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This is a file containing analytical and methodological details to build the depth age model El Cañizar de Villarquemado record.

The iconic climate archive of Tenaghi Philippon (TP), NE Greece, allows the study of short-term palaeoclimatic and environmental change throughout the past 1.3 Ma. To provide high-quality age control for detailed palaeoclimate reconstructions based on the TP archive, (crypto)tephra studies of a peat core ‘TP-2005’ have been carried out for the 0–130 ka interval. The results show that the TP basin is ideally positioned to receive tephra fall from both the Italian and Aegean Arc volcanic provinces. Two visible tephra layers, the Santorini Cape Riva/Y-2 (c. 22 ka) and the Campanian Ignimbrite (CI)/Y-5 (c. 39.8 ka) tephras, and six primary cryptotephra layers, namely the early Holocene E1 tephra from the Aeolian Islands (c. 8.3 ka), the Campanian Y-3 (c. 29 ka) and X-6 tephras (c. 109.5 ka), as well as counterpart tephras TM-18-1d (c. 40.4 ka), TM-23-11 (c. 92.4 ka) and TM-33-1a (c. 116.7 ka) from the Lago Grande di Monticchio sequence (southern Italy), were identified along with repeatedly redeposited Y-2 and CI tephra material. Bayesian modelling of the ages of seven of the primary tephra layers, 60 radiocarbon measurements and 20 palynological control points have been applied to markedly improve the chronology of the TP archive. This revised chronology constrains the age of tephra TM-18-1d to 40.90–41.66 cal ka BP (95.4% range). Several tephra layers identified in the TP record form important isochrons for correlating this archive with other terrestrial (e.g., Lago Grande di Monticchio, Sulmona Basin and Lake Ohrid) and marine (e.g., Adriatic Sea core PRAD 1-2 and Aegean Sea core LC21) palaeoclimate records in the Mediterranean region.

Although there are many Late-glacial (ca. 15 000-11 000 cal. yr BP) proxy climate records from northwest Europe, some analysed at a very high temporal resolution (decadal to century scale), attempts to establish time-stratigraphical correlations between sequences are constrained by problems of radiocarbon dating. In an attempt to overcome some of these difficulties, we have used a Bayesian approach to the analysis of radiocarbon chronologies for two Late-glacial sites in the British Isles and one in the Adriatic Sea. The palaeoclimatic records from the three sites were then compared with that from the GRIP Greenland ice-core. Although there are some apparent differences in the timing of climatic events during the early part of the Late-glacial (pre-14 000 cal. yr BP), the results suggest that regional climatic changes appear to have been broadly comparable between Greenland, the British Isles and the Adriatic during the major part of the Late-glacial (i.e. between 14 000 and 11 000 cal. yr BP). The advantage of using the Bayesian approach is that it provides a means of testing the reliability of Late-glacial radiocarbon chronologies that is independent of regional chronostratigraphical (climatostratigraphical) frameworks. It also uses the full radiocarbon inventory available for each sequence and makes explicit any data selection applied. Potentially, therefore, it offers a more objective basis for comparing regional radiocarbon chronologies than the conventional approaches that have been used hitherto.

Although there are many Late-glacial (ca. 15 000-11 000 cal. yr BP) proxy climate records from northwest Europe, some analysed at a very high temporal resolution (decadal to century scale), attempts to establish time-stratigraphical correlations between sequences are constrained by problems of radiocarbon dating. In an attempt to overcome some of these difficulties, we have used a Bayesian approach to the analysis of radiocarbon chronologies for two Late-glacial sites in the British Isles and one in the Adriatic Sea. The palaeoclimatic records from the three sites were then compared with that from the GRIP Greenland ice-core. Although there are some apparent differences in the timing of climatic events during the early part of the Late-glacial (pre-14 000 cal. yr BP), the results suggest that regional climatic changes appear to have been broadly comparable between Greenland, the British Isles and the Adriatic during the major part of the Late-glacial (i.e. between 14 000 and 11 000 cal. yr BP). The advantage of using the Bayesian approach is that it provides a means of testing the reliability of Late-glacial radiocarbon chronologies that is independent of regional chronostratigraphical (climatostratigraphical) frameworks. It also uses the full radiocarbon inventory available for each sequence and makes explicit any data selection applied. Potentially, therefore, it offers a more objective basis for comparing regional radiocarbon chronologies than the conventional approaches that have been used hitherto.

A multidisciplinary study (planktic and benthic foraminifera, pollen record, oxygen and carbon stable isotopes, alkenones, magnetic susceptibility) was carried out on several cores collected from the Central Mediterranean (Adriatic and Sicily Channel). The aim of the study was to examine the stratigraphy of the Early Holocene (pre-Boreal) interval at a high temporal resolution. The geochronological framework employed is based on Bayesian analysis of radiocarbon dates, tephra layers and geological constraints, integrated with oxygen isotope stratigraphy and planktic foraminifera ecostratigraphy, which provide independent methods for correlation. The interval between the end of the GS-1 (Younger Dryas) stadial and the lower boundary of an episode which we assign to Sapropel 1, reveals at least two oscillations, one of 1200 yrs duration (9.6-10.8 kyr B.P.), and the other of 200 yrs (9.2-9.4 kyr B.P.). These two relatively cold spells are characterised by a general decrease of warm planktic foraminifera species, and peaks in deep-dwelling species indicating winter mixing (G. inflata and G. truncatulinoides). The pollen-stratigraphic, stable isotope oxygen and alkenone records for the older and longer oscillation (9.6-10.8) suggest a complex period characterised initially by relatively humid conditions (10.5-10.8 kyr B.P) which give way to significantly drier conditions (by ca.10 kyr B.P.). Similar oscillations, of about the same age, have been previously published for the Tyrrhenian Sea as well as for Alboran Sea and Gulf of Cadiz, indicating that a large sector of the Mediterranean was influenced by the same forcing event. The characteristics of these two early Holocene oscillations are compared with two cold spells recorded in the Central Mediterranean that interrupt the GI-1 warm interval (Bolling-Allerod), and which are equated with GRIP oscillations GI-1b and GI-1d. This comparison revealed differences in paleoceanographic conditions between the Early Holocene and GI-1 oscillations. One of the biggest differences is the presence of winter mixing during the relatively colder pre-Boreal oscillations, suggesting that Adriatic deep water formed during these intervals. Conversely, the cold spells during GI-1, in contrast to the warmer episodes during this interstadial, suggest reduced deep water formation, which heralded the onset of the GS-1 (Y.D.) stadial.