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The Optically Stimulated Luminescence (OSL) age database of Finland was established, and it includes all of the published OSL age results from different sediment sequences in Finland. The OSL database includes ~180 published OSL ages ranging from 235,000 years to 300 years; that is, from the Middle Saalian interstadial to the present. Two statistical clustering methods, K-means and model-based clustering with the package mclust, were used to analyze the internal structure of the assembled OSL data. The results of these analyses were also compared to the established Northwest European (Fennoscandian) chronostratigraphical stages. When the data were analyzed by the K-means method, the “right” number of clusters (K) was seven. The model-based clustering method (K = five) created bigger clusters for the youngest and the oldest ages compared to the K-means clusters. Both methods show that the ages followed the increasing trend from the youngest to the oldest, and the standard error of ages was constantly increasing except in the age group 70–115 ka, where the standard errors were exceptionally high. Seven clusters obtained from the age data corresponded relatively well with the number of stratigraphically established interglacials and interstadials in the late Middle and Late Pleistocene in Fennoscandia. The exceptionally large standard error of ages in the Early Weichselian age group 70–115 ka might result from mixing of heterogeneous and poorly or partly bleached mineral material from both Eemian and Early Weichselian sediment layers. The OSL-dated Middle Saalian interstadial sediments in the data support a strong stadial and interstadial variation also before the Late Pleistocene.

The marine isotope stage (MIS) 5a to 4 transition (∼74 ka) was associated with rapid ice sheet expansion, declining moisture availability globally, and significant upheaval of terrestrial ecosystems across the northern hemisphere. Here, we present precisely dated speleothem trace element records spanning ∼90 to 70 ka from Dim Cave (Southern Türkiye) which provide crucial information regarding the climate response to this transition from the Eastern Mediterranean region. Trace element variability recorded in stalagmite DIM-E3 captures shifts in detrital influx, bedrock dissolution, and soil activity that collectively record two climatic signals: (1) high regional moisture availability between MIS 5c and 5b, and (2) increasingly arid conditions across the MIS 5a to MIS 4 transition. Both are contemporaneous with evidence for severe drying recorded across the Eastern Mediterranean and Middle East, as well as Asia, Europe, South America, and the North Atlantic. These results shed new light on the environmental consequences of rapid change in a climatologically sensitive region, and underscore the significance of atmospheric teleconnections in propagation of abrupt climate variability during the last glacial period. • The MIS 5-to-4 transition (∼74 ka) requires closer study in the Eastern Mediterranean. • We present precisely dated speleothem trace element records spanning ∼90 to 70 ka from Dim Cave (S. Türkiye). • Speleothem DIM-E3 records distinct changes in detrital influx, bedrock dissolution, and soil activity. • An abrupt shift to aridity is observed across the MIS 5a to MIS 4 transition. • Results underscore the consequences of rapid climate change in this hydroclimatically-sensitive region. [ABSTRACT FROM AUTHOR]

The Optically Stimulated Luminescence (OSL) age database of Finland was established, and it includes all of the published OSL age results from different sediment sequences in Finland. The OSL database includes ~180 published OSL ages ranging from 235,000 years to 300 years; that is, from the Middle Saalian interstadial to the present. Two statistical clustering methods, K-means and model-based clustering with the package mclust, were used to analyze the internal structure of the assembled OSL data. The results of these analyses were also compared to the established Northwest European (Fennoscandian) chronostratigraphical stages. When the data were analyzed by the K-means method, the "right" number of clusters (K) was seven. The model-based clustering method (K = five) created bigger clusters for the youngest and the oldest ages compared to the K-means clusters. Both methods show that the ages followed the increasing trend from the youngest to the oldest, and the standard error of ages was constantly increasing except in the age group 70-115 ka, where the standard errors were exceptionally high. Seven clusters obtained from the age data corresponded relatively well with the number of stratigraphically established interglacials and interstadials in the late Middle and Late Pleistocene in Fennoscandia. The exceptionally large standard error of ages in the Early Weichselian age group 70-115 ka might result from mixing of heterogeneous and poorly or partly bleached mineral material from both Eemian and Early Weichselian sediment layers. The OSL-dated Middle Saalian interstadial sediments in the data support a strong stadial and interstadial variation also before the Late Pleistocene. [ABSTRACT FROM AUTHOR]

