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The Rockies are warming twice as fast as the global average. The impacts are far-reaching

Travelling by bike means experiencing every distinct element of every landscape. You see the changing geography, hear different animals, and notice changes in the flora along the way. From the coastal rainforests in BC, the bizarre calls of the common loon, to the wide-open space and the smell of sagebrush in Montana and Wyoming, forests with miles and miles of dead trees (destroyed by wildfires and the mountain pine-beetle), to the snowy peaks in Colorado and the howls of the Coyotes that keep me up at night. When cycling along the Continental Divide, you do not miss out on any of them.

View on Logan Pass, Glacier National Park, Montana

What you do not necessarily notice that easily, however, is how much even the seemingly remote and intact landscapes such as the Crown of the Continent and the Greater Yellowstone Ecosystem are being impacted by climate change. To understand these impacts better, I took breaks from cycling to meet with different scientists and practitioners. Spread out over a distance of over 1300km, I met with Cathy Whitlock, Prof. of Earth Sciences at Montana State University, Member of the National Academy of Science and Lead Author of the 2017 Montana Climate Assessment; Clint Muhlfeld, Ph.D., Research Aquatic Ecologist for the US Geological Surveys Rocky Mountain Science Center in Glacier National Park; Ann Rodman, Director of GIS Operations at the Yellowstone Center for Resources, National Park Service; Dylan Hoffman, Director of Sustainability, Yellowstone National Park at Xanterra, as well as Trevor Bloom, Phenology Scientist and Community Ecologist at The Nature Conservancy in Jackson, Wyoming. Here is what they told me.

Rice Ridge Forest Fire in Lolo National Forest, Montana. 405km2 of forest got blazed during this megafire in September of 2017

Warming is happening quickly, very quickly

Since the 1950s, the climate in the Rocky Mountains has warmed by 2-3° Fahrenheit. The observed rate at which the climate is warming – here and elsewhere on the planet – is unprecedented in human history. “The last time the Earth experienced similar rates of warming (at the end of the last glacial period), it happened over thousands of years – now it is happening over decades,” Cathy Whitlock pointed out. “Ice core research indicates that the current level of greenhouse gases in the atmosphere is unprecedented over 800’000 years; and to see similar levels of atmospheric CO2 concentration – the driver behind present-day climate change - one would have to go back at least 3 million years in Earth history. The world at that time looked very different than it does today. It was much warmer, Greenland was free of ice, sea levels were tens of meters higher than today.”

"“We need to elect officials that see climate change as an important and number one issue.” Prof. Cathy Whitlock

Looking ahead, even under optimistic emission reduction scenarios, the warming trend will continue. The climate in this part of the US could well be 10°F warmer by the end of the century than it is today. “That would be a real deal-breaker and cause all of us to alter the way we live”, Cathy Whitlock said. For Ann Rodman, the climate scientist at Yellowstone National Park, the more she studies those trends, the more she has gone from being curious to being really concerned about the speed of change and what a big deal it is going to be. And she is not alone with her fear. “I found that the people who study climate are the people that are the most concerned. Everybody I know who studies it is getting more afraid of the future, and the magnitude of change,” she said.

From Many to Mini Glacier

At Glacier National Park, there is a place called “Many Glacier.” It is a popular hiking area. With a good dose of sarcasm, some jokingly call it “Mini Glacier.” Indeed, the glaciers of Glacier National Park rather look like patches of snow than the majestic glaciers like you might imagine it. At the end of the Little Ice Age, in 1850, Glacier National Park counted 150 glaciers. Today, only 25 remain. Their fate is uncontroversial: “The most conservative estimates suggest that all glaciers of the park will have disappeared by 2030” Clint Muhlfeld said. Maybe it is about time to think about a new name for the park.

“Restoring habitat and reduce invasive species is crucial for maintaining the resilience of native species to cope with climate change.” Clint Muhlfeld.

