At a tree ring conference in the relatively treeless city of Tucson, Arizona, three scientists walk into a bar. The trio gets to talking, trying to explain a mysterious set of core samples from the Florida Keys. At some point, they come up with a harebrained idea: put the tree rings next to a seemingly unrelated dataset. Once they do, they notice something that no one has ever noticed before, a force of nature that helped shape modern human history and that is eerily similar to what’s happening on our planet right now. With help from pirates, astronomers and an 80-year-old bartender, this episode will change the way you look at the sun. (Warning: Do not look at the sun.) 

Special thanks to Scott St George, Nathaniel Millett, Michael Charles Stambaugh, Justin Maxwell, Clay Tucker, Willem Klooster, Kevin Anchukaitis


Reported by - Latif Nasserwith help from - Ekedi Fausther-Keeys and Maria Paz GutierrezProduced by - Maria Paz Gutierrez and Pat Walterswith help from - Ekedi Fausther-Keeys and Sachi MulkeyMixed by - Jeremy Bloomwith mixing help from - Arianne WackFact-checking by - Natalie Middletonand Edited by  - Pat Walters



Tree Story ( by Valerie TrouetSweetness and Power ( by Sidney Mintz

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