The Amiens‐Renancourt 1 site recently yielded one of the most important Upper Palaeolithic human occupations of northern France by the number of flint artefacts and especially by the presence of Venus figurines. All the material comes from a single archaeological layer located in a tundra gley bracketed by loess units. A multi‐proxy study combining a detailed stratigraphy, luminescence and radiocarbon datings and high‐resolution (5 cm per sample) grain size and molluscan analyses was therefore carried out to reconstruct and date the associated environmental changes and to determine the exact context of the human occupation. The chronological frame thus established supports the correlations of the archaeology‐bearing tundra gley and of an underlying arctic brown soil with Greenland interstadials GI‐4 and GI‐3. Composition changes in the molluscan population enabled the identification of transitional and optimum phases and sub‐phases within these two pedogenetic horizons. A conceptual correlation model linking molluscan phases with millennial‐scale variations of Greenland ice‐core and Sieben Hengste speleothem climate records is proposed. The Human occupation appears contemporaneous to the end of the stadial–interstadial transition of GI‐3. Synchronous in Amiens‐Renancourt 1 and Nussloch, subsequent micro‐gleys may also result from a regional/global forcing. Such a level of detail is unprecedented in a loess sequence. [ABSTRACT FROM AUTHOR]

In this paper we focused on the micromorphology of the Late and Middle Pleistocene paleosols exposed in twelve loess-paleosol sequences sections in the central part of the East European Plain. Each studied paleosol complex known as Mesin (MIS 5), Kamenka (MIS 6 (8) - 7 (9)), and Inzhavino (MIS 8 (10) - 9 (11)) pedocomplexes (PCs) consists typically of two members, the earlier - main - phase of the soil development taking place during an interglacial, and the later one - at the subsequent interstadial time. Interglacial paleosols formation is associated with the thermal optimum of climatic macrocycles and corresponds to conditions close to modern in the territory under consideration. Interstadial paleosols formation characterizes the intervals within the glacial period, accompanied by an increase in heat and moisture. However, the heat supply of such intervals did not reach modern level in this region (Velichko and Morozova 2015). As follows from the analysis of the soil micromorphology over the studied area, the soil microstructure experienced notable changes under changing latitudinal zonality. During the interglacial periods clay coatings and Fe-Mn pedofeatures dominated the soil microfabric; in the south loess-paleosol sequences coatings are in negligible quantities, Fe-Mn pedofeatures decrease in amount, and carbonate pedofeatures appear instead. In the microfabric of the interstadial paleosols, Fe-Mn pedofeatures are abundant, but unlike interglacial paleosols, the coatings are rare. Basically, the coatings are humus-clayey in composition, but in the more southern sections coatings are absent.

We here report the results of luminescence and cosmogenic exposure dating of the Idre marginal moraine, located in the southern Scandinavian Mountains. This particular moraine is targeted because it is morphologically distinct and marks the margin of a former ice sheet. The till in the moraine contains erratics that provide strong evidence of flow from an ice sheet centred over Norway. The area immediately outside the moraine margin is an older residual soil. Luminescence ages of three samples taken from a sand lense within the moraine indicate that it formed at around 55 ka, during the early warm part of Marine Isotope Stage (MIS) 3. Median exposure ages (10Be) of ten samples from boulders embedded in the surface till indicate that about 30 ka of ice-free time have elapsed since formation of the moraine. The difference between the age of the ridge and the duration of exposure provides a measure of the time of ice-cover in the ice sheet core area. Previous research indicates that final deglaciation of the site occurred at approximately 10 ka ago, which in combination with our results implies that the area around the Idre marginal moraine was ice free for ca. 20 ka, i.e. from around 55 ka to around 35 ka. Thereafter, the area was glaciated and the marginal moraine was covered by the Late Weichselian ice sheet for around 25 ka without experiencing any significant erosion or morphological destruction. While earlier studies have already pointed towards MIS 3 ice free conditions in northern and central Sweden, this study contributes a measurement-based duration estimate for the MIS 3 interstadial.

