**Jeremy Shakun** discusses how information about ancient climate cycles is preserved in stalactites and stalagmites (speleothems) in Arctic caves, and how scientists gather and analyze that very precise archive. He also explains other types of climate data, such as marine cores, Antarctic ice cores, glacial boulders, and tree rings.
**Jeremy Shakun** is an Assistant Professor in the Dept. of Earth & Environmental Sciences at Boston College. His research focuses on patterns and causes of climate change over the millennia. He received his PhD in geology from Oregon State University in 2010, and then was a postdoctoral Fellow at Boston University, Woods Hole Oceanographic Institution, Harvard University, Lamont Doherty Earth Observatory. He joined the faculty of Boston College in 2013. Dr. Shakun is a recipient of the EGU Climate Division Outstanding Young Scientist Award.