Full Glacial Period Research Articles

New chronology of the deposits from the inner chambers of the Guanyindong cave, southwestern China

Guanyindong Cave is one of most important Palaeolithic sites in southwestern China, due to its presence of the earliest Levallois artifacts in East Asia, which was dated to two discrete periods at ∼160–170 thousand years ago (ka) and ∼70–80 ka, respectively, based on optical dating of the artifact-bearing sediments from the west entrance of the cave (Hu, et al., 2019a). There were five excavation pits at Guanyindong during the initial excavation seasons in 1960s, all of which have yielded abundant stone artifacts and fauna fossils. However, in contrast to the excavation pits at the west entrance whose chronology and lithic industry were intensively studied, the chronological frameworks of the excavation pits inside the cave chambers have not been established. Here we report optical dating results of sediment samples taken from two of the pits inside the cave (Profiles 2A and 3). We established Bayesian age models for the two profiles based on our new optical ages and the U-series ages obtained in previous studies. Our results indicate that the group B deposits in the main chambers of the cave accumulated between ∼200 ka and ∼100 ka. The chronology of the deposits from the inner chambers, together with those from the west entrance, provided a new age constraint for the Levallois artifacts from the site and suggested that hominins occupied the cave from ∼180 ka to ∼80 ka, spanning a full glacial and interglacial period (from MIS 6 to MIS 5).

New palaeontological evidence suggests an early Middle Pleistocene age for the lower levels of Sun Hole Cave, Cheddar, Somerset, UK

Sun Hole, a small fissure cave on the north side of Cheddar Gorge, Somerset, is best known as the site where late Upper Palaeolithic artefacts are associated with human and other mammal remains that immediately pre-date the Lateglacial interstadial. These remains from the upper levels (Unit I) overlie sediments (Unit II) that are thought to have accumulated during a full glacial period, below which are sediments (Unit III) attributed to an interglacial stage. The extinct land snail Retinella (Lyrodiscus) sp., which in Britain was only known from the Hoxnian Stage, had previously been recovered from Unit III. The interglacial at the base of the sequence was therefore assigned to the Hoxnian Stage (Marine Isotope Stage (MIS) 11, 424–374 kyr). Here we provide additional analyses of samples from Unit III, which as well as containing further Retinella (Lyrodiscus), also yielded a specimen of Monachoides incarnatus, its first record from the British Pleistocene. An associated assemblage of small mammals included a few that are rare in the British Pleistocene, such as birch mouse (Sicista cf. betulina) and garden dormouse (Eliomys quercinus). The vole Lasiopodomys gregaloides and the shrew Sorex (Drepanosorex) savini do not occur as late as the Hoxnian and therefore suggest an older age in the early Middle Pleistocene. The record from Sun Hole therefore has parallels with the well-known sequence from the upper Calcareous Member in the nearby cavern system at Westbury-sub-Mendip.

Orbital-scale vegetation-ocean-atmosphere linkages in western Japan during the last 550 ka based on a pollen record from the IODP site U1427 in the Japan Sea