In the context of shifting the boundary of the Quaternary down to the level of 2.6 Ma and including the Gelasian Stage in the Quaternary System, the systematization of the original and published data on the geology and paleogeography of the Late Pliocene and Early Pleistocene of Eastern Europe has been carried out. It was established that, at the boundary of the Gauss and Matuyama paleomagnetic epochs, along with the general trend toward cooling and aridization, profound landscape and climate changes occurred and rhythmic fluctuations of the climate intensified. During the period from 2.6 to 1.8 Ma, corresponding to the Gelasian (pre-Tiglian and Tiglian of Western Europe or Paleopleistocene of Eastern Europe), there appeared subarctic landscapes. In the Eopleistocene (1.8–0.78 Ma) and the Early Neopleistocene (0.78–0.42 Ma), the climate became colder, and climatic zonality repeatedly underwent a complex restructuring, gradually approaching the modern one. Glacial deposits (layers of till) occurring in Eastern Europe date back to the Paleopleistocene. Evidence indicates that there were at least three independent glaciations in the Eopleistocene (1.8–0.78 Ma) and possibly four in the Early Neopleistocene. On the basis of studies of stratotypic sections, paragenetic links were established between sediments of different age within glacial and periglacial areas, and the paleogeographic events of the Early Pleistocene of Eastern Europe were correlated with those within the Western European region. [ABSTRACT FROM AUTHOR]

Abstract The loess-paleosol sequence exposed in the Beregovoye section (southwest of the Crimean Peninsula) has been thoroughly studied. Detailed analysis of the paleosol morphology, physical properties and chemical composition, micromorphology and other characteristics made it possible to identify types of paleosols formed in the Pliocene and Pleistocene. The results obtained gave us an insight into the climate and environments of the past. According to them, the climate of the Pliocene optimum was extremely hot and wet, and the soil zonality was hardly pronounced practically over entire Central and Eastern Europe. At the final phase of the Pliocene the climate became drier, though the rainfall amount was still greater than in the Holocene. During the Early Pleistocene the soil development followed the Mediterranean type, the climate being still warm, though less humid than in the Pliocene. There are two peaks of catastrophic changes in the evolution of the climate and environments distinctly traceable in the Beregovoye section: first – corresponding to the global change recorded between the Pliocene and Pleistocene and second, falling on the initial phase of the modern (Holocene) soil formation. Highlights • There are two peaks of catastrophic changes in the evolution of the climate in the Beregovoye section. • The climate of the Pliocene optimum was extremely hot and wet. • The soil zonality was hardly pronounced over entire Central and Eastern Europe. • At the final phase of the Pliocene the climate became drier. [ABSTRACT FROM AUTHOR]

The interstadial marine deposits stratum was described in the Fildes Peninsula (King George Island) due to field and laboratory investigations during 2008–2011. The stratum fragments occur in the west and north-west parts of peninsula in following forms: sections of soft sediments, containing fossil shells, marine algae, bones of marine animals and rich marine diatom complexes in situ (11 sites); fragments of shells and bones on the surface (25 sites). According to the results of radiocarbon dating, these deposits were accumulated within the period 19–50 ky BP. Geographical and altitude settings of the sites, age characteristics, taxonomy of fossil flora and fauna, and good safety of the soft deposits stratum allow to make following conclusions: during interstadial, sea water covered significant part of King George Island up to the present altitude of 40 m a.s.l., and the King George Island glaciation had smaller size then; environmental conditions for the interstadial deposit stratum accumulation were at least not colder than today; probably, the King George island territory was covered entirely by ice masses of Last glacial maximum not earlier than 19 ky BP; during Last glacial maximum, King George Island was covered by thin, «cold», not mobile glaciers, which contribute to conservation of the soft marine interstadial deposits filled with fossil flora and fauna.

