Hopes To Avoid The Apocalypse
Programs and initiatives that help mitigate and adapt to our changing world.
If the doomsday predictions have you freaked out, you’re not alone. They’ve got city leaders nervous, too: In 2007, Denver unveiled its first Climate Action Plan and then updated it two years ago, calling for an 80 percent reduction of greenhouse gas (GHG) emissions by 2050. Then, in 2014, the city released the Climate Adaptation Plan. Together, these plans outline the likely scenarios and present ways to reduce our impact and adjust to our new world. Very few of the suggestions come cheap.
Say Goodbye To GHGs. The largest portion—35 percent—of Denver’s GHG emissions come from commercial energy use. If we’re going to reduce our GHGs by 80 percent, we’ve got to start there. That can be as simple as tracking your building’s energy usage: Benchmarking alone has been shown to reduce energy use by up to three percent. And it’s free. Retrofitting buildings with more efficient heating, cooling, and lighting systems is not. But organizations that do upgrade often see returns on their investments within a few years. The city, for example, has already reduced its energy usage by 23 percent since 2011 because of such retrofits.
Replace Our Trees. Many of our trees are water-guzzlers and could be in trouble in a drier climate. We should care for reasons beyond aesthetics: Trees eat CO2. Plus, in Denver the shade from trees helps mitigate the heat-island effect. In 2016, city foresters spent close to $1 million to combat the emerald ash borer and to plant trees that can withstand a harsher climate. That can be challenging given the predicted increase in severe weather. “We’re having to plant trees that can handle diverse snow and wind loads—which is odd because things that can take those higher temps aren’t typically evolved for climates with snow,” says Office of the City Forester’s Sara Davis.
Maintain The Lanes. The lifetime of a road is predicated on the temperatures to which it’s exposed. If an agitated Mother Nature seriously jacks up the mercury, city and state leaders could be looking at having to repair or service Colorado’s roads much more often. If officials want to mitigate the warming effect of asphalt (which absorbs heat in a big way) by using concrete (which reflects heat and lasts longer), they’ll need to be prepared to bust out the checkbook. Asphalt costs between $5 and $15 a square yard, while concrete ranges from $100 to $300 per square yard—a 2,000 percent difference.
What You Can Do: Denver Energy Challenge
The second-largest contributor (16 percent) to Denver’s GHG emissions is residential energy use. That’s you (and us). Get some free insight into how to reduce your power consumption with a gratis energy efficiency assessment through the city’s Denver Energy Challenge program. The city has contracted with energy advisers to provide in-home assessments as well as guidance about tax credits, rebates on energy-efficient appliances, and more. Since the program launched in 2011, more than 10,000 Denverites have taken part—and they’re saving an average of 23 percent on their energy bills.
—Courtesy of Scott Skogerboe
Change Agent: Scott Skogerboe
There’s nothing like adversity to reveal what you’re made of—especially if you’re a tree.
That’s the principle behind the work of Scott Skogerboe, head plant propagator at the Fort Collins Wholesale Nursery. For more than 20 years, Skogerboe’s been breeding the tough, adaptable plants—Russian hawthorns, burr oaks—that foresters in Colorado cities are now using to prepare their parks and urban streets for the hotter, drier, and more extreme weather expected in the coming decades.
Skogerboe’s quest to create the climate-ready plants of the future began with a college field trip. In 1992, he visited an abandoned federal research station in Cheyenne, Wyoming, where trees and shrubs had been imported from around the world and tested for their adaptabilities to the harsh environment of the high plains. When he first visited the station, more than 70 percent of the plants had already succumbed to neglect. The survivors had weathered the howling wind, piercing sun, and blowing snow of the prairie without irrigation or care for nearly 20 years.
Skogerboe began making pilgrimages to take cuttings from those hardy prairie plants. “We may have learned more [about growing adaptable plants] since the Cheyenne station closed than we did while it was open,” Skogerboe says. Today, he raises the survivors’ progeny and sells them to cities around the Southwest, from Denver to Salt Lake City to Albuquerque. In the coming years, Skogerboe hopes his resilient plants will help ensure your weekend walks through City Park still come with some shade. —Nelson Harvey
Hot And Bothered: Climate Change And Human Health
So concerning are the potential effects of climate change on human health that this past spring, researchers throughout the Front Range formed the Colorado Consortium on Climate Change and Health. Here are a few of the issues they’re studying.
Gesundheit! Not only does a warmer climate mean a longer growing season for many of the plants that already irritate human allergies (ragweed, for example), but the hotter temps—coupled with more CO2—also trigger plants to produce more pollen. Result: Kleenex and Claritin stock prices soar.
