JACKSON, Wyo. — An interactive climate presentation at the Teton County Library on Monday, Sept. 16 predicted that climate in Jackson Hole and in the Greater Yellowstone Ecosystem will change more rapidly in the 21st century, compared to the last few decades.
Dr. Bryan Shuman, Professor of Paleohydrology, Paleoclimatology and Paleoecology at the University of Wyoming and co-leader of the 2021 Greater Yellowstone Climate Assessment, shared climate simulations to help people understand what changes are to come in the near future as temperatures continue to rise. He said that the University of Wyoming project, Wyoming Anticipating the Climate-Water Transition (WyACT), was developed to prepare for climate transition and assist communities in adapting to the future changes.
“We often talk about how climate change will impact the next century, but we rarely talk about immediate impacts,” Shuman told the audience. “My goal as a college professor is to try to supply the most accurate information so we know how to adapt and change in the future.”
Shuman asked audience members to share what they think are the most pressing climate change concerns. Participants used an app to submit these words, which then appeared on the Ordway Auditorium multimedia screen: wildlife, drought, water, snow, trees, temperature, wind, landslides, recreation, trout, rivers, wildfire and more.
Shuman explained the basic science behind the earth’s changing climate. He said that the primary greenhouse gas, CO2, traps the heat radiating from the earth’s surface, preventing it from escaping into space.
“Every time CO2 rises up, it’s like putting another layer of insulation into the atmosphere,” Shuman said.
He explained that scientists have been able to record CO2 levels over the past million years by measuring the bubbles in ice layers. Each ice layer indicates the level of C02 during that period of time.
“During the last ice age, when glaciers covered the mountains, it was five to seven degrees colder and CO2 was measured at 180 parts per million (ppm) resulting in a weak greenhouse effect,” Shuman said. “The ice age ended about 15,000 years ago when CO2 levels began to rise. Today, CO2 is at 422 ppm, which is a level never before experienced by humans.”
According to Shuman, the planet is on track to skip the next natural ice age cycle entirely due to increased warming. Shuman said that the amount of CO2 in the atmosphere has grown exponentially every year. The yearly increase in CO2 is calculated by measuring the growth of population and multiplying that by the growth of energy consumption per person. Shuman says that one of the reasons CO2 continues to accelerate exponentially is due to an increase in demand for AI tools, which can take up as much energy as a small city.
On a local level, weather stations in Jackson, Moran, Driggs, Alta, Dubois and Pinedale have recorded strings of above average temps over the past decade. Warming evening temperatures have caused snow to melt faster and the loss of frost at night is expected to extend the fire season, according to the Greater Yellowstone Climate Assessment. Shuman went on to say that it is likely to become 2.7 degrees (F) hotter between now and 2043. Once CO2 reaches 500 ppm, Jackson Hole will see more precipitation, but this means less snow and shorter winters.
“Jackson is famous for its snow pack,” Shuman said. “It’s essentially water supply to farmers in Idaho and the snow drives the winter economy. There will be a slight increase in winter precipitation, but the amount of snow accumulation will decline as snow switches to rain with warming. Jackson will start getting more rain on snow events, which will melt the snow.”
Lower elevations, including the valley floor and regions where people nordic ski, will experience the greatest snow loss. At the same time, there are expected to be longer periods of dry days without precipitation during the summer. While the shoulder seasons, fall and spring, will have increased precipitation. Shuman did say that Jackson has been slower to change than a lot of the northwest. Salt Lake City’s average temperature increases have been twice as large as increases seen in Jackson.
Shuman stressed the importance of mitigating carbon emissions to allow for communities to have an additional 40 years to plan before the arrival of what he calls “the opposite of the last ice age.”
“The biggest uncertainty is how much more carbon we can put into the atmosphere,” Shuman said. “If we don’t do any mitigation from this point on we will double this heat and end up at 1000 ppm. We have to take action now to prepare for the outcome.”
