Preboreal oscillation

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The preboreal oscillation (PBO) was a short cooling period within the preboreal stage of the Holocene epoch.

Contents

Definition

Based on evidence from pollen, early Holocene cooling periods have been discovered already from the 1960s on. Locally, they were referred to as ‘Friesland Oscillation’ (Denmark [1] ), ‘Youngest Dryas’ (Germany [2] ), ‘Rammelbeek Phase’ (Netherlands [3] ), and ‘Piottino Oscillation’ (Switzerland [4] ). The term "preboreal oscillation" was derived from attempts to synchronize these events. [5] [6]

Dating

The greenland ice cores record a distinct decline in stable oxygen isotope data dated to 11 650–11 270 ice layer a BP (11 700–11 320 b2k) with the coldest part between 11 470 and 11 350 ice layer a BP (11 520–11 400 b2k) labelled as the ‘11.4 ka event’. [7]

In lake sedimentary records, the exact timing and duration of the PBO remain uncertain because of dating uncertainties due to two early Holocene radiocarbon plateau and unclear proxy evidence. [8] [9] Two ash layers derived from volcanic eruptions are frequently used as time markers for the PBO: the Askja-S and Hässeldalen tephras shortly before and after the event. [10] The ages of these layers were constrained to 11.228 ± 226 cal a BP and 11.380 ± 216 cal a BP, framing the cold event to a maximum duration of 152 +11/-8 years by varve counting. [11]

Related Research Articles

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<span class="mw-page-title-main">Last Glacial Period</span> Period of major glaciations of the northern hemisphere (115,000–12,000 years ago)

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<span class="mw-page-title-main">Varve</span> Annual layer of sediment or sedimentary rock

A varve is an annual layer of sediment or sedimentary rock.

Before Present (BP) years, also known as "time before present" or "years before present (YBP)", is a time scale used mainly in archaeology, geology, and other scientific disciplines to specify when events occurred relative to the origin of practical radiocarbon dating in the 1950s. Because the "present" time changes, standard practice is to use 1 January 1950 as the commencement date (epoch) of the age scale. The abbreviation "BP" has been interpreted retrospectively as "Before Physics", which refers to the time before nuclear weapons testing artificially altered the proportion of the carbon isotopes in the atmosphere, which scientists must now account for.

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<span class="mw-page-title-main">Oldest Dryas</span> Abrupt climatic cooling event during the last glacial retreat

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<span class="mw-page-title-main">Tephrochronology</span> Geochronological technique

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<span class="mw-page-title-main">Carbajal Valley</span> Landform of the Fuegian Andes in southern Argentina

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<span class="mw-page-title-main">Llanquihue glaciation</span> Last glacial period in southern Chile

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<span class="mw-page-title-main">Geological event</span> Earth

A geological event is a temporary and spatially heterogeneous and dynamic (diachronous) happening in Earth history that contributes to the transformation of Earth system and the formation of geological strata. Event stratigraphy was first proposed as a system for the recognition, study and correlation of the effects of important physical or biological events on the broader stratigraphical record.

