Geography and the Environment- Donald Meinig Undergraduate Lecture

Abstract: In the early 1900s, a creative astronomer named A. E. Douglass turned to tree rings to reconstruct sunspot  cycles. Through careful observation, he developed a method we call cross-dating to date tree rings to the calendar year, even for long dead trees. While Douglass failed to create a reliable history of sunspots, he recognized the potential to use tree rings to build long histories of past environments, date archeological sites and, with Willard Libby, calibrate the radiocarbon scale.

Over the 20th century, the field of dendrochronology contributed to major discoveries in a range of disciplines from archeology to climatology. By the turn of the 21st century, climate change became the overwhelming focus of paleoenvironmental studies and tree rings played a central role in confirming the reality of our changed climate. Ironically, with this discovery, dendrochronology also confirmed that the past is rapidly becoming no analogue for the future. With the climate debate settled, and the past seemingly not as relevant to understanding future climate, studies of past environments via tree rings and other environmental archives seemed destined for the dustbin of history.

In this talk, I challenge this view and argue that long tree ring records are a rare and precious paleoenvironmental archive that continue to yield new discoveries about the history of our planet, society, and the sun. Environmental archives continue to astound and need young passionate scientists to discover, safeguard, and mine them for the yet unknown histories they contain.