Climate and vegetation in Japan are strongly influenced by the East Asian Monsoon (EAM) and the ocean environment of the Japan Sea. This study discusses the findings from a new pollen record from Integrated Ocean Drilling Program Site U1427, situated off the northern coast of the Honshu Island in western Japan, which allows for direct comparisons with other oceanographic proxies from this area. Our findings demonstrate the orbital-scale vegetation changes in this area and their land-ocean-atmosphere linkages during the last 550 ka. During surface-water freshening events in the Japan Sea, likely associated with colder water temperatures caused by the very low eustatic sea levels and the consequent isolation from the surrounding seas during the full-glacial periods, cold-cool conifer forests became dominant under the extremely dry pseudo-continental conditions in the Japanese islands. In contrast, temperate broadleaf forests increased rapidly when the surface-freshening events ended and a weak inflow of warm water began at the onset of deglaciation, in addition to the rapid atmospheric climate warming during termination periods. During the intermediate periods between the full interglacial to the full-glacial, the Tp ratio (pollen temperature index) increased in association with the summer insolation maxima caused by the Earth's precession cycle that coincide with Chinese stalagmite negative δ18O peaks, whereas Cryptomeria pollen abundance (high-precipitation index) increased in association with the winter insolation maxima. Those orbital-scale vegetation fluctuations were attributed to the changes in seasonal temperature and precipitation patterns, where were influenced by the EAM changes that were associated with seasonal insolation changes around the Japanese archipelago. Cryptomeria forests likely developed under cool and wet conditions throughout a year with low seasonal contrasts, whereas deciduous broadleaf forests increased under condition of high seasonality with cool summers and colder, drier winters. Alternating fluctuations between the Tp ratio and Cryptomeria pollen abundance following the insolation changes were typically observed after MIS 9 and are thought to have been affected by the periodicity shift in the EAM fluctuations across the Mid-Brunhes Event.

An improved chronology for the microscopic charcoal and pollen records from Anderson Pond, Tennessee, USA

Anderson Pond in eastern Tennessee is one of only a handful of sites in the interior southeastern US where researchers have developed pollen records that extend to the last full glacial period. Pollen data from the site have been widely used in regional syntheses and models of past vegetation and climate. Previous researchers either constructed age models that assumed continuous sedimentation from the Late Pleistocene to the present, and plotted pollen data by radiocarbon or calibrated ages (1976 core), or recognized the likelihood of hiatuses in the postglacial sediments, and plotted pollen data by depth (2007 cores). We present an improved chronology for the 1976 core based on prior delineation and dating of two hiatuses, and on new age modeling using AMS dates on macrofossils from cores collected in 2007. This new age model allows us to plot pollen and microscopic charcoal by age for the entirety of the record, and more accurately represents site history. Plotting pollen and charcoal assemblages by age using our new chronology highlights the long intervals of time that are missing from the postglacial record at Anderson Pond, while improving our ability to make use of proxy data from the fragmented sediments of this classic pollen site.

Glacial and interglacials in the Neotropics: a 130,000-year diatom record from central Panama

The last interglacial was the most recent time when temperatures were 1–2 °C above modern, but little is known of this period in the lowland Neotropics. Equally, data for the full glacial period are very limited. A detailed analysis of the period between ~ 137 and 100 ka was completed to provide a paleoecological history of the last interglacial in central Panama. Two additional fossil diatom records from the same depositional basin provided records of the glacial period. Diatom assemblages were compared across all cores and the dominant species of both glacial and interglacial periods was almost always Aulacoseira granulata. Other species, e.g. Aulacoseira agassizii, Achnanthidium minutissimum, Nitzschia amphibia, and Navicula radiosa, had distinctive patterns of abundance within the record, indicating a shallowing of the lake in the last millennia of MIS5e. The period between 119 and 108 ka witnessed the most change within the high-resolution portion of the record suggesting an increased lake level, with expanding lake margins. Other sediment cores collected within the caldera revealed the continued presence of a lake at El Valle through much of the glacial period, with shallowing evident at the time of the LGM. The changes in diatom assemblages at El Valle provide one of the oldest precipitation records from Central America tracking mean ITCZ position between the last interglacial and glacial periods. Furthermore, the evidence for both a wet interglacial and glacial period support palynological findings that the humid environments of Central Panama were not interrupted by glacial aridity.

