Diana Six, Loren Acton, Eric Grimsrud, Steven Running, Bruce Smith and Kyle Strode

As scientists who have lived and worked in Montana, we understand the scientific principles demonstrating that human activity is rapidly changing our climate. That is why we joined more than 100 other scientists across Montana in sending a letter to our top elected officials calling on them to support policies that reduce carbon pollution.

Thousands of scientists have produced thousands of studies on the causes and impacts of climate change. Each of those studies has undergone a rigorous peer review process. Building such an extensive body of evidence is a careful, slow and painstaking process, which rarely yields broad agreement. That’s why it is remarkable that 97 percent of scientists who study climate change say that it is real, and largely caused by human activities that produce carbon pollution.

Climate change is a major concern for Montana. Scientists have documented that spring snowpack is melting on average two weeks earlier than in the 1950s. There has been a two-month extension in the wildfire season since the 1980s. August stream flows now average 20 percent lower than in the 1950s. These impacts are already affecting agriculture, recreation, wildlife and water resources.

The effects of climate change go beyond water and fire. The recent outbreak of the tree-killing mountain pine beetle is more than 10 times larger than any previously recorded, and includes the beetle attacking two new tree species and thousands of square miles of forests in high elevations.

Given the impacts we’re already experiencing after 1.5 degrees Fahrenheit of warming, imagine our children’s future. Scientists predict temperatures will increase between 5 to 10 degrees if we continue on our present path.

Global warming is already disrupting food production, harming human health, increasing drought and variability in water supplies and causing more extreme and expensive storms, floods and fires. These impacts are predicted to become more severe and expensive the longer we wait.

Some Montana political leaders ignore the scientific findings about climate change. They say: “I’m not a scientist so I cannot be sure.” We are scientists and let us be clear: the scientific evidence that Earth’s climate is warming is overwhelming.

We need solutions commensurate with the gravity of the issue at hand. The EPA’s Clean Power Plan is one of those solutions. It will limit carbon pollution from the largest sources — power plants — for the first time. It is a necessary step to help avoid catastrophic climate change.

The good news? Innovations in clean energy technology show that viable and affordable solutions exist. Our leaders should use the extensive scientific evidence to enact appropriate policy solutions, both to limit carbon pollution and promote energy conservation and clean energy. They should support the proposal to reduce carbon pollution from power plants as well as support more clean energy jobs.

If 97 doctors out of 100 said that tests confirm that you have treatable cancer, would you follow the advice of the three doctors who weren’t 100 percent sure and suggested doing nothing? No. Now is the time to accept the overwhelming scientific research of global warming. We support the EPA’s actions to limit carbon pollution and urge our leaders to do the same.

The views stated are our personal views.

This column was submitted by Diana Six of Missoula, Ph.D., professor of forest entomology/pathology; Loren Acton of Bozeman, Ph.D., astro-geophysics; astronaut Eric Grimsrud, Ph.D., analytical and atmospheric chemistry; Steven Running of Missoula, Ph.D., Regents professor of ecology and co-recipient of the Nobel Peace Prize in 2007 as a member of the Intergovernmental Panel on Climate Change; Bruce Smith of Sheridan, Mont., Ph.D., zoology; and Kyle Strode of Helena, Ph.D., analytical chemistry.