The micro- and macromorphological studies performed on the loess-soil sequences in the south of the East European Plain permitted to identify and describe the type of soil-formation processes that took part in the development of interstadial and interglacial paleosols. Four paleosol complexes are distinctly identified within the limits of the studied region: Vorona (MIS 13/15), Inzhavino (MIS 8/9 or MIS 10/11), Kamenka (MIS 6/7 or MIS 8/9), Mezin (MIS 5); besides, there are the Bryansk interstadial paleosol (MIS 3) and Rzhaksa interglacial paleosol (MIS 17), both well identifiable in the region. The results obtained are in general agreement with the earlier conclusions by Velichko et al. (2012) about a general reduction of heat and moisture supply and an increase in aridity from the earlier towards later stages of the Pleistocene. The new data revealed, however, a few differences from the earlier concept. To mention but one example, we have found that the Kamenka interglacial (MIS 7 or MIS 9) paleosols formed in environments more humid than those of the Likhvin interglacial (MIS 9 or MIS 11). [ABSTRACT FROM AUTHOR]

During recent years, many sites with sediments pre-dating the Last Glacial Maximum have been identified in formerly glaciated areas. As more and better dates are presented from these sites, the dynamic behaviour of the Scandinavian Ice Sheet is becoming increasingly clear. In this study, we revisited the site Skorgenes in western Norway. Here, sediments from two ice-free periods are found below and interbedded with glacial diamicts. We present an updated chronology for the site, based on ten new Optically Stimulated Luminescence (OSL) dates, and discuss possible correlations. The samples had poor OSL properties but still provide a substantial improvement of the existing chronology. The oldest sediments identified at Skorgenes were deposited in a proglacial subaqueous setting at some point between 21 and 42 ka. This period was followed by a glacial advance and, during the subsequent ice retreat, a delta or subaqueous fan formed at Skorgenes. OSL ages from the foreset beds indicate deposition at some point between 17 and 30 ka, implying that the ice-front retreated east of Skorgenes at least once during the Late Weichselian. A substantial ice advance followed this retreat. The youngest sediments, forming a proglacial delta succession, were deposited during the final deglaciation of the site. [ABSTRACT FROM AUTHOR]

The pre-last glacial maximum paleolake sediments at Baumkirchen, western Austria, are well known in Alpine Quaternary stratigraphy as being the type locality of the Middle to Upper Würmian transition. Their location provides a rare opportunity to investigate the vegetation history of the interior of the Alps during the last glacial cycle. A recent renewed research effort involving new drilling revealed a 250-m-thick lacustrine sequence with an older, ca. Marine Oxygen Isotope Stage (MIS) 4 phase and a younger, mid- to late MIS 3 phase. Pollen analysis reveals generally poor preservation and very low pollen concentration due to very high sedimentation rates. On the basis of pollen percentages and influx rates, six pollen zones (PZ) were assigned. PZ1 and 2 correspond to the entire ca. MIS 4 section and are characterized by only scattered vegetation representing an extremely cold and dry climate. Two stadials and two interstadials were identified in the MIS 3 section. The interstadials are characterized by well-developed open vegetation with some stands of trees, with the upper PZ6 being better developed but still forest-free. On the basis of previous radiocarbon dating, this zone (PZ6) is correlated to Greenland Interstadial (GI) 7 and the lower interstadial (PZ4) tentatively to GI 8. [ABSTRACT FROM AUTHOR]

The data obtained from investigation of the Middle and Late Neopleistocene lake sediments in the European Subarctic Region of Russia are reported. Chirva, Rodionovo (Scklov), Sula (Mikulino), and Byzovaya (Leningrad) sediments were subject to palynological analysis and investigation of particle size distribution and mineral composition. The spore-pollen spectra of the Chirva sediments demonstrate two climatic optima: the lower optimum is dominated by the pollen of Pinus sylvestris and broad-leaved species (up to 10%); the upper optimum is dominated by Picea sp. and Pinus sylvestris, while the pollen of Picea sect. Omorica and broad-leaved species are sporadic. The Rodionovo flora is characterized by a more xerophilous composition relative to the Chirva flora and a higher pollen content of pine, birch, wormseed plants, and wormwood. The climatic optimum of the Sula interglacial is distinguished by boreal vegetation, including spruce, birch, and birch-spruce forests with sparse broad-leaved species. The Byzovaya interstadial is marked by seven stages of changes in the vegetation: from tundra and forest-tundra communities to taiga forests with some broad-leaved species. The natural climatic sedimentation conditions in the Middle and Late Neopleistocene interglacial periods are reconstructed. The mineral composition of sediments was largely formed owing to underlying deposits. [ABSTRACT FROM AUTHOR]