Activation of a small ephemeral lake in southern Jordan during the last full glacial period and its paleoclimatic implications

AbstractPlayas, or ephemeral lakes, are one of the most common depositional environments in arid and semiarid lands worldwide. Playa deposits, however, have mostly been avoided as paleoclimatic archives because they typically contain exceptionally low concentrations of organic material, making14C dating difficult. Here, we describe a technique for concentrating organic matter in sediments for radiocarbon dating and apply it to playa sediments recovered from a 2.35 m sediment core from a small playa in southern Jordan. Based on14C ages of the organic concentrate fraction, the playa was active from ~29 to 21 ka, coincident with the last major high stand of Paleolake Lisan and wet conditions recorded by other paleoclimatic proxies in the southernmost Levant during the last full glacial period (35–20 ka). The timing and spatial pattern of these records suggests that the increased moisture was likely derived from more frequent and deeper eastern Mediterranean (EM) cyclones associated with the intensification of the westerlies. The presence of full glacial pluvial deposits in southern Jordan (29°N), and the lack of similarly aged deposits in the northern Arabian Peninsula to the south, suggests that the southerly limit of the incursion of EM cyclones during last full glacial period was ~28°N.

Refugial ecosystems in central Asia as indicators of biodiversity change during the Pleistocene–Holocene transition

Site-scale species richness (alpha diversity) patterns are well described for many present-day ecosystems, but they are difficult to reconstruct from the fossil record. Very little is thus known about these patterns in Pleistocene full-glacial landscapes and their changes following Holocene climatic amelioration. However, present-day central Asian ecosystems with climatic features and biota similar to those of the full-glacial periods may serve as proxies of alpha diversity variation through both space and time during these periods. We measured alpha diversity of vascular plants, bryophytes, macrolichens and land snails, as well as environmental variables, in 100-m2 plots located in forests and open habitats in the Russian Altai Mountains and their northern foothills. This region contains adjacent areas that possess climatic and biotic features similar to mid-latitude Europe for both the Last Glacial Maximum and contemporaneous Holocene ecosystems. We related alpha diversity to environmental variables using generalized linear models and mapped it from the best-fit models. Climate was identified as the strongest predictor of alpha diversity across all taxa, with temperature being positively correlated to number of species of vascular plants and land snails and negatively correlated to that of bryophytes and macrolichens. Factors important for only some taxa included precipitation, soil pH, percentage cover of tree layer and proportion of grassland areas in the landscape around plots. These results, combined with the high degree of similarity between the current Altai biota and dry-cold Pleistocene ecosystems of Europe and northern Asia, suggest that vascular plant and land snail alpha diversity was low during cold phases of the Pleistocene with a general increase following the Holocene climatic amelioration. The opposite trend probably existed for terricolous bryophytes and macrolichens.

Contrasting scaling properties of interglacial and glacial climates.

Understanding natural climate variability is essential for assessments of climate change. This is reflected in the scaling properties of climate records. The scaling exponents of the interglacial and the glacial climates are fundamentally different. The Holocene record is monofractal, with a scaling exponent H∼0.7. On the contrary, the glacial record is multifractal, with a significantly higher scaling exponent H∼1.2, indicating a longer persistence time and stronger nonlinearities in the glacial climate. The glacial climate is dominated by the strong multi-millennial Dansgaard–Oeschger (DO) events influencing the long-time correlation. However, by separately analysing the last glacial maximum lacking DO events, here we find the same scaling for that period as for the full glacial period. The unbroken scaling thus indicates that the DO events are part of the natural variability and not externally triggered. At glacial time scales, there is a scale break to a trivial scaling, contrasting the DO events from the similarly saw-tooth-shaped glacial cycles.

Glacigenic debris-flow deposits, Storfjorden Fan

Glacigenic debris-flow deposits (Laberg & Vorren 1995; Laberg et al. 2012) are the most prominent component of high-latitude trough-mouth fans (TMFs), which develop off fast-flowing ice streams which occupy cross-shelf troughs during full-glacial periods. Glacial erosion and sediment transport to the shelf edge are most effective during glacial maxima; debris-flow deposits therefore represent short periods of a very high input of glacigenic sediments to the continental slope when the ice front reaches the shelf break. Conversely, relatively limited amounts of mostly hemipelagic sediments accumulate on the continental slope during interglacial periods (Dowdeswell et al. 2002). Storfjorden TMF consists of three coalescent lobes (I–III) produced by three ice streams (Fig. 1a, b). It is dominated by an extensive network of gullies on the upper continental slope (Pedrosa et al. 2011; Lucchi et al. 2013) that do not cut back deeply into the continental shelf and are typically 5–20 km long (Fig. 1c, d). The gullies are nearly straight or have a low sinuosity, and are generally less than …

