What Cliffs Near America’s Earliest Settlements Tell Us About Climate Change

Scientists learn about Earth’s future climate by looking at geological records from the past. About 3 million years ago, most of the east coast of the United States was under water. Sediments collected on the ocean floor show that the ocean environment was warmer and supported more species back then. Some of these sediments are now exposed above water as cliffs along the James River near colonial Jamestown in southeastern Virginia. Tiny fossils and other evidence in these sediments, which we call the Yorktown Formation, show us how the environment and ecosystems were affected by global warming in the past, and they hold many clues as to what Earth may look like in the future.