Preboreal oscillation
The preboreal oscillation (PBO) was a short cooling period within the preboreal stage of the Holocene epoch.
Definition[edit]
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[edit]
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]
References[edit]
- ^ 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.
- ^ Behre, Karl-Ernst (1978). "Die Klimaschwankungen im europäischen Präboreal". Petermans geographische Mitteilungen. 2: 97–102.
- ^ 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.
- ^ Zoller, H. (1960). "Pollenanalytische Untersuchungen zur Vegetationsgeschichte der insubrischen Schweiz". Denkschriften der Schweizerischen Naturforschenden Gesellschaft. 83: 45–156.
- ^ 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.
- ^ 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.
- ^ 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.
- ^ 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.
- ^ 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.
- ^ 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.
- ^ 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]]