Glacigenic debris-flows observed in 3D seismic high-resolution seafloor imagery, Faroe–Shetland Channel, NE Atlantic

Glacigenic debris-flows represent successive mass-flow deposits that build out a prograding wedge of sediment beyond the grounding zone of an ice sheet (e.g. Laberg & Vorren 1995; King et al. 1998). A prograding sedimentary depocentre extending from the outer shelf to the upper slope has been observed in geophysical datasets from the West Shetland margin of the Faroe–Shetland Channel, NW of the UK in the NE Atlantic. Overlapping, glacigenic debris-flows comprise the Rona and Foula wedges and provide insight into the extent and stability of the northern sector of the British Ice Sheet during the last full-glacial period (Stoker & Varming 2011). The Rona and Foula sedimentary wedges dominate the West Shetland margin south of 61° N (Fig. 1a) and overlap to form an elongate, outer-shelf to upper-slope depocentre up to 300 m in thickness (Stoker & Varming 2011). Typically elongate and sinuous lobe-like landforms are observed on seafloor imagery (Fig. 1a), and form a stacked association of lobes in seismic-reflection profiles (Fig. 1f). The sedimentary lobes of the Rona Wedge occur in water depths from approximately 400 to 1000 m, partly cover the floor of the Faroe–Shetland Channel and infill part of the Judd Deeps (Fig. 1a). The lobes of …

Deep iceberg ploughmarks in the central Arctic Ocean

Ploughmarks from deep-drafted icebergs produced during full-glacial periods are found on the central Arctic Ocean seafloor down to approximately 1000 m below present sea level. Submarine ridge crests, for example the Lomonosov Ridge and Morris Jesup Rise, and plateaus such as the Yermak Plateau, are heavily ploughed. Different generations occur over a range of water depths and in different configurations. These range from single large ploughmarks to coherent systems of parallel ploughmarks forming a seafloor morphology that resembles mega-scale glacial lineations (MSGLs). The first discoveries of central Arctic Ocean iceberg ploughmarks at depths of c. 1000 m were made by geophysical mapping using side-scan sonar and sub-bottom profilers from ice-strengthened research vessels (Vogt et al. 1994), icebreakers (Jakobsson 1999) and submarines (Polyak et al. 2001). Lomonosov Ridge extends across the central Arctic Ocean from Greenland's northern continental slope to the slope of the East Siberian Sea (Fig. 1a). Iceberg ploughmarks were first mapped on the ridge crest ( c. 87° N, 145° E) with chirp sonar in 1996 (Jakobsson 1999). In this region of the Lomonosov Ridge, …

Nordvestfjord: a major East Greenland fjord system

Fjords are deep valleys that have been flooded by encroaching seawater after ice retreat (Syvitski et al. 1987). They are produced mainly by glacial erosion, with the ice sometimes exploiting pre-existing river systems or structural weaknesses. Fjords are found in mountainous terrain in all areas affected by large glaciers and ice sheets, both today and during full-glacial periods. They are therefore a distinctive landform indicative of past glacial activity. Nordvestfjord is a 140 km long fjord that is typically about 5 km wide with very steep walls (Fig. 1a–g). The mountains surrounding Nordvestfjord rise to over 2000 m. Several small branches join the fjord before it enters the much wider and shallower Hall Bredning, part of the Scoresby Sund fjord system in East Greenland (Fig. 1b) (Dowdeswell et al. 1994 a ). The distance from the head of the fjord to the outer coast of Greenland is about 300 km (Fig. 1b), making Scoresby Sund the largest fjord system in the world at 13 700 km2. The whole fjord system was occupied by ice during the Last Glacial Maximum (Dowdeswell et al. 1994 a ). Deglaciation of Scoresby Sund began about 16 …

