Editor's note: This is the first in a series of stories about how climate changed and is changing our world -- spiritually, physically -- as a result. Find more climate change coverage here.

Finding new solutions to problems caused by climate change is what David Keith, professor of applied physics at Harvard School of Engineering, works on every day. Keith, one of the featured speakers at the Nobel Conference at Gustavus Adolphus College on Sept. 25, 2019, noted that three earlier problems involving smog, DDT pesticides, and stratospheric ozone, were problems that inspired quick action and effective results.

Current efforts to solve climate change are falling short, he said.

“The reason that is has been so hard to make progress on climate change is that there’s money in politics, money from people who will lose under regulation,” Keith said. “There is money from big fossil fuels that has blocked action.”

He said one big surprise is the low cost and high capacity of modern industrial solar power, making it one of the key factors in decarbonization. However, that’s not enough.

“If we keep emitting carbon, climate change just keeps getting worse,” said Keith, who was named a Hero of the Environment in 2009 by Time Magazine. “Climate risk is proportional to cumulative emissions. When we bring emissions to zero, what we do is stop the problem from getting worse. We don’t make it better, we stop it from getting worse.”

There are ways of removing carbon from the air, he said, such as direct air capture and injecting the carbon into the ground, but efforts like that will only be effective after emissions have gone to zero.

“Some people think that removing carbon is easier than cutting emissions,” Keith said, “but that is a false understanding, because the hard part about cutting emissions is the political battle about who pays.”

Another idea for fighting climate change is solar geoengineering, Keith explained. This could involve adding aerosols to the stratosphere to reduce the energy imbalance, as long as this could be done evenly from the poles to the equator and across the hemispheres.

Dr. David Keith

“This looks like it is very cheap to do,” Keith said, “so that cost is not likely to be a big part of the decision. That means it is a risk decision. There are risks of doing it and risks of not doing it.”

Keith said many people do not want to think about climate change. It is a difficult problem with no simple solution, but much more research is needed, he said.

“The debate that we should be having is not about whether or not to do geoengineering, because that is not a decision that our generation is making,” Keith said. “That decision will get made in decades. My argument is that we should bring this out into the open. Sunlight is the best disinfectant. We should have an active, international research program.”

He said such a research program would give future generations the facts they need to make decisions about the use of new technologies.

“If we have no research program,” he said, “what it means is that people make decisions in ignorance.”