Emphasis – November 16
10:45 am
Fri November 16, 2012

The Science of Climate Change

Dr Eric Grimm
Dr Eric Grimm
Credit Rich Egger

For this week’s program, Rich Egger spoke with Dr Eric Grimm of the Illinois State Museum. They talked after Grimm gave the presentation “The Science of Climate Change” as part of the Second Sunday Science Series at Dickson Mounds Museum.

The US EPA says earth’s average temperature is expected to rise 2 to 11.5 degrees during the next 100 years. That would bring average global temperatures to levels not seen for at least 2 million years.

Grimm emphasized you cannot ascribe a single storm – such as Hurricane Sandy – to climate change, but it’s clear the frequency and power of such storms has increased.

He also pointed out there was a tremendous drought in the southern plains last year and another one in the Midwest this year.  In addition, sea levels increased eight inches during the 20th Century.

“Even if Sandy was the same intensity of a storm 50 years ago, its effect is going to be greater because of the sea level rise,” Grimm said.

The EPA reports average sea level worldwide is projected to rise up to two feet by the end of this century. This rise would eliminate approximately 10,000 square miles of land in the United States.

Grimm said another issue is the melting of the arctic permafrost, which stores huge amounts of carbon.

“And when that melts, it decomposes first into methane and then into carbon dioxide. So as the arctic is warming -- and the greatest warming globally is in the arctic – the permafrost is melting and that is releasing methane and carbon dioxide into the atmosphere.”

That cycle is referred to as “positive feedback.” Basically, greenhouse gases increase temperatures and increased temperatures lead to more greenhouse gases.

It’s not known if the potential exists for a huge amount of methane to be released in a short period of time, but Grimm said the consequences could be dire if that does happen.

“When it’s happened in the past there have been tremendous global warming incidents with extinction of species around the world.”

Grimm would like to see the US make a much greater investment in the research and development of alternative energy sources such as wind, solar, and fusion energy. He said nuclear power might be a viable option in the short term because it does not release greenhouse gases, though it poses a different set of challenges with nuclear waste.

He believes western Europe and the US are beginning to reduce fossil fuel consumption, but China and India continue to build new coal power plants and emit more greenhouse gases.

“I was in China recently. You can hardly breathe because the air is so polluted. Your eyes burn. It smells like coal smoke.”

Grimm is Curator and Chair of the Botany Section and Director of the Landscape History program at the Illinois State Museum. He’s studied the vegetation and climate history of the upper Midwest.