A glacier-influenced turbidite system and associated landform assemblage in the Greenland Basin and adjacent continental slope

Evidence of the former extent and dynamics of the Greenland Ice Sheet is preserved on the continental margin of NE Greenland (Fig. 1). The continental shelf is incised by a number of deep (up to 500 m) cross-shelf troughs (Batchelor & Dowdeswell 2014; Arndt et al. 2015) (Fig. 1a), which are interpreted to have been occupied intermittently and eroded by marine-terminating ice streams during successive full-glacial periods (e.g. Dowdeswell et al. 2014). The outer continental shelf of NE Greenland was previously thought to have remained free of grounded ice during the Last Glacial Maximum (LGM) at around 20 ka, with the ice sheet restricted mainly to fjord and inner-shelf locations (Funder 1989; Funder & Hansen 1996; Bennike & Weidick 2001). However, recent geophysical and geological evidence, including streamlined submarine landforms and moraine ridges within several cross-shelf troughs, suggests that the Greenland Ice Sheet expanded across the outer-shelf beyond the NE Greenland coast, possibly to the shelf break, during the LGM (Evans et al. 2002, 2009; Winkelmann et al. 2010). Fig. 1. ( a ) Multibeam swath bathymetry of the Greenland Basin and adjacent continental slope beyond Kejser Franz Josef Trough (KFJT) and Norske Trough (NT). Dashed white lines show former ice-stream flow pathways in troughs across the continental shelf. Multibeam acquisition system Kongsberg-Simrad EM120. Frequency 12 kHz. Grid-cell size 100 m. Background bathymetry is from IBCAO v. 3.0. ( b ) Profile along the axis of the main channel in the Greenland Basin. VE×90. ( c ) Location of study area (red box; map from IBCAO v. 3.0). Dashed black lines bound major cross-shelf troughs. JMFZ, Jan Mayen Fracture Zone. Three smaller troughs are present between Kejser Franz Josef Trough and Norske Trough (Batchelor & Dowdeswell 2014). Evidence of past ice-sheet activity is not restricted to the continental shelf; landforms …

A subglacial landform assemblage on the outer shelf of M'Clure Strait, Canadian Arctic, ploughed by iceberg keels

M'Clure Strait in the Canadian Beaufort Sea (Fig. 1) is one of the largest cross-shelf troughs in the High Arctic, with a length of over 1000 km and a maximum cross-trough width of about 250 km (Batchelor & Dowdeswell 2014). It is thought to be the former location of a fast-flowing ice stream which drained the northwestern Laurentide Ice Sheet during the Late Wisconsinan, and probably a number of earlier Quaternary full-glacial periods (Stokes et al. 2006, 2009; Niessen et al. 2010; Batchelor et al. 2013). The Late Wisconsinan ice stream in M'Clure Strait is interpreted to have extended to the shelf break between 21–16 ka before undergoing rapid retreat (Stokes et al. 2009). Low rates of postglacial sedimentation have led to the preservation of an unusual assemblage of cross-cutting glacigenic landforms on the seafloor of outermost M'Clure Strait (Fig. 1). Fig. 1. ( a ) Swath bathymetry of the outer shelf of M'Clure Strait, Arctic Canada, superimposed on IBCAO v. 3.0 bathymetry (5 m contours). Multibeam acquisition system Kongsberg EM302. Frequency 30 kHz. Grid-cell size 10 m. Dashed line D indicates that the linear ridge-and-groove structures are probably continuous either side of the data gap. ( b ) Location of the study area (red box; map from IBCAO v. 3.0). MS, M'Clure Strait. ( c ) Schematic diagram showing the interpreted distribution of submarine landforms on the seafloor of M'Clure Strait which is described in the text. The probable direction of former ice flow is shown by a black arrow. The outer-shelf of M'Clure Strait contains several sets of landforms: linear ridge-and-groove structures, sinuous ridges, a wide trough-parallel ridge and three types of linear to curvilinear depressions. Multibeam imagery of the landforms is shown in Figure 1, together with a map of their distribution. Linear ridge-and-groove structures have an east–west orientation, parallel …

