Letters from the West

Idaho scientists explain why 97 percent say humans cause warming

The people whose research and knowledge inform the extension agents, water managers, foresters, farmers and other businesses about Idaho’s climate came to the Capitol Wednesday to talk about climate change.

Kerrie Weppner, a geology professor at Boise State University, explained the world history of warming over hundreds of centuries that scientists like her all understand, because they have multiple sources of data including ice cores with bubbles of ancient atmosphere. She explained how the levels of carbon dioxide correspond with past warming periods and how previous scientists had developed a universally accepted baseline of natural variation.

Then she showed how, in the 20th century, carbon dioxide levels rose beyond the natural baseline with molecules chemists identified from the burning of fossil fuels. As carbon dioxide and other greenhouse gases rose in the atmosphere, less heat escaped into deep space.

The earth has been heating up throughout the second half of the 20th Century, a fact that today almost no one on either side of the political debate disputes, even when they disagree about the cause.

Other scientists measuring changes in natural factors such as plate tectonics, changes in earth’s orbit and solar radiation have ruled them out as a cause of the warming. That’s why a concensus of world scientists say “it’s extremely likely” the current rapid climate change they have observed is human-caused with the burning of fossil fuels.

BSU Geosciences professor Jen Pierce offered an analogy on how certain 97 percent of scientists are of that fact: It’s like saying “it’s extremely likely” that Cleveland Cavaliers basketball star LeBron James is a better player than any of the 500 people in the Capitol’s Lincoln Auditorium.

But despite scientists’ certainty, the public doesn’t even believe that scientists believe that climate change is human caused. That frustrates Pierce and the other scientists at Idaho’s universities, who share the recognition of what the data shows.

“There is not debate on this in the scientific community at all,” Pierce said.

But there is great political debate, and widespread denial among mostly Republican political leaders that the climate change they see is tied to carbon dioxide. They argue, as the new Environmental Protection Agency Administrator Scott Pruitt did March 9, that CO2 is not a “primary contributor” to climate change.

That position allows Pruitt, the Trump administration and the Idaho congressional delegation to reject the worldwide political and financial consensus to move away from burning coal, oil and gas.

University of Idaho geography professor John Abatzoglou explains what that would mean to Idaho. If we do nothing, temperatures are expected to rise on average 10 degrees above what they are today by the end of the century. That would make Boise’s climate like that of Fresno, Calif., today. We would have a significantly smaller snowpack than we have today, even earlier runoffs than we’re seeing now, lower late summer river flows and even hotter and more frequent fires.

Idaho lawmakers have debated this year whether climate change should be taught in our schools. They have avoided talking about it in regular committee business.

That’s why Boise Democratic Rep. Ilana Rubel pushed for the Wednesday hearing and why Environment, Energy and Technology Committee Chairman Dell Raybould allowed the hearing, even though he himself doesn’t believe Idaho’s scientists.

If the scientists’ message was not political, the hearing clearly was. Democrats sat behind the speakers, demonstrating their support. The hearing attracted more than 650 people to the auditorium and overflow rooms, not just to learn but also to show their support.

To his credit, Raybould stayed through a significant part of the scientists’ talks. Even if he or you don’t want to take steps to reduce greenhouse gases, we all will have to continue to adapt our lives to these changes.

Politics will catch up to those who don’t.

Rocky Barker: 208-377-6484, @RockyBarker