Together with melting glaciers, shrinking snowpack is among the most obvious and possibly most noticeable impacts of climate change in the Rocky Mountains. Today, there are 30 fewer days with snow on the ground in Yellowstone than in the 1970s (the numbers are similar throughout the Rockies). “We observe warmer winters, earlier snowmelt and more precipitation falling as rain during the shoulder seasons.” Clint said. “This leads to more early-spring flooding, but also lower and earlier run-offs, which in turns leads to lower flow in streams and warmer water temperatures in late summer,” Clint explained.

“So what?”, you may think. Biodiversity loss and destabilised ecosystems, a longer fire season and economic hits to the recreation industry are among the consequences of those geophysical changes.

From Gone Fishing to Done Fishing

Climate change often acts as a risk multiplier. It amplifies the effects of other trends that would have happened regardless of climate change. For example, the native bull trout and westslope cutthroat trout – both have inhabited local rivers for at least 14’000 years – have lost their fitness because of mixing with invasive species such as rainbow trout, translocated by humans to the Crown of the Continent. River habitat degradation and fragmentation reduce breeding options for the fish, weakening them further. Climate warming is accelerating hybridisation between introduced rainbow trout and native cutthroat trout, causing a dramatic decline in fitness of the native fish. “In this context, climate disturbance events, such as droughts and wildfires, can tip a species over a tipping point where there is no going back. Indeed, our findings underscore the potential for both irreversible ecological and evolutionary impacts on biodiversity, as a result of this combination of stressors," Clint said. Bull trout are listed as a threatened species under the Endangered Species Act, westlsope cutthroat trout are classified as a species of "special concern.

Clint’s research aims to educate managers across the trans-boundary Crown of the Continent Ecosystem on climate-informed conservation measures. The work that Clint and his team are leading is unique. For example, together with staff from Glacier National Park, the team has implemented a novel species translocation effort, moving bull trout to colder waters higher up in the mountain, as a means to help preserve this endangered native species. In times of climate change, species conservation and biodiversity protection has become more complex.

Sometimes, climate-informed conservation means shutting down rivers to recreational fishing as the stress from catch-and-release becomes too much for the fish that are already suffering from warmer waters or low stream-flow. One of the most notable examples relates to the iconic Yellowstone River. In 2016, an unusual climate-induced warming event facilitated the spread of a disease that killed thousands of fish. To protect the fishery, the river had to be shut down along a 183-mile stretch. “Such measures are always a direct hit to the local economy, even more so as they typically have to be taken during height of the fishing season”, Clint said. Indeed, recreational fishing is not only one of America’s favourite leisure activities, the blue-ribbon trout streams of Montana are visited by fishermen from around the world. “The consumer value of recreational spending in Montana is about US $7.1 billion year, with 71’000 jobs depending on it. When we have to shut down rivers, we are always shutting down a sector of the local economy.”

The Ripple Effects of Changing Phenology

A few weeks after my conversation with Clint, I met Trevor Bloom. We met in Blacktail Butte, inside Grand Teton National Park, where The Nature Conservancy is researching the impacts of climate change on phenology, a discipline that examines the seasonal timing of ecological events such as when bears emerge from hibernation or plants begin to flower.

"“Forming personal connection with nature is crucial to give us the inspiration to preserve the landscapes that we may lose.” Trevor Bloom.

Trevor told me that plants and flowers are now thriving three weeks earlier than in the 1970s. Warmer spring temperatures and a thinner snowpack that melts earlier each year are the big drivers behind it. Without climate change, flowering of plants would be in sync with the spring-emergence of pollinators or hibernating animals. Today, the mismatch in timing is having cascading effects. Bees might not find their nectar and bears might not find the roots they were used to find. The earlier flowering of plants also means earlier dry out, turning them into fuel for wildfire earlier than in the past, which contributes to a longer fire season in the West (which I will tell you more about in my next post, based on a conversation with Chris O’Brien, a wildfire firefighter from Boulder, Colorado).