The stratigraphy and sedimentology of a diamicton-stratified sand deposit have been studied in the Veskoniemi area, near Lake Inarijärvi in central Finnish Lapland. Test pit excavations were used for stratigraphical investigations. Till-covered laminar and cross-bedded sands were dated using optically stimulated luminescence (OSL). Ages range between 21.0 ± 1.5 and 22.4 ± 1.6 ka for laminated sands at upper levels and 39 ± 3 and 46 ± 3 ka for sands at deeper levels. These dating results strengthen the evidence for a Middle Weichselian interstadial in northern Finland during oxygen isotope stage 3, and can be compared with other results in eastern and southern Lapland. This is the first time that sediments from the Middle and Late Weichselian contact have been identified in Finland. These new dating results indicate that an ice-free period could have lasted from halfway through the Middle Weichselian to the beginning of the Late Weichselian about 22–25 ka ago in northern Finland.

Of the 24 Greenland interstadials in the Last Glacial-interglacial cycle (LGIC) only five are conventionally recognised in Britain. This paper aims to improve understanding of the LGIC in Britain from a site at Arclid, Cheshire. Sediments were characterised and luminescence used to establish a chronology. This found that the Chelford Sand Formation spans 77-47 ka with sand deposited initially by aeolian but later by fluvial transportation. Coleoptera and Diptera from the basal peat lens provided a reconstruction for a heather-rich heathland environment grazed by large herbivores, with summer temperatures between 13 and 18 °C, and winter temperatures between −14 and 1 °C. Flies included the earliest records of the blood-sucking horsefly Haematopota pluvialis , and the soldierfly Chloromyia formosa. The overlying Stockport Sand Formation was deposited fluvioglacially between 47-41 ka with the upper Stockport Till formed by the advance of the last British icesheet after ∼33 ka. Stenothermic beetle analysis from Arclid indicate similarities with results from other British mid LGIC sites, some of which are at or beyond the limit of radiocarbon dating and may be of a similar age to Arclid. Basal organic sediments found at Arclid along with other reassigned sites are proposed as a new Arclid Interstadial. A revised British LGIC chronostratigraphy has the Wretton, Chelford and Brimpton Interstadials and the previously suggested but not widely recognised Cassington Interstadial. The Arclid Interstadial occurred after these, but prior to the Upton Warren Interstadial complex. This closes the previous gap in interstadials between the Brimpton Interstadial and the Upton Warren Interstadial complex within the British chronostratigraphy. [Display omitted] • Arclid spans 77-33 ka and was an braided floodplain with heathland during interstadials. • Earliest records of fossil insects Haematopota pluvialis and Chloromyia Formosa found. • Arclid basal peat along with other reassigned sites are proposed as a new Arclid Interstadial. • A revised British chronostratigraphy for the Last Glacial Interglacial cycle is proposed. This is the Wretton, Chelford, Brimpton, Cassington and Arclid Interstadials then the Upton Warren Interstadial complex. [ABSTRACT FROM AUTHOR]

