If interactions among volcanic emissions, acid rain, and rock weathering control climate, then there should be links between these geological events and global temperatures in the distant past. In 1983, a trio of scientists from Yale, the University of Florida, and Penn State tried to test that idea. Robert Berner, Antonio Lasaga, and Robert Garrels looked at the geological proxies for volcanic activity, acid rain, rock weathering, and other parts of the long-term carbon cycle in the rock record from 500 million years ago to the present.
