Bond event

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Gerard Bond proposed nine Bond events based on rock material piled with drift ice to the south

Bond events are presumed Holocene climatic fluctuations in the North Atlantic area with a period of 1470 ± 500 years.

definition

Temperature course in the Holocene

Bond events are climatic fluctuations that presumably occurred cyclically in the Holocene with an interval of about 1500 years. The climatic fluctuations were introduced into the scientific literature in 1997 by the geologist Gerard C. Bond , who was first described at the Lamont-Doherty Earth Observatory at Columbia University . His results were based on studies on petrological drift ice markers in the North Atlantic.

Bond events are to be distinguished from bond cycles . The latter is a periodicity of cold relapses of the late Pleistocene , also proposed by Gerard Bond , especially in the period 80,000-10,000 before today. The period of these cold relapses, known as the Heinrich Event, is about 6,000-15,000 years.

description

Drift ice can transport rock debris that sinks to the ocean floor after it has melted

Bond and his team examined sediments from the seabed of the North Atlantic. In different layers of their boreholes they found heaps of rock material that had probably been transported there by drift ice (material transported in this way is called ice rafted debris , or IRD for short ). They interpreted these frequency peaks as indicators of cold relapses in the North Atlantic in the periods to which the respective sediment layers could be assigned. In total, they identified nine frequency peaks, based on four drill cores, that occurred in the past 12,000 years. From these accumulations, they concluded that there were relapses in the North Atlantic.

The Bond events are possibly the interglacial counterpart of the glacial Dansgaard-Oeschger events . The magnitude of the fluctuations is approximately 15-20% of the glacial-interglacial temperature changes.

The existence of climatic fluctuations with a possible 1500-year rhythm is now recognized on the basis of ice cores for the last glacial . However, a continuation of these cycles into the Holocene is less certain. Bond et al. a. (1997) advocate a cyclicality of climate events with a period of 1470 ± 500 years for the North Atlantic area during the Holocene. From their point of view, many, possibly all, Dansgaard-Oeschger events are subject to a 1500-year rhythm and later events such as the Little Ice Age , the Misox fluctuation and the beginning of the Younger Dryas seem to be subordinate to the same rhythm.

The periods of accumulated drift-ice and iceberg sediments apparently correlate with abrupt weakenings in the Asian monsoons over the past 9,000 years . Moreover, they seem to have coincided with drought periods in the Middle East over the past 55,000 years , and this applies to both Heinrich events and Bond events. There are also many signs of changes in plant communities across North America , which also roughly follow a 1500-year cycle.

For reasons unknown up to now, the only distinctly pronounced Holocene Bond event is the Misox fluctuation; it shows a very clear temperature signal in ice cores from Greenland.

The 1500 year cycle shows non-linear properties as well as stochastic resonance ; This means that not every event is identical with an outstanding climate event, only some actually come to the fore as such in environmental history.

The causes and determinants of the 1500 year cycle are currently being investigated, with research focusing primarily on variations in the solar constant and redistributions in atmospheric circulation.

List of bond events

Most Bond events do not have a clear climate signal - some coincide with periods of cooling, while others correlate in areas with periods of drought.

number Time ( BP ) Remarks
0 ≈0.5 ka *) See Little Ice Age ;
1 ≈1.4 ka is associated with episodes of the early Middle Ages characterized as cool (→ pessimum of the migration period );
2 ≈2.8 ka Early 1st millennium BC BC Drought in the Eastern Mediterranean , possibly leading to the demise of the Late Bronze Age cultures;
3 ≈4.2 ka See 4.2 kilo-year event ; Collapse of the Akkadian Empire and the Old Kingdom of Egypt;
4th ≈5.9 ka See Piora fluctuation I ; End of the pre-ceramic Neolithic B and invasion of nomadic shepherds in the Middle East;
5 ≈8.2 ka See Misox Variation ;
6th ≈9.4 ka See Erdalen event : Glacier advances in Norway and a cold phase in China;
7th ≈10.3 ka Beginning of arable farming (grain cultivation) in the Middle East
8th ≈11.15 - 11.3 ka See Preboreal Variation ; Transition from the Younger Dryas to the Boreal ;
*)ka: kilogram year - d. H. Thousands of years before 1950 (BP)