Well-dated paleorecords from periods prior to the Last Glacial Maximum (LGM) are important for validating models of ice sheet build-up and growth. However, owing to glacial erosion, most Late Pleistocene records lie outside of the previously glaciated region, which limits their ability to inform about the dynamics of paleo-ice sheets. Here, we evaluate new and previously published chronology data from the Missinaibi Formation, a Pleistocene-aged deposit in the Hudson Bay Lowlands (HBL), Canada, located near the geographic center of the Laurentide Ice Sheet (LIS). Available radiocarbon (AMS = 44, conventional = 36), amino acid (n = 13), uranium-thorium (U-Th, n = 14), thermoluminescence (TL, n = 15) and optically stimulated luminescence (OSL, n = 5) data suggest that an ice-free HBL may have been possible during parts of Marine Isotope Stage 7 (MIS 7; ca. 243,000 to ca. 190,000 yr BP), MIS 5 (ca. 130,000 to ca. 71,000 yr BP) and MIS 3 (ca. 29,000 to ca. 57,000). While MIS 7 and MIS 5 are well-documented interglacial periods, the development of peat, forest bed and fluvial deposits dating to MIS 3 (n = 20 radiocarbon dates; 4 TL dates, 3 OSL dates), suggests that the LIS retreated and remained beyond, or somewhere within, the boundaries of the HBL during this interstadial. Ice sheet models approximate the margin of the LIS to Southern Ontario during this time, which is 700 km south of the HBL. Therefore, if correct, our data help constrain a significantly different configuration and dynamicity for the LIS than previously modelled. We can find no chronological basis to discount the MIS 3 age assignments. However, since most data originate from radiocarbon dates lying close to the reliable limit of this geochronometer, future work on dating the Missinaibi Formation using other geochronological methods (e.g. U-Th, OSL) is necessary in order to confirm the age estimates and strengthen the boundaries of the LIS during this period. [ABSTRACT FROM AUTHOR]

Understanding past climate events relies for a large part on correlations between various proxy records. For the last glacial cycle, these are mainly marine and ice core records. However, such tele-connections are often based on weak arguments. For terrestrial data the Hengelo interstadial is a key event, discovered more than 4 decades ago. Here we review the age of this event, in particular by its 14 C dates, their calibration and comparison with other proxy records. We conclude that the Hengelo interstadial, at the type locality and a few nearby comparable sites, dates between 36,000 and 38,600 BP (uncalibrated radiocarbon age), corresponding to 42,350 and 41,380 calBP. Correlation of the Hengelo interstadial with ice-core records remains problematic. [ABSTRACT FROM AUTHOR]

High resolution of the color lightness, productivity proxies (TOC, chlorin, CaCO 3 , Ba-bio, Mo and U), and lithological description defined alternation of dark layers (DLs) and light layers in sediment core LV53-23 recovered from the central Japan Sea (west Yamato Rise) over the last 75 ka. Age model was constructed by AMS 14C data, tephrochronology, δ 18 O of planktonic foraminifera record, and the correlation of DLs with lightness of Japan Sea core MD01-2407 and with millennial interstadials recorded in the Greenland ice cores and East Asia stalagmites. Regional interstadials were also independently established and dated by vegetation amelioration of the surrounded land, inferred from the pollen results. Correlation of the DLs with millennial scale climate and sea level changes indicate that both interstadial warming and sea level fluctuations influence on its formation providing their individual features. During MIS 3, with sea level above −90 m, DL was formed mostly consistent with the Tada et al. (1999)’s hypotheses. During MIS 2 and 4, when sea level was nearly and below −90 m, sea level descending led to water column stratification, oxygen depletion in bottom water and facilitates the DLs formation. High-resolution lightness and productivity proxies defined the subtle structure of pronounced interstadials 14 and 12. [ABSTRACT FROM AUTHOR]

A cliff outcrop called Kluckow, in the Baltic Sea area, with a (glacio-) fluvial to (glacio-) lacustrine succession, provides a unique opportunity to resolve uncertainties in the timing and extent of several poorly constrained Weichselian ice advances. Based on a detailed lithofacies analysis, we selected four sampling horizons for luminescence dating to determine a depositional chronology. We measured both coarse-grain quartz and potassium-rich feldspar for age determination using optically stimulated luminescence (OSL) and post-IR infrared stimulated luminescence (pIRIR). Furthermore we addressed potential problems such as incomplete bleaching and quartz saturation effects. The resulting luminescence-chronology, supported by one radiocarbon age, illustrates a depositional time interval of the investigated sequence between ∼62 and ∼22 ka. Within this sequence a mussel-bearing fluvial sand indicate interstadial climate conditions at approximately 46 ka. The upper part of the section is composed of a 4 m thick glaciolacustrine silty clay and an overlying glaciofluvial sand; the latter yielded an OSL age of ∼22 ka. Shortly after these sequences formed, the subsequent ice advance (indicated by the overlying till sheet) reached the study area. Based on our new chronology and lithofacies analysis, we conclude that the Scandinavian Ice Sheet did not reach the study area between ∼62 and ∼22 ka. [ABSTRACT FROM AUTHOR]

