Pro­fessor of Physics Ken Hayes gave a series of lec­tures this semester on global warming, climate change, and the con­se­quences for our earth. He sug­gested a number of solu­tions people can take to help with global warming. External Affairs

We will not have arctic ice within 10 years and might not have coral reefs due to global warming, according to Pro­fessor of Physics Ken Hayes.

In a three-part lecture series on climate change, Hayes, who has been studying global warming and climate change for 15 years, spoke to Hillsdale College stu­dents Feb. 4, Feb. 11, and Feb. 18 about the science behind climate change, the con­se­quences of global warming, and what can be done to change it.

In his first lecture, Hayes began with a com­parison of the average tem­per­ature of planets without atmos­phere to planets with atmos­phere. For planets without atmos­phere, there is an equation that pre­dicts tem­per­ature based on how much radi­ation from the sun they receive. For planets with atmos­phere, the equation is off because atmos­pheric gases increase surface tem­per­ature by redi­recting emitted infrared radi­ation back towards the surface.

“Nor­mally there’s a balance,” Hayes said, explaining that what keeps the earth’s tem­per­ature con­stant is a balance between the sun’s radi­ation coming in and the earth’s radi­ation going out. “But we have put a blanket around the earth, and we’ve made it harder for the radi­ation to exit the ground and get back into space.”

Though the green­house gases methane and carbon are only a fraction of the atmos­phere, Hayes said, they interact, absorb, and reflect back the infrared radi­ation from the surface, keeping the earth warm.

“Our problem is that we’ve been adding CO2 to the atmos­phere,” Hayes said.

In 1958, Charles Keeling, an American sci­entist, began pre­cisely mea­suring CO2 in the atmos­phere on the mountain Mauna Loa in Hawaii, and the CO2 was about 315 parts per million. Now it is 410 parts per million.

“We’ve changed the chem­istry 46 percent com­pared to what it was before we started burning coal around 250 years ago,” Hayes said.

The second lecture focused on the impacts of climate change. Hayes explained that the average tem­per­ature of the Earth is very sen­sitive. At the most recent glaciation 20,000 years ago, the Earth’s average tem­per­ature was 1.4 percent lower than today, or minus 4 degrees Celsius, and a tem­per­ature increase of that four degrees would raise sea levels by 70 meters. Since 1880, the global tem­per­ature dif­ference is 1.2 degrees Celsius, all due to CO2 emis­sions.

“Very few people under­stand just how much CO2 we’re putting in the atmos­phere,” Hayes said. “The world total for 2016 was 36.1 gigatons. The U.S. per capita was 16.1 tons, which is 35,000 pounds per year. That’s almost a 100 pounds per day that we put into the atmos­phere.”

In the town of Hillsdale alone, the CO2 emis­sions per household is 100,000 pounds per year.

The impacts of global warming include ocean warming, surface warming, melting ice, sea level rise, season length, ocean and atmos­pheric cur­rents, pre­cip­i­tation changes, drought, fire, and the most drastic result – the sixth extinction.

“There have been five major extinc­tions of life on the planet of all sorts,” Hayes said, “and we happen to be in the sixth one right now, and we’re the cause of the sixth one.”

Already the arctic sea ice is melting so rapidly that it cannot be saved in the next five years, and coral reefs are at risk. In 2016, 70 percent of the Great Barrier Reef was bleached and damaged because of the high tem­per­ature of the ocean.

“We’re not going to slow down, we’re not going to stop,” Hayes said. “We are driving the planet towards that sixth extinction.”

Hayes’ third lecture focused on solu­tions to reducing emis­sions. Hayes said the Inter­gov­ern­mental Panel on Climate Change esti­mated that humans would have to reduce emis­sions by about 10 percent per year until it reached zero between 2040 and 2055 to sta­bilize the tem­per­ature increase. Hayes pointed to climate sci­entist Peter Kalmus, who cut his CO2 emis­sions by 90 percent by biking, not flying, growing his own food, com­posting, buying fewer items, and going veg­e­tarian. Kalmus’ largest emission was flying — a 19-ton CO2 equiv­alent in 2010.

“It’s important to find out what your emis­sions are,” Hayes said, adding that what each indi­vidual faces in terms of need varies from region to region.

The problem, espe­cially for indus­tri­alized coun­tries, is how to reduce emis­sions and keep a wealthy lifestyle. Hayes said this can be done with non-CO2 emitting energy tech­nology, such as wind, hydro­electric, and nuclear energy. Changing mode of trans­portation, like switching from gasoline cars to electric cars, is an example of such tech­nology.

Indi­viduals can act in many ways, including edu­cating them­selves, voting for politi­cians who under­stand climate change, dis­cussing climate change, and reducing their own carbon foot­print.

But in the end, Hayes said, the biggest obstacle to global warming is human nature.

“In prin­ciple, it’s pretty simple; in practice, it’s epic,” Hayes said. “The chal­lenging aspect of global warming is getting people to act.”

Sophomore Caleb Ramette said in an email that he was skep­tical of the claims on humans causing climate change but that Hayes “pre­sented some con­vincing evi­dence indi­cating that we have at least con­tributed to global warming” in an unbiased and sci­en­tific manner.

“It was con­cerning to learn that the effects of climate change are delayed, so we might not see tem­per­a­tures rise until several years after we have caused them,” Ramette said. “Most of the dis­cus­sions on global warming are polit­i­cally charged, which means that there are agendas that drive those who deny or support claims on humans’ con­tri­bu­tions. It was nice to see actual facts pre­sented to support Dr. Hayes’ claims rather than just hear a list of buzz­words.”

Sophomore Isaac Warchol said in an email that prior to the lecture, he knew that humans were driving climate change, but he didn’t know how quickly the problem was advancing.

“Climate change is an an important issue that does not need to be a strictly political one,” Warchol said. “I think each person needs to reex­amine the issue from the stand­point of sci­en­tific data and apart from any pre­vious political con­vic­tions, and let that infor­mation guide their views about their own per­sonal behavior and public policy.”