Breathless: In 2016, Denver ranked as the eighth most polluted city in the country in terms of ozone, according to the American Lung Association. As global warming increasingly bakes the Mile High City, breathing easy is only going to get more difficult for Denver residents with asthma, a condition exacerbated by high ozone levels. Ozone production can increase with hotter, sunnier weather thanks to a noxious stew of oxides of nitrogen, volatile organic compounds (VOCs), and light. As an added bonus, the increase in wildfires (see “Three Ways Climate Change Will Impact Colorado’s Forests’ below) will up the amount of particulate matter in the air—another irritant for those suffering from respiratory ailments.
Taking Heat: The reality is that whether you’ve got asthma, allergies, a heart condition, or distressed kidneys, hot weather will exacerbate things. “Heat waves are a force multiplier,” says Rosemary Rochford, director of the Colorado Consortium on Climate Change and Health.
Exposed To The Elements: Whether you work outside or—like half of Denver homes—don’t have AC, the stress of high temps can lead to everything from dehydration to decreased kidney function to death (particularly for our elderly population). And climatologists expect there will be more extreme heat events in the future. It’s tempting to think warmer winters might reduce weather-related deaths (especially among Denver’s homeless), but the CDC predicts the loss of life due to increased heat will outweigh any such small gains. To that end, the city has begun developing an Extreme Heat Plan that will likely rely in some ways on the framework in its Cold Weather Plan to ensure Denver’s citizens have safe places to go.
Swim With Caution: E. coli.—and plenty of other bacteria that can cause GI discomfort, severe illness, and even death in some cases—are among the creatures that love (and reproduce more) when it’s balmier. Humans can contract these things by swimming in, or swallowing, waters (hello South Platte River!) that contain them. The city of Denver has already acknowledged that this is an area of concern; the Department of Environmental Health and the Office of Economic Development are working to create a surveillance system for waterborne diseases that can help predict—and thus prevent—potential epidemics.
Break Out The DEET: Colorado mosquitoes are doing a happy dance at the thought of warmer temperatures, which allow them to live longer and breed more rampantly. Expect to see increased incidences of West Nile virus and potentially scarier illnesses such as dengue fever, especially in areas that contain large pools of stagnant water, like open flood drainage canals or irrigation ponds.
Why We Should Fear For Our Forests
—ACES CEO Chris Lane at Hallam Lake, near Aspen; Photo by Aubree Dallas
The Forests Of Our Future
The Aspen Center for Environmental Studies has developed a crystal ball (of sorts) for Colorado’s woodlands.
The folks at the Aspen Center for Environmental Studies (ACES), a nonprofit environmental science education organization, are into forests. Like, really into forests. They’ve been studying the trees of the Roaring Fork watershed for more than five years in an attempt to understand what’s already shifted and what’s likely to develop as a result of climate change. Armed with their findings, which the institution compiles in annual State of the Forest reports, their mission is to present that information—to students, policymakers, the public—in a way that’s not only accessible and interesting but also actionable for those who live in the West. ACES’ number one objective is encouraging people to do something. And for good reason: By 2100, the western half of the United States could lose up to 40 percent of its forests as a result of global warming—if residents don’t take the initiative to stop it.
In late 2015, ACES released a high-tech web-based tool called Forest Forecasts. The user-friendly interface lets visitors to the website look at the best- and worst-case climate change scenarios for forests—specifically, 100 species of trees—in Colorado and the West. The model is incredibly detailed, allowing a user to zoom in on Trail Ridge Road in Rocky Mountain National Park, the Flatirons in Boulder, or her favorite trail off Boreas Pass near Breckenridge. The visual results are striking: For many tree varieties, the habitat suitability shrinks dramatically as the user plays with the all-too-possible variables. ACES’ goal for Forest Forecasts was lofty. “Our biggest hope was that the tool would be used by decision makers,” says Chris Lane, CEO of ACES. “A little over a year later, decision makers—like local governments and the Forest Service—are noticing it and realizing its potential and usefulness for creating resilient forests.”
It’s Not Just About The Trees
The decimation of our forests should be a tragedy of its own accord. However, too many of us ignore the Loraxes of our time unless they can demonstrate why we Once-lers should care. Here are a few reasons why.
1. More than 60 percent of all new houses in the West are built on the urban-wildland interface, where nature meets development. When the inevitable forest fires ignite and spread, the trees might not be the only things burning.
2. Trees are sponges for mercury, lead, and other metals in the ground; when they burn down, more of those heavy metals penetrate the soil and could eventually wash downstream to water treatment plants that might not be equipped to handle the increase. If you don’t know what high levels of lead contamination in drinking water lead to, you should ask a resident of Flint, Michigan.
