Editing Younger Dryas (section)

=== Younger Dryas impact hypothesis ===
The [[Younger Dryas impact hypothesis]] (YDIH) attributes the cooling to the impact of a disintegrating comet or asteroid.<ref name="Powell2022">{{Cite journal |last=Powell |first=James Lawrence |date=January 2022 |title=Premature rejection in science: The case of the Younger Dryas Impact Hypothesis |journal=Science Progress |language=en |volume=105 |issue=1 |pages=003685042110642 |doi=10.1177/00368504211064272 |issn=0036-8504 |pmc=10450282 |pmid=34986034}}</ref> Because there is no [[impact crater]] dating to the Younger Dryas period, the proponents usually suggest the impact had struck the [[Laurentide ice sheet]], so that the crater would have disappeared when the ice sheet melted during the Holocene,<ref name="Gramling2021" /> or that it was an airburst, which would only leave micro- and nanoparticles behind as evidence.<ref name="Powell2022" /> Most experts reject the hypothesis, and argue that all of the microparticles are adequately explained by the terrestrial processes.<ref name="Holliday2023">{{Cite journal |last1=Holliday |first1=Vance T. |last2=Daulton |first2=Tyrone L. |last3=Bartlein |first3=Patrick J. |last4=Boslough |first4=Mark B. |last5=Breslawski |first5=Ryan P. |last6=Fisher |first6=Abigail E. |last7=Jorgeson |first7=Ian A. |last8=Scott |first8=Andrew C. |last9=Koeberl |first9=Christian |last10=Marlon |first10=Jennifer R. |last11=Severinghaus |first11=Jeffrey |last12=Petaev |first12=Michail I. |last13=Claeys |first13=Philippe |date=December 2023 |title=Comprehensive refutation of the Younger Dryas Impact Hypothesis (YDIH) |journal=Earth-Science Reviews |language=en |volume=247 |pages=104502 |doi=10.1016/j.earscirev.2023.104502|bibcode=2023ESRv..24704502H }}</ref> For instance, mineral inclusions from YD-period sediments in Hall's Cave, Texas, have been interpreted by YDIH proponents as extraterrestrial in origin, but a paper published in 2020 argues that they are more likely to be volcanic.<ref name="Sun2020" /> Opponents argue that there is no evidence for massive wildfires which would have been caused by an airburst of sufficient size to affect the thermohaline circulation,<ref name="Gramling2021">{{Cite news |last=Gramling |first=Carolyn |name-list-style=vanc |date=2018-06-26 |title=Why won't this debate about an ancient cold snap die? |url=https://www.sciencenews.org/article/younger-dryas-comet-impact-cold-snap |url-status=live |archive-url=https://web.archive.org/web/20210805112551/https://www.sciencenews.org/article/younger-dryas-comet-impact-cold-snap |archive-date=2021-08-05 |access-date=2023-02-23 |work=[[Science News]] |language=en-US}}</ref> [[Mineralogy|mineralogical]] and [[Geochemistry|geochemical]] evidence<ref>{{Cite journal |last=Jaret |first=Steven J. |last2=Scott Harris |first2=R. |date=2022-03-25 |title=No mineralogic or geochemical evidence of impact at Tall el-Hammam, a Middle Bronze Age city in the Jordan Valley near the Dead Sea |url=https://www.nature.com/articles/s41598-022-08216-x |journal=Scientific Reports |language=en |volume=12 |issue=1 |pages=5189 |doi=10.1038/s41598-022-08216-x |issn=2045-2322}}</ref> or for simultaneous human population declines and mass animal extinctions which would have been required by this hypothesis.<ref name="Holliday2023" />