In the present paper we report the most complete fossil avifauna from the southern cone of South America. The specimens here described were collected in the Paso Otero locality, at the middle stream of the Quequén Grande River, Pampean Region (Buenos Aires Province, Argentina). The fossiliferous levels belong to the La Chumbiada Member of Luján Formation (37,800 ± 2300 yr BP, late Pleistocene). The assemblage is represented by 60 specimens belonging to at least 22 taxa. The radiocarbon age indicates that Paso Otero birds represent the oldest late Pleistocene avifauna known from the South American continent and the first coming from a clear interstadial event (MIS3). Available evidence indicates similar environmental conditions during the MIS3 interstadial in the Pampean Region of Argentina and the post-Last Glacial Maximum stadials in southeastern Brazil. The absence of significant extinction events in the latest Pleistocene–early Holocene avifaunas of Brazil and Argentina suggests that the main avifaunal composition along southeastern continental lowlands may not be affected by the cyclic retraction and extension of open environments. On the contrary, the fossil record of Peru and Ecuador demonstrates that a large number of taxa, including aquatic and predatory-scavenger birds, have gone extinct along Andean environments at the Pacific coast, and late Pleistocene climatic oscillations may have played a more dramatic impact in these avian communities. [ABSTRACT FROM AUTHOR]

A palynological study was performed on a 2 m thick sediment sequence recovered from Mire Kupena (1356 m), a former lake in the Western Rhodopes Mountains (south Bulgaria) and supported by radiocarbon dating. The record extends back to ca. 30,000 cal. yrs. BP (Middle Pleniglacial) when the study area was occupied by wooded steppe composed of Pinus sp., Pinus peuce, some Betula, Juniperus, and cold-tolerant herb vegetation dominated by Artemisia and Chenopodiaceae. In addition, the almost continuous presence of deciduous Quercus, Tilia, Corylus, Abies, Picea, Fagus, Alnus, and Carpinus betulus pollen suggests interstadial conditions and this area could be recognized as a montane refugial place. A reconstruction of the interval between ca. 24,000 and 15,000 cal. yrs. BP was not possible due to an extremely low sediment accumulation rates or, more likely, a hiatus. The lateglacial landscape was dominated by mountain-herb steppe vegetation with isolated stands of Pinus, Betula and shrubland of Juniperus. The afforestation in the Early Holocene started with broad-leaved forests composed of Quercus with C. betulus, Carpinus orientalis/Ostrya, Ulmus, Tilia and Corylus and minor amounts of Pinus, Betula and Abies. In the Late Holocene (< ca. 4700 cal. yrs. BP) Fagus began to gain importance chiefly at the expense of the mixed oak forests, while after ca. 2000 cal. yrs. BP forests of Pinus sylvestris with some P. peuce quickly expanded around the mire. A comparison with other long palynological records from the mountains and lowlands of Bulgaria and in northern Greece reveals not only common trends in the vegetation development that are a reflection of the climate changes, but also site-specific features related to the location and topography of each site. [ABSTRACT FROM AUTHOR]

Abstract: A Late Pleistocene molluscan fauna sampled at Ban Praksa, near the Chao Phraya River mouth (Lower Central Plain of Bangkok, Thailand) is herein analyzed and paleoecologically characterized, revealing a shallow infralittoral, coarse/hard-bottomed environment. The comparison of the Ban Praksa association with several coeval ones recovered from Phra Pradaeng Formation seems to be evidence of a 10,000year hiatus between two separate groups of marine faunas, possibly belonging to different interstadial transgressive peaks that occurred during the long-term sea-level regression following the Last Interglacial. [Copyright &y& Elsevier]

