Secrets of Warming World Revealed in Arctic Mud

To learn more about what a warming world might look like, Yarrow Axford digs deep into Arctic mud. From lake-bottom sediment cores, Axford can understand environmental changes that occurred with past climate change.

“There are a lot of biological tracers in lake mud that can tell you about past environments,” said Axford, an assistant professor of Earth and planetary sciences who spent last August taking sediment cores in Greenland, thanks to funding from the Initiative for Sustainability and Energy at Northwestern (see "Seeking Sustainability," winter 2011). Insects, for example, are preserved in the mud and are powerful indicators of past temperature, “and we’re always very curious about what temperatures were in the past.

“The Arctic is a part of our planet that’s changing really rapidly right now,” Axford added, “so we’d like to understand how unusual those changes are if you look at a long-term context. Whenever the planet’s climate has changed in the past, the Arctic has generally changed a lot more than the planet on average. To extrapolate that to the future, if we warm globally, the Arctic will warm more than the rest of the globe, glaciers will respond to that, and that has implications for sea level everywhere.”

To bring the latest information on climate change to campus, Axford has helped to assemble a lineup of researchers to speak on impacts and solutions at the Northwestern Climate Change Symposium, co-sponsored by ISEN, the Department of Earth and Planetary Sciences and the Program in Environmental Policy and Culture. Speakers at the March 8 symposium, which is free and open to the public, will include architects Adrian Smith and Gordon Gill; Harvard Medical School’s Aaron Bernstein, who will address Chicago-area health impacts of climate change; and Richard Alley, a Penn State glaciologist who is host of PBS’s Earth: The Operator’s Manual.

“It’s hard for people to know where to go to get reliable facts on climate change,” said Axford. “We want to give the Northwestern community a chance to learn about these issues and to talk directly with researchers.”