Story URL: http://news.medill.northwestern.edu/chicago/news.aspx?id=230652
Story Retrieval Date: 3/3/2015 8:51:33 PM CST
“We need someplace to live while we’re looking for exoplanets.”
In this single sentence, Ray Pierrehumbert wrapped up the message and the passion of Northwestern University’s 4th Climate Change Symposium Friday.
“There’s a finite pool of money and a finite pool of political will,” Pierrehumbert said, referring to the U.S.’ short attention span on energy issues. “Put it all on CO2.”
That's because CO2 emissions - greenhouse gases emitted from fossil fuels - are driving climate change.
A geophysicist and climatologist from the University of Chicago, Pierrehumbert was joined by CO2 experts from around the U.S. and Canada at the symposium centered on “The Future of Carbon.”
“Most people who understand this issue understood that we’re not going to stop using fossil fuels tomorrow,” said Brad Sageman, organizer of Friday’s symposium and chair of NU's Department of Earth and Planetary Sciences. “We need to approach the use of fossil fuels with as intelligent strategies as possible to move to a no carbon future.”
Covering carbon storage, new technologies and the possibilities of renewable energy such as geothermal, the symposium’s speakers outlined strategies to meet energy demands but curb climate change due to fossil fuel emissions.
Carbon abatement strategies are increasingly important, because the extraction of oil and gas with fracking is propelling the U.S. into energy independence, said Michael Arthur, an expert in geology and geochemistry from Pennsylvania State University. This independence, Arthur said, has created an energy market where renewable resources often cannot compete, making it all the more important to combat carbon pollution in the near future.
One strategy to reduce the harm of carbon, the focus of Julie Jastrow’s research at Argonne National Laboratory, is to simply store carbon in vegetation and soil, where it can’t act as a greenhouse gas in the atmosphere.
“As part of [the carbon] cycle, a portion of the carbon gets spun off and stored in reservoirs” such as trees or soil, which hold onto carbon for long periods of time, Jastrow said. “The idea behind biological sequestration is we can take advantage of that and force a little bit more of it to spin off into these reservoirs.”
By converting disused and former agricultural land into planted reserves designed to maximize the amount of carbon trapped in biological material, Jastrow said climate change from carbon pollution can be reduced.
Recent climate reports issued by the Intergovernmental Panel on Climate Change, the White House and NASA have detailed a climate that is changing much faster than previously thought, elicited alarm bells throughout the scientific and political communities.
With CO2 accumulating in the atmosphere at 400 parts per million, a level unseen for at least 800,000 years, the resulting greenhouse effect has triggered a global warming trend, increasingly severe storms, droughts and flooding, and the melting of ice coverage in both polar regions. This rise in atmospheric CO2 is due to the human reliance on burning fossil fuels for energy, starting during the Industrial Revolution.
Martin Saar, a hydrogeologist at the University of Minnesota, explained another way of storing CO2, a way which would also help decrease our reliance on fossil fuels: geothermal energy.
By pumping CO2 into brine reservoirs deep underground, which is undrinkable water, the heat of the system rises with the pressure, Saar said. Then, by pumping the heated brine to the surface, it can be used to create energy without creating further CO2 pollution.
According to Saar, geothermal energy is one of the best energy forms available. It’s clean, it’s relatively easy to access, and its consistency allows it to serve as a base-load for power grids (something wind and solar energy cannot do).
“The problem with the U.S. is electricity is so cheap,” said Saar, “so heat pumps have a hard time competing.”
Scientists said we need a combination of strategies. No single one is the end-all solution to climate change.
“There’s not a lot of CO2 that can be used that way,” Saar said, pointing out the limitation of pumping carbon into a geothermal cycle. “In a closed loop, there’s only so much you can use.” Further, capturing CO2 at the point of creation is both difficult and expensive, Saar said, reducing incentives for companies to do it.
Similarly, biological sequestration is both limited by the amount of land dedicated to re-vegetation, Jastrow said, and the slow pace at which the carbon is captured in the plants and soil.
Nevertheless, Pierrehumbert said that the only way humans can avoid the worst climate change forecasts is by focusing on these CO2 mitigation strategies and incentivizing non-fossil fuel energy sources.
“CO2 is the only pollutant that remains for a millennium or more,” Pierrehumbert said.
The Institute for Sustainability and Energy at Northwestern and the Department of Earth and Planetary Sciences coordinated the symposium held on Northwestern's Evanston campus on Friday.
Text article by Luke Rague.