Chronological control and centennial-scale climatic subdivisions of the Last Glacial Termination in the western Mediterranean region

Imprint of seasonality changes on fluvio-glacial dynamics across Heinrich Stadial 1 (NE Atlantic Ocean)

“…Increasingly warm conditions on the northern Bay of Biscay are consistent with an intensified NAC and increasing SSTs as detected at regional scale (e.g., Caulle et al, 2013;Wary et al, 2015;Naughton et al, 2016;Hodell et al, 2013;Cacho et al, 1999;Martrat et al, 2014;Català et al, 2019). Also, warmer and more humid conditions are observed in the southern and western Iberian Peninsula (Fletcher and Sanchez Goñi, 2008;Naughton et al, 2009Naughton et al, , 2016Camuera et al, 2021;Fig.7) that may be attributed to the northward displacement of the polar front (Cayre et al, 1999;Naughton et al, 2009Naughton et al, , 2016.…”

“…Data acquired in the northern North Atlantic (Caulle et al, 2013;Wary et al, 2015), the western Iberian margin (Bard et al, 2000;Martrat et al, 2007;Eynaud et al, 2009;Hodell et al, 2013;Salgueiro et al, 2014;Naughton et al, 2016) and the Alboran Sea (Cacho et al, 1999;Martrat et al, 2014;Català et al, 2019) support this observation of warmer conditions at a regional scale. It appears accompanied by rapid forest development as documented in the western Mediterranean borderlands and NW Iberia at the onset of the B/A (Naughton et al, 2007(Naughton et al, , 2016Fletcher and Sanchez-Goñi, 2008;Combourieu-Nebout et al, 2009;Camuera et al, 2019Camuera et al, , 2021; Fig. 7) concomittant with increasing humidity, as also identified in speleothem records from southwestern Europe (Genty et al, 2006;Moreno et al, 2010;Jalut et al, 2010).…”

“…The oscillating pattern of 'Fleuve Manche' paleoriver runoff illustrated here by the different phases identified in HS1-a finds a striking echo in the environmental fluctuations from arid to more humid conditions in the Iberian Peninsula between 18.4 and 16.4 ka BP (Camuera et al, 2021: Fig. 7), with phases of higher runoff matching those of increased humidity in southern Europe.…”

“…Zaragosi et al, 2001). N. pachyderma percentages, coarse lithic grain concentrations CLG, magnetic susceptibility of bulk sediment (U em ; Grousset et al, 2000), and number of laminae are compiled with relative abundances of the main dinocyst species, percentages of C37:4 among C37 alkenones (red, Ménot et al, 2006) Composite Relative Sea Level (RSL) curve (Lambeck et al, 2014) with identified K-MWP at 19 ka BP and MWP-1A at ~14.6 ka BP, July Insolation curve at 65°N (Berger and Loutre, 1991), δ 18 O NGRIP record (GICCO05; Svensson et al, 2008), 231 Pa/ 230 Th signal (Ng et al, 2018), N. pachyderma percentages (blue, this study; red dotted line for the core MD95-2002 (Zaragosi et al, 2001)), H/A ratio (blue, this study; and reversed for comparison along the 231 Pa/ 230 Th signal), Runoff events (R) 4 and 5 (core MD95-2002, Toucanne et al, 2015, L. machaerophorum versus O. centrocarpum (Lmac/Ocen ratio, This study), L. machaerophorum versus I. minutum (Lmac/Imin ratio, This study), dinocyst-derived seasurface seasonality (SSTsummer-SSTwinter) and three-point moving average of Xerophyte and Mediterranean forest percentages from southern Spain (Camuera et al, 2021) as well as temperate forest percentages from the Alboran Sea (Fletcher and Sanchez Goñi, 2008). The proposed comparison respects dating uncertainties and strong reservoir age impacts at that time may be responsible for generating temporal offsets between records.…”

“…Overall cold and dry conditions are observed in the southern and western Iberian Peninsula, with a strong reduction of the Mediterranean and temperate forests (Fletcher and Sanchez Goñi, 2008;Naughton et al, 2016;Camuera et al, 2021;Fig.7) and a notable increase of xerophytic taxa (i.e., steppic taxa) (Camuera et al, 2021;Fig.7).…”