Rocks, rain and carbon dioxide help control Earth’s climate over thousands of years—like a thermostat —through a process called weathering. A new study led by Penn State scientists may improve our understanding of how this thermostat responds as temperatures change.
“Life has been on this planet for billions of years, so we know Earth’s temperature has remained consistent enough for there to be liquid water and to support life,” said Susan Brantley, Evan Pugh University Professor and Barnes Professor of Geosciences. “The idea is that silicate rock weathering is this thermostat, but no one has ever really agreed on its temperature sensitivity.”
Because many factors go into weathering, it has been challenging to use results of laboratory experiments alone to create global estimates of how weathering responds to temperature changes, the scientists said.
The team combined laboratory measurements and soil analysis from forty-five soil sites around the world and many watersheds to better understand weathering of the major rock types on Earth and used those findings to create a global estimate for how weathering responds to temperature.
Their model may be helpful for understanding how weathering will respond to future climate change, and in evaluating man-made attempts to increase weathering to draw more carbon dioxide from the atmosphere—like carbon sequestration.