Native Sagebrush landscape, Great Divide Basin, Wyoming

Dead Forests and Grizzlies on the Move

Cycling the Continental Divide means spending days in the forest. Some of those forests are beautiful and pristine. But it has been shocking to see all the high-elevation whitebark pines killed by the mountain pine beetle. The epidemic started about 10 years ago. Today, those forests look ominously desolate. Here is what happened: with warmer winters, the beetle proliferated, the pines were not prepared for it, and as the drier climate further weakened the pines, the balance was tipped in favour of the beetle.

“Climate change is a huge issue. If we don’t take action and change now, the consequences will be devastating.” Ann Rodman

In the first few years, the dead trees provide additional fuel to the increased risk of large forest fires. The die-off also means that an important food source for grizzlies is disappearing. Indeed, the grizzlies depend on the protein and fat-rich nut of the whitebark pine trees to get ready for hibernation. With many of the pines gone, the grizzlies’ behaviour is changing as they look for food elsewhere, including in lower-elevation forests and places occupied by humans. “Grizzlies are really good at finding food”, Ann Rodman told me. “So if they cannot find a food source they were used to find last year, they will move to a new area and look for new food sources. For us, this means that we will expect to see grizzlies where we usually would not have seen them. It creates a new reality for us,” Ann said. When grizzlies become a “problem”, some see the solution in their rifle, which is now the main cause of grizzly death in the Greater Yellowstone Ecosystem, when the bears walk out of protected areas. In my last post, I told you about how alternative ranching such as the approach developed by Malou Anderson-Ramirez’ allows for a more grizzly-friendly way of ranching.

Mountain Pine Beetle infested forest on Togwotee Pass, Wyoming

Increasing Visitation and Pressure on Natural Resources

Yes, there are some good news, too. For example, the growing season in Montana is now 12 days longer than it was in the 1950s. That is good news for some farmers. And new crops are growing in western Montana, such as the delicious cantaloupe melon, Cathy Whitlock mentioned. More tourists are visiting the mountains of cooler states in the lower 48, maybe in an attempt to escape the heat in the cities. The increased visitation, however, also means increased pressure on natural resources such as rivers and lakes, as well as the national parks of Montana and Wyoming.

“Something has to be done to address the increasing number of tourists visiting Yellowstone National Park.” Dylan Hoffman

For Dylan Hoffman, the Director of Sustainability at Yellowstone National Park, the number of visitors to the park is already a challenge, though. “You can say that the park is overly utilised with 4 million visits a year. We see more negative interaction with wildlife and more emissions from all the vehicles. This is a challenge for the park management, but also potentially puts in peril the National Park Service’s mission to conserve the resource not only for present, but also for future generations. “Nobody wants to say we have to introduce a cap, a lottery, or oblige people to make a reservation, but something has to be done to address the increasing number of tourists visiting Yellowstone National Park,” Dylan said. In the same breath he also points out that the park “has a huge opportunity to connect with all the visitors and educate them about climate change. There is an opportunity to talk to all the tourists about climate change in a science-based, non-politicised way. People love the national parks. It is a great platform for talking about climate change.”

Under the current administration, this opportunity will not be taken. Earlier this year, a climate scientist working for the National Parks Service lost her job because she refused to delete references to human-caused climate change in a report she authored. Her case made the news. Many others have resigned without making the news.

“Climate change is really such a pervasive problem”, Prof. Whitlock said towards the end of our talk. “It affects every aspect of our lives. I used to think that climate change was just a problem among a list of problems, but that is really not the case. We need to recognise that climate change is not a stand-alone issue, so that we can give it the attention it deserves. We need to elect officials that see climate change as an important and number one issue, we need to incorporate climate-smart technology into our infrastructure, make sure that vulnerable people are not left behind, and understand that addressing climate change creates huge opportunities for economic development and younger generations.”


On Monday 12th August, the White House has announced changes to the Endangered Species Act, signed by Richard Nixon in 1973. Critics say those changes will weaken the protection of threatened and endangered species and their habitats, and limit considerations of climate change as a threat to wildlife.



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