Graham Hancock on science: what the evidence says · JRE #1897
SUBJECT: SCIENCE
Not a true/false call. Every claim is logged with its sources; read the exhibits below.
2007, out comes this hypothesis with mainstream backing by mainstream scientists saying that it looks like there was a series, not just one impact, but multiple impacts all over the earth around 12,800 years ago that caused this cataclysm.
What the evidence says 01 / RECORD
The Younger Dryas Impact Hypothesis (YDIH), first proposed in 2007, holds that a cosmic impact or airburst around 12,800 years ago triggered abrupt cooling and contributed to megafaunal extinctions. It remains an actively disputed minority position within earth science rather than a mainstream consensus. A 2023 review in Earth-Science Reviews by a large team of impact-crater and Quaternary specialists concluded the hypothesis lacks reproducible, unambiguous impact evidence, while YDIH proponents published rebuttals in 2024 disputing that conclusion, and the exchange of refutations and counter-rebuttals continues in the peer-reviewed literature. Independent evidence once cited in support of an impact source has also weakened: a 2018-discovered crater beneath Greenland's Hiawatha Glacier, initially proposed by some researchers as a possible Younger Dryas impact site, was dated in 2022 to about 58 million years old, far too old to explain the Younger Dryas cooling roughly 13,000 years ago. Mainstream Quaternary science generally attributes the Younger Dryas cooling to changes in North Atlantic ocean circulation from glacial meltwater rather than a cosmic impact. Overall, Hancock's characterization of "mainstream backing by mainstream scientists" overstates the hypothesis's acceptance; it is best described as a contested, minority hypothesis still under active scientific dispute.