3. As forests decline, experts like ACES’ Chris Lane say snowpack will melt faster and water will run off more quickly. Areas affected by recent wildfires can allow large amounts of water to build up and pulse downstream—an ecologically dangerous situation. Flooding near the site of the 2002 Hayman Fire, one of the largest wildfires in state history, for example, has had ruinous effects on communities, public infrastructure, and area water supplies.
Photo by Sarah Boyum
Three Ways Climate Change Will Impact Colorado’s Forests
Catastrophic Fires: As a result of more severe drought conditions, experts expect more wildfires to burn across Colorado and the West. In fact, in 2015 more than 10 million acres burned in Colorado—an all-time high. And a number of factors are making what’s already a bad situation worse. When the U.S. Forest Service’s budget gets eaten up by fire suppression (as 52 percent of the budget did in 2015), less money is available to spend on preventive fuel mitigation and habitat restoration. And thus a vicious cycle is born.
Uphill Tree Migration: A 2.5- to five-degree change in temperature is worth about 1,000 to 1,500 feet in elevation gain, meaning living things that prefer cooler air may have to trudge uphill to find it. “Trees don’t just get up and walk like in The Lord of the Rings,” says Scott Denning, a Colorado State University climate scientist. Instead, trees at lower elevations will die and new saplings will slowly migrate toward chillier climes. One recent study noted that some species of trees in the high Sierra Nevadas are moving up the hill at .000000135 mph, or about 500 vertical feet every 80 years.
The Replacements: When the habitat suitability for a specific tree species declines because of climate change, that tree might simply disappear. “In places where there were once aspens, spruces, and lodgepole pines,” says ACES’ Chris Lane, “there will likely be junipers, gamble oaks, and piñon.”
Where The Wild Things Aren’t
What you might be more (and less) likely to see when you go hiking in 2050.
More Raccoons: Dubbed “habitat generalists” by wildlife biologists because of their ability to live in a range of temperatures and conditions, raccoons—like deer, elk, and coyote—will likely do just fine with rising temperatures. And so will the ticks, mosquitoes, and other blood-sucking creatures that come along with them.
More Beetles: Hope you like beetle-kill furniture, because there’s likely to be plenty of it by 2050. Milder winter temperatures allow bark beetles, which damage trees themselves and can also carry tree-killing fungi, to proliferate—and mow through trees already stressed by drought. (Drought weakens trees, making it difficult to fight off infestations.)
More Wildflowers: You likely won’t see more wildflowers; you just might have more chances to see them thanks to a longer season. One recent study found that Colorado’s bloom season had moved from late May through early September to late April through late September. That doesn’t sound so bad—but researchers don’t yet know the effect it could have on pollinators like bees and butterflies.
Fewer Aspens: Our iconic leaf-peeping star will likely become a rarer sight. Aspens are thirsty plants that require a good deal of H20 to flourish. Their root systems are fairly shallow, which means they’re at risk in drought years (the new norm in 2050) because as the hotter temps evaporate moisture from the ground, they can’t tap deeper stores of water. Result: a potential aspen die-off, even worse than during the 2002 drought.
Fewer Fir and Spruce: As we see more wildfires, we might see different kinds of forest regrow—ones perhaps without as much Engelmann spruce and subalpine fir. A recent study co-written by University of Colorado Boulder researcher Brian Harvey revealed that these species do not recolonize burn areas as well as, say, lodgepole pine. The result may be sparse, less diverse forests growing on these burn sites for decades.
Fewer Pikas: Adapted for the brutal winter conditions of high elevation, pikas don’t fare well in balmier climes. The tundra zone’s cutest critter can’t cool itself off and has been known to die from just a few hours’ exposure to temperatures higher than about 80 degrees. While other animals might simply move farther up the mountain to adapt, pikas are already at the top and have nowhere to go—except, potentially, extinct.
What You Can Do: Colorado State Forest Service Funds
Give your money or your time to one of the Colorado State Forest Service’s projects. Five tree-related funds put your spare change to use through planting, managing, or protecting the state’s forests. The Restoring Colorado’s Forests Fund, which helps plant seedlings on landscapes stripped by wildfires and other disasters, is the most popular fund. —SS
By the Numbers: 11—Approximate degrees by which Denver is estimated to warm by 2100 if the rate at which our planet is heating up continues (i.e., barring large-scale cutbacks in CO2 emissions). At that point, Denver won’t feel like Pueblo or even Albuquerque. Another 11 degrees or so and our average summer high will be closer to 97—the average high in Pharr, Texas, which is about 16 miles from the Mexico border.