Mid-24th century BCE climate anomaly explained

The mid-24th century BCE climate anomaly is the period, between 2354 and 2345 BCE, of consistently reduced annual temperatures that are reconstructed from consecutive abnormally narrow, Irish oak tree rings. These tree rings are indicative of a period of catastrophically reduced growth in Irish trees during that period. This range of dates also matches the transition from the Neolithic to the Bronze Age in the British Isles and a period of widespread societal collapse in the Near East. It has been proposed that this anomalous downturn in the climate might have been the result of comet debris suspended in the atmosphere.^[1]

In 1997, Marie-Agnès Courty proposed that a natural disaster involving wildfires, floods, and an air blast of over 100 megatons occurred about 2350 BCE. This proposal is based on unusual "dust" deposits which have been reported from archaeological sites in Mesopotamia that are a few hundred kilometres from each other.^[2] In later papers, Courty subsequently revised the date of this event from 2350 BCE to 2000 BCE.^{[3] [4]}

Based only upon the analysis of satellite imagery, Umm al Binni lake in southern Iraq has been suggested as a possible extraterrestrial impact crater and possible cause of this natural disaster.^{[5] [6]} More recent sources have argued for a formation of the lake through the subsidence of the underlying basement fault blocks.^{[7] [8]} Baillie and McAneney's 2015 discussion of this climate anomaly discusses its abnormally narrow Irish tree rings and the anomalous dust deposits of Courty. However, this paper lacks any mention of Umm al Binni lake.^[9]

See also

• 4.2-kiloyear event, c. 2200 BCE
• Great Flood (China), c. 2300 BCE

Notes and References

1. Book: Baillie, Michael G. L. . 2007 . Tree-rings indicate global environmental downturns that could have been caused by comet debris . Comet/asteroid impacts and human society . 105–122 . Springer . Berlin, Heidelberg.
2. Courty . M.-A. . Causes and Effects of the 2350 BC Middle East Anomaly Evidenced by Micro-debris Fallout, Surface Combustion and Soil Explosion SIS Conference . https://web.archive.org/web/20070212122549/http://www.knowledge.co.uk/sis/abstract/courty.htm . dead . 2007-02-12 . Natural Catastrophes during Bronze Age Civilisations: Archaeological, Geological and Astronomical Perspectives . Society for Interdisciplinary Studies . Fitzwilliam College, Cambridge . 11–13 July 1997.
3. Courty . M.-A. . 1998 . The soil record of an exceptional event at 4000 BP in the Middle East . Peiser . B. J. . Palmer . T. . Bailey . M. E. . Natural catastrophes during Bronze Age civilisations: archaeological, geological, astronomical and cultural Perspectives . 93–108 . British Archaeological Reports S728 . Archaeopress . Oxford.
4. Book: Courty, M.-A. . 2001 . Evidence at Tell Brak for the Late EDIII/Early Akkadian Air Blast Event (4 kyr B.P.) . Oates . D. . Oates . J. . McDonald . H. . Excavations at Tell Brak . 2: Nagar in the Third Millennium B.C. . 367–372 . McDonald Institute for Archaeological Research . Cambridge.
5. Master . S. . Woldai . T. . The Umm al Binni structure in the Mesopotamian marshlands of southern Iraq, as a postulated late Holocene meteorite impact crater . Economic Geology Research Institute Information Circular . 382 . October 2004 . University of Witwatersrand . Johannesburg, South Africa.
6. Master . S. . Woldai . T. . 2007 . Umm al Binni structure, southern, as a postulated late Holocene meteorite impact crater: new satellite imagery, and proposals for future research . Bobrowsky . P. . Rickmann . H. . Comet/Asteroid Impacts and Human Society . Springer . Heidelberg, Germany.
7. Sissakian. Varoujan K.. Al-Bahadily. Hayder A.. November 2018. The geological origin of the Umm Al-Binni Lake within the Ahwar of Southern Mesopotamia, Iraq. Arabian Journal of Geosciences. en. 11. 21. 669. 10.1007/s12517-018-4004-6. 2018ArJG...11..669S . 135022453 . 1866-7511.
8. Sissakian . V. K. . Al-Ansari . N. . Adamo . N. . Geomorphology, Stratigraphy and Tectonics of the Mesopotamian Plain, Iraq: A Critical Review . Geotectonics . 1 January 2021 . 55 . 1 . 135–160 . 10.1134/S001685212101012X . 2021Geote..55..135S . 233403621 . 1 January 2022 . en . 1556-1976.
9. Baillie . Michael G. L. . Why we shouldn't ignore the mid-24th century BC when discussing the 2200–2000 BC climate anomaly . McAneney . Jonny . October 2015 . 7th Archaeological Conference of Central Germany October 23–26, 2014 . Halle, Germany . 2200 BC – A climatic breakdown as a cause for the collapse of the Old World? . 2 . 833–844.