Cryptic no more: soil macrofossils uncover Pleistocene forest microrefugia within a periglacial desert.

Despite their critical importance for understanding the local effects of global climate change on biodiversity, glacial microrefugia are not well studied because they are difficult to detect by using classical palaeoecological or population genetics approaches. We used soil macrofossil charcoal analysis to uncover the presence of cryptic glacial refugia for European beech (Fagus sylvatica) and other tree species in the Landes de Gascogne (southwestern France). Using botanical identification and direct radiocarbon dating (140 (14) C-dates) of macrofossil charcoal extracted from mineral soils, we reconstructed the glacial and postglacial history of all extant beech stands in the region (n = 11). Soil charcoal macrofossils were found in all sites, allowing the identification of up to at least 14 distinct fire events per site. There was direct evidence of the presence of beech during the last glacial period at three sites. Beech was detected during Heinrich stadial-1, one of the coldest and driest intervals of the last glacial period in Western Europe. Together with previous results on the genetic structure of the species in the region, these findings suggest that beech persisted in situ in several microrefugia through full glacial and interglacial periods up to the present day.

An Arctic seal in temperate waters: History of the ringed seal (Pusa hispida) in the Baltic Sea and its adaptation to the changing environment

The ringed seal ( Pusa hispida) is an early immigrant in the Baltic Basin and has since its arrival experienced substantial changes in the climate, salinity and productivity of the Basin. In this paper, we discuss the dispersal and distribution of the ringed seal during different stages of the Baltic Sea in relation to past and ongoing environmental changes. Subfossil ringed seal remains around the Baltic Sea and the Danish Straits were radiocarbon dated in order to map the distribution of the species in different time periods. The δ13C data were used in evaluating the changes in the marine character of the Baltic Basin. The sequence of the dates indicates a continuous presence of the species in the Baltic Basin. The earliest ringed seal finds come from the Skagerrak/Kattegat area (Denmark, Swedish west coast) and date to the full glacial period and Baltic Ice Lake. In the Baltic Basin, the species appears in the subfossil record during the Ancylus period, but the main part of the remains date to the Littorina stage. During the Littorina stage, the distribution of the species was at least periodically wider than today, covering also southern parts of the Baltic. The presence of breeding populations in southern parts of the Baltic during the Holocene Thermal Maximum (HTM) indicates that the winters were at least periodically cold enough for winter ice. The changes in the marine influence in the Baltic Basin can be seen in the seal collagen δ13C values, which serve as a proxy for qualitative changes in water mass salinity.

The physiography of High Arctic cross-shelf troughs

A comprehensive inventory of High Arctic cross-shelf troughs is compiled from International Bathymetric Chart of the Arctic Ocean (IBCAO) bathymetric data (v. 3.0). The location of 75 cross-shelf troughs is presented alongside a synthesis of their key physiographic characteristics and available glacial-geological evidence. The troughs are interpreted to have been occupied intermittently and eroded by marine-terminating ice streams that traversed the shelf during at least one, and often many Quaternary full-glacial periods. Considerable variation in cross-shelf trough physiography exists in the High Arctic; trough lengths range between 35 and 1400 km, widths from 12 to 260 km, and maximum depths from 200 to 1000 m. The longest cross-shelf troughs extend through inter-island channels on the Beaufort Sea, Queen Elizabeth Islands and Barents–Kara Sea margins. The gradient of the upper-slope beyond High Arctic glacial troughs, which ranges between 0.3° and 13°, is shown to have a negative relationship with palaeo-ice stream drainage basin area and trough length. Glacial-sedimentary depocentres or trough-mouth fans (TMFs) are inferred on the basis of bathymetric and, where available, seismic evidence, to exist beyond the majority of High Arctic cross-shelf troughs. Evidence of shelf progradation or TMF development is absent from the slope beyond several High Arctic troughs, probably as a result of limited sediment supply to the margin and/or sediment by-passing of the upper-slope. On the South Greenland continental margin, it is likely that steep slopes prevented the development of significant glacial-sedimentary depocentres beyond cross-shelf troughs or that glacigenic debris has been removed from the upper-slope by submarine slope failure.