See also

Individual evidence

  1. ^ A b c Frank M. Chambers: Bond Events . In: John A Matthews (Ed.): Encyclopedia of Environmental Change . SAGE, 2013, ISBN 978-1-4462-6488-1 .
  2. ↑ G. Bond et al: A Pervasive Millennial-Scale Cycle in North Atlantic Holocene and Glacial Climates . In: Science . tape 278, 5341 , 1997, pp. 1257-1266 .
  3. ↑ G. Bond et al: Persistent Solar Influence on North Atlantic Climate During the Holocene . In: Science . tape 294, 5549 , 2001, pp. 2130-2136 .
  4. ↑ Christopher J. Caseldine, Frank M. Chambers: Bond Cycles . In: John A Matthews (Ed.): Encyclopedia of Environmental Change . SAGE, 2013, ISBN 978-1-4462-6488-1 .
  5. ↑ Wanner, Olga Solomina , Martin Grosjean, Stefan P. Ritz, Markéta Jetel: Structure and origin of Holocene cold events . In: Quaternary Science Reviews . October 2011, doi : 10.1016 / j.quascirev.2011.07.010 .
  6. ↑ Olaf Elicki, Christoph Breitkreuz: The development of the system earth . Springer, 2016, ISBN 978-3-662-47192-0 , pp. 267 .
  7. ↑ Heinz Wanner: Climate and People - A 12,000-year history . Haupt, 2016, ISBN 978-3-258-07879-3 , pp. 120-124 .
  8. ^ GC Bond, W. Showers, M. Elliot, M. Evans, R. Lotti, I. Hajdas, G. Bonani, S. Johnson: The North Atlantic's 1-2 kyr Climate Rhythm: Relation to Heinrich Events, Dansgaard / Oeschger Cycles and the Little Ice Age. In: Geophysical Monograph Series. 112, 1999, pp. 35-58.
  9. ↑ Anil K. Gupta, David M. Anderson, Jonathan T. Overpeck: Abrupt changes in the Asian southwest monsoon during the Holocene and their links to the North Atlantic Ocean . In: Nature . tape 421, 6921 , 2003, pp. 354-357 .
  10. ↑ Yongjin Wang et al: The Holocene Asian Monsoon: Links to Solar Changes and North Atlantic Climate . In: Science . tape 308, 5723 , 2005, pp. 854-857 .
  11. ↑ Yuval Bartov, Steven L. Goldstein, Mordechai Stein, Yehouda Enzel: Catastrophic arid episodes in the Eastern Mediterranean linked with the North Atlantic Heinrich events . In: Geology . tape 31, 5 , 2003, pp. 439-442 .
  12. ^ Adrian G. Parker: A record of Holocene climate change from lake geochemical analyzes in southeastern Arabia . In: Quaternary Research . tape 66.3 , 2006, pp. 465-476 .
  13. ^ André E. Viau et al: Widespread evidence of 1,500 yr climate variability in North America during the past 14,000 yr . In: Geology . tape 30, 5 , 2002, pp. 455-458 .
  14. ^ John D. Cox: Climate Crash: Abrupt Climate Change and What It Means for Our Future . Joseph Henry Press, Washington DC 2005, ISBN 0-309-09312-0 , pp. 150-155 .
  15. ↑ Keliang Zhao et al .: Climatic variations over the last 4000 cal yr BP in the western margin of the Tarim Basin, Xinjiang, reconstructed from pollen data . In: Palaeogeography, Palaeoclimatology, Palaeoecology . tape 321–322 , 2012, pp. 16-23 .
  16. ↑ Samuli Helama, Phil D Jones, Keith R Briffa: Dark Ages Cold Period: A literature review and directions for future research . In: The Holocene . February 2017, doi : 10.1177 / 0959683617693898 .
  17. ^ Barry Weis: The decline of Late Bronze Age civilization as a possible response to climatic change . In: Climate Change . tape 4, 2 , 1982, pp. 173-178 .
  18. ↑ D. Kaniewski include: Middle East coastal ecosystem response to middle-to-late Holocene abrupt climate changes . In: PNAS . tape 105,37 , 2008, pp. 13941-13946 .
  19. ↑ D. Kaniewski include: Late second-early first millennium BC abrupt climate changes in coastal Syria and Their possible significance for the history of the Eastern Mediterranean . In: Quaternary Research . tape 74, 2 , 2010, pp. 207-215 .
  20. ↑ Ann Gibbons: How the Akkadian Empire Was Hung Out to Dry . In: Science . tape 261, 5124 , 1993, pp. 985 .
  21. ^ Jean-Daniel Stanley et al: Nile flow failure at the end of the Old Kingdom, Egypt: Strontium isotopic and petrologic evidence . In: Geoarchaeology . tape 18, 3 , 2003, pp. 395-402 .
  22. ↑ Svein Olaf Dahl et al .: Timing, equilibrium-line altitudes and climatic implications of two early-Holocene glacier readvances during the Erdalen Event at Jostedalsbreen, western Norway . In: The Holocene . tape 12, 1 , 2002, pp. 17-25 .
  23. ↑ Zhou Jing, Wang Sumin, Yang Guishan, Xiao Haifeng: Younger Dryas Event and Cold Events in Early-Mid Holocene: Record from the sediment of Erhai Lake . In: Advances in Climate Change Research . 3, Suppl. 2007, p. 1673-1719 .
  24. ↑ Harriet D. Allen: Response of past and present Mediterranean ecosystems to environmental change . In: Progress in Physical Geography . tape 27, 3 , 2003, pp. 359-377 .