The 8.2 ka event in northern Spain: timing, structure and climatic impact from a multi-proxy speleothem record

• Main Authors: Kilhavn, Hege, Couchoud, Isabelle, Drysdale, Russell N., Rossi, Carlos, Hellstrom, John, Arnaud, Fabien, Wong, Henri
• Format: Text
• Language: English
• Published: 2022
• Subjects: Greenland; Greenland ice core; ice core; North Atlantic
• Online Access: https://doi.org/10.5194/egusphere-2022-386; https://egusphere.copernicus.org/preprints/2022/egusphere-2022-386/

The 8.2 ka event is regarded as the most prominent climate anomaly of the Holocene and is thought to have been triggered by a meltwater release to the North Atlantic that was of sufficient magnitude to disrupt the Atlantic Meridional Overturning Circulation (AMOC). It is most clearly captured in Greenland ice-core records, where it is reported as a cold and dry anomaly lasting ∼ 160 years, from 8.25 ± 0.05 until 8.09 ± 0.05 ka (Thomas et al., 2007). It is also recorded in several archives in the North Atlantic region; however, its interpreted timing, evolution and impacts vary significantly. This inconsistency is commonly attributed to poorly constrained chronologies and/or inadequately resolved time series. Here we present a high-resolution speleothem record of early Holocene palaeoclimate from El Soplao Cave in northern Spain, a region pertinent to studying the impacts of AMOC perturbations on south-western Europe. We explore the timing and impact of the 8.2 ka event on a decadal scale by coupling speleothem stable carbon and oxygen isotopic ratios, trace element ratios (Mg <math xmlns="http://www.w3.org/1998/Math/MathML" id="M4" display="inline" overflow="scroll" dspmath="mathml"><mo>/</mo></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="8pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="57ee8123d9c9aefcf23d9c7f6463c158"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cp-18-2321-2022-ie00001.svg" width="8pt" height="14pt" src="cp-18-2321-2022-ie00001.png"/></svg:svg> Ca and Sr <math xmlns="http://www.w3.org/1998/Math/MathML" id="M5" display="inline" overflow="scroll" dspmath="mathml"><mo>/</mo></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="8pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="93e47eb16cb371fe6916d3191efc4f1d"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cp-18-2321-2022-ie00002.svg" width="8pt" height="14pt" ...