Movement of deep‐sea coral populations on climatic timescales

During the past 40,000 years, global climate has moved into and out of a full glacial period, with the deglaciation marked by several millennial‐scale rapid climate change events. Here we investigate the ecological response of deep‐sea coral communities to both glaciation and these rapid climate change events. We find that the deep‐sea coral populations of Desmophyllum dianthus in both the North Atlantic and the Tasmanian seamounts expand at times of rapid climate change. However, during the more stable Last Glacial Maximum, the coral population globally retreats to a more restricted depth range. Holocene populations show regional patterns that provide some insight into what causes these dramatic changes in population structure. The most important factors are likely responses to climatically driven changes in productivity, [O2] and [CO32–].

Resolution of Respect: Professor Paul Schultz Martin 1928–2010

Resolution of Respect: Professor Paul Schultz Martin 1928–2010

Palaeoenvironmental studies in NW Iberia (Cantabrian range): Vegetation history and synthetic approach of the last deglaciation phases in the western Mediterranean

At the north-western limit of the Mediterranean basin, in the Mediterranean–Oceanic transition zone, the multidisciplinary study of two palaeolakes: Villaseca and La Mata (Province of Leon), provides data on the last deglaciation. The juxtaglacial lakes were formed during a deglaciation phase of the last cold stage (Weichselian/Würm) estimated, from the regional and Pyrenean chronological data, between circa 48 ka and 32 ka (ka: 1000 years ago). Their drainage occurred circa 17 ka and 15 ka respectively, during the definitive glacial retreat phases. These results provide evidence for a glacial maximum extension preceding the global Last Glacial Maximum (LGM) and an early deglaciation. Comparisons with the Pyrenean data show that in the most important glacial basins of the Pyrenean–Cantabrian range, glaciers were still present at middle elevation circa 18–20 ka. The final deglaciation did not happen until around 16 ka. During the period 48–13.3 ka, along the Pyrenean–Cantabrian range, three stages can be distinguished in the deglacial processes. Between circa 48 and 32 ka, the deglacial retreats were contemporaneous with D–O events 12 to 6. Between circa 32 ka and 18 ka, major sedimentary modifications were rare. Two of them are synchronous with D–O 4 and 3. A glacial readvance also occurred during this period along the Pyrenean–Cantabrian range. Between 18 and 17 ka, major sedimentary changes and an increase in the δ 18O records of the NGRIP ice-core record are synchronous. Between 15 and 13.3 ka, glacial retreats and sedimentary changes are synchronous with the climatic improvement observed from the end of the Oldest Dryas to the end of the Bölling–Alleröd period. These correspondencies suggest relationships between the deglacial processes in the western Mediterranean and the palaeoenvironmental events in the North Atlantic region during the last Glacial–Interglacial transition. During the Full Glacial period, the pollen data indicates dominant steppic environments. The Oldest Dryas was not a constant cooling phase and from around 15.5 ka, the pollen data indicates a slight warming. During the Holocene, until circa 2040 cal BP, mixed oak forests developed and pine was a prominent component of the Cantabrian landscape. Then the forests were destroyed due to mining, agriculture and fire, and this favoured the extension of heathland.