Yellowstone at a Crossroads: Science and Resilience in the Face of Climate Change
- Luis Diego Molina
- 4 days ago
- 4 min read
Welcome to the fourth installment of our blog series on how Ecology Project International engages students in understanding and tackling climate change at its program sites across the Americas. Catch up on the first post here, the second here, and the third here.
Yellowstone was the first national park ever created anywhere in the world, with a history spanning more than 150 years. And although it remains one of the least human-altered landscapes in the United States, the impacts of climate change are already becoming visible across this iconic conservation area.
The End of the Snow Kingdom
The park is known for its heavy winter snowfall. In a typical winter, accumulated snow on the ground can reach up to ten feet deep in the park’s lower elevations, and as much as twice that in higher areas, creating a landscape dominated by ice for much of the year.
The snowpack is essential for maintaining adequate water reserves throughout the year. As temperatures rise, water is gradually and steadily released into the environment. However, as global temperatures continue to increase, less snow falls each year and it melts earlier, reducing these vital reserves.
"The ecology of the place has evolved with large snowpacks that act as a reservoir of water released during the hot summer months. With climate change, reduced snowpacks and rain cause water to leave the system immediately through the rivers. Although some water soaks into the soil, it isn't held to the same degree as the snowpack", explains Joe Loviska, EPI Yellowstone Program Manager.
Today, there are 30 fewer days of snow-covered ground each year than there were five decades ago, and 60 more days with temperatures above freezing compared to the previous century.
The lack of environmental moisture creates greater vulnerability to wildfires during periods of extreme summer heat. Some burned forests may never recover, permanently transforming into grasslands and altering the landscape on a large scale.
Biological Mismatches and Stress on Wildlife
Rising temperatures over consecutive years reduce the protein content of grasses consumed by many herbivores, including bison, causing nutritional stress and forcing them to alter their migration routes.
Meanwhile, early “greening” caused by unusually warm springs can lead pronghorns to migrate after their forage has already lost much of its nutritional value.
Increasing heat has also allowed the mountain pine beetle to devastate whitebark pine forests. At the same time, wetlands in the region are predicted to decline by 40%, threatening the survival of amphibians such as the western toad.
As we can see, climate change is already having profound impacts on Yellowstone.
EPI’s Approach to This Complex Situation
Students participating in EPI courses engage in participatory science projects, collecting data and samples that contribute to a variety of ongoing studies within the national park.
The project most directly connected to climate change is the snow ecology study conducted during the winter months. Students dig snow pits up to nine feet deep, to measure the hardness, temperature, and density of the different snow layers that accumulate throughout the season. These measurements are linked to Snow Water Equivalent (SWE), which is crucial for understanding water reserves and how climate change is reducing Yellowstone’s snowpack.
In a good year, students can observe numerous snow layers within a single pit and complete all measurements. However, in recent winters, snowfall has declined dramatically, sometimes reaching only a single foot in depth, making it impossible to identify more than one layer.
When this happens, EPI uses a resource called “Impact Cards”, which contain scientific data about climate change impacts in the region, allowing students to teach their peers about historical temperature trends and climate-related disturbances.
As Joe explains, the lesson shifts in these situations: “Instead of teaching about snow science, we will talk about what’s happening here. Why isn’t there snow on the ground in January or February?”
During summer courses, students also participate in the “Home on the Range” study of bison and other ungulates. While the project focuses on animal behavior and collecting fecal samples, researchers also analyze how declining protein levels in grasses affect herbivores. Students additionally investigate how climate change adds stress to the ecosystem through droughts and wildfires.
Students also conduct amphibian surveys, since amphibians are considered bioindicators of habitat health. Because amphibians depend on wetlands for reproduction, monitoring their populations indirectly tracks the drying of wetlands caused by regional warming.
Holding On to Hope
Joe explains that beyond the scientific data, an important part of EPI instructors’ work in Yellowstone involves addressing the anxiety students experience as they come to understand these complex realities.
“Instructors have conversations with students about climate anxiety, and the weight that young people feel about all of this. These programs are really good places to have those conversations where we’re working with the real science, and we’re getting our hands on the land”, says Joe.
Although the environmental challenges posed by climate change are enormous, students in these courses learn that science is a crucial tool for resilience, and that they themselves can play an active role in that process.
“The science that we can do in the field keeps our knowledge high and keeps us aware of what’s happening, because if we are not aware, it will just roll right over us... we can do so many good, positive things to adapt and to change and to reduce the losses”, Joe concludes.