References

  1. ↑ Iversen, Johs. (1973-12-31). "Geology of Denmark III: The Development of Denmark's Nature since the Last Glacial". Danmarks Geologiske Undersøgelse V. Række. 7: 1–126. doi: 10.34194/raekke5.v7.7020 . ISSN   2597-3037.
  2. ↑ Behre, Karl-Ernst (1978). "Die Klimaschwankungen im europäischen Präboreal". Petermans geographische Mitteilungen. 2: 97–102.
  3. ↑ Bos, Johanna A.A.; van Geel, Bas; van der Plicht, Johannes; Bohncke, Sjoerd J.P. (2007). "Preboreal climate oscillations in Europe: Wiggle-match dating and synthesis of Dutch high-resolution multi-proxy records". Quaternary Science Reviews. 26 (15–16): 1927–1950. Bibcode:2007QSRv...26.1927B. doi:10.1016/j.quascirev.2006.09.012.
  4. ↑ Zoller, H. (1960). "Pollenanalytische Untersuchungen zur Vegetationsgeschichte der insubrischen Schweiz". Denkschriften der Schweizerischen Naturforschenden Gesellschaft. 83: 45–156.
  5. ↑ Lowe, J. John; Ammann, B.; Birks, H. H.; Björck, S.; Coope, G. R.; Cwynar, L.; de Beaulieu, J.-L.; Mott, R. J.; Peteet, D. M.; Walker, M. J. C. (1994). "Climatic changes in areas adjacent to the North Atlantic during the last glacial-interglacial transition (14-9 ka BP): A contribution to IGCP-253". Journal of Quaternary Science. 9 (2): 185–198. Bibcode:1994JQS.....9..185L. doi:10.1002/jqs.3390090215.
  6. ↑ Björck, Svante; Kromer, Bernd; Johnsen, Sigfus; Bennike, Ole; Hammarlund, Dan; Lemdahl, Geoffrey; Possnert, Göran; Rasmussen, Tine Lander; Wohlfarth, Barbara; Hammer, Claus Uffe; Spurk, Marco (1996). "Synchronized Terrestrial Atmospheric Deglacial Records Around the North Atlantic". Science. 274 (5290): 1155–1160. Bibcode:1996Sci...274.1155B. doi:10.1126/science.274.5290.1155. ISSN   0036-8075. PMID   8895457. S2CID   45121979.
  7. ↑ Rasmussen, Sune O.; Bigler, Matthias; Blockley, Simon P.; Blunier, Thomas; Buchardt, Susanne L.; Clausen, Henrik B.; Cvijanovic, Ivana; Dahl-Jensen, Dorthe; Johnsen, Sigfus J.; Fischer, Hubertus; Gkinis, Vasileios; Guillevic, Myriam; Hoek, Wim Z.; Lowe, J. John; Pedro, Joel B. (2014). "A stratigraphic framework for abrupt climatic changes during the Last Glacial period based on three synchronized Greenland ice-core records: refining and extending the INTIMATE event stratigraphy". Quaternary Science Reviews. 106: 14–28. Bibcode:2014QSRv..106...14R. doi: 10.1016/j.quascirev.2014.09.007 . hdl: 2160/30436 . S2CID   55614771.
  8. ↑ Björck, S.; Rundgren, M.; Ingólfsson, Ó.; Funder, S. (1997). <455::AID-JQS316>3.0.CO;2-S "The Preboreal oscillation around the Nordic Seas: terrestrial and lacustrine responses". Journal of Quaternary Science. 12 (6): 455–465. Bibcode:1997JQS....12..455B. doi:10.1002/(SICI)1099-1417(199711/12)12:6<455::AID-JQS316>3.0.CO;2-S.
  9. ↑ Hoek, Wim Z.; Bos, Johanna A.A. (2007). "Early Holocene climate oscillations—causes and consequences". Quaternary Science Reviews. 26 (15–16): 1901–1906. Bibcode:2007QSRv...26.1901H. doi:10.1016/j.quascirev.2007.06.008.
  10. ↑ Wohlfarth, B.; Blaauw, M.; Davies, S. M.; Andersson, M.; Wastegård, S.; Hormes, A.; Possnert, G. (2006). "Constraining the age of Lateglacial and early Holocene pollen zones and tephra horizons in southern Sweden with Bayesian probability methods" (PDF). Journal of Quaternary Science. 21 (4): 321–334. Bibcode:2006JQS....21..321W. doi:10.1002/jqs.996. S2CID   67800522.
  11. ↑ Ott, Florian; Wulf, Sabine; Serb, Johanna; Słowiński, Michał; Obremska, Milena; Tjallingii, Rik; Błaszkiewicz, Mirosław; Brauer, Achim (2016). "Constraining the time span between the Early Holocene Hässeldalen and Askja-S Tephras through varve counting in the Lake Czechowskie sediment record, Poland: VARVE COUNTING BETWEEN THE HÄSSELDALEN AND AKSJA-S TEPHRA". Journal of Quaternary Science. 31 (2): 103–113. doi:10.1002/jqs.2844. S2CID   131161085.


[[Category:Quaternary]]

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