Abstract: Core and seismic data from the Venice lagoon area, located in the foreland region between the northern Apennines and the southern Alps (northern Italy), allow a detailed investigation of the Late Pleistocene fully continental succession accumulated during the last glacial phase. These deposits consist of an aggrading alluvial plain, some tens of meters thick, which is locally incised by river channels, while both patchy and continuous peat layers complete the succession. In particular, a very continuous peat layer up to 1m thick (P1), sandwiched within alluvial plain sediments, is well recognizable in the whole lagoon area in both cores and seismic lines. 14 C datings of P1 reveal an age ranging between 22 and 24cal ka B.P., confirming its lateral continuity. All these elements suggest that P1 developed after an episode of marked moisture and large scale cut-off of terrigenous sediment, leading to the establishment of generalized paludal conditions probably during the Laugerie interstadial. As at these latitudes interstadial phases were commonly typified by enhanced arboreal vegetation cover preventing significant terrigenous supply, swamp areas characterized by peat accumulation developed. The present evidence is helpful to recognize stadial–interstadial cycles during the last glacial phase, and may integrate the current knowledge to establish a correlation between cycles recorded in fully continental deposits and those recognizable in ice cores and marine successions. [Copyright &y& Elsevier]

Abstract: The paleo-hydrography in the Japan Sea called a “mini-Ocean” was reconstructed based on the high-resolution analysis of diatom assemblages over the period of 150,000yr. The decrease of diatom fertilization in the Japan Sea, when it was isolated from surrounding seas due to the drop of sea-level during the glacial to stadial phase, resulted in dissolution and/or extremely low diatom production in the northern cores in the subarctic water-masses. The annual Td′-derived paleo-SSTs (°C) were controlled by the fluctuations of 2-kyr and 4-kyr periods at intervals of 20kyr and 40kyr over the last 160kyr BP, respectively. A 23-kyr cycle is recognized during the periods from 140ka to 100ka, according to the Wavelet analysis. After temperature and sea-level increased both at 133–128ka, 60–53ka and 15–10ka, oceanic warm-water diatom species predominated at 127–119ka and after 9calka in the interstadial phase. At 21.3–16.9ka and 12.9–9.8ka, sea-level and salinity increased as the transgression developed. At 10.0–7.0ka, the oceanic association shifted from cold-water species in the stadial period to warm-water ones in the interstadial phase. The fluctuations of Td′ derived-SSTs (°C) on century to millennial time-scales during the Holocene are well correlated with abrupt climatic events that different paleoclimatic proxies record in many regions of the Northern Hemisphere. [Copyright &y& Elsevier]

The stratigraphy and sedimentology of a diamicton-stratified sand deposit have been studied in the Veskoniemi area, near Lake Inarijärvi in central Finnish Lapland. Test pit excavations were used for stratigraphical investigations. Till-covered laminar and crossbedded sands were dated using optically stimulated luminescence (OSL). Ages range between 21.0 ± 1.5 and 22.4 ± 1.6 ka for laminated sands at upper levels and 39 ± 3 and 46 ± 3 ka for sands at deeper levels. These dating results strengthen the evidence for a Middle Weichselian interstadial in northern Finland during oxygen isotope stage 3, and can be compared with other results in eastern and southern Lapland. This is the first time that sediments from the Middle and Late Weichselian contact have been identified in Finland. These new dating results indicate that an ice-free period could have lasted from halfway through the Middle Weichselian to the beginning of the Late Weichselian about 22?25 ka ago in northern Finland. [ABSTRACT FROM AUTHOR]

Interstadial and non-glacial stadial sediments collected in boreholes from Sokli in northeastern Finland have been dated by optically stimulated luminescence on quartz and feldspar grains. The quartz OSL ages follow stratigraphic order, with one exception, and support the litho- and biostratigraphical correlation with the NW European mainland climate-stratigraphy and the marine oxygen- isotope stages. Feldspar IRSL dates generally overestimate the age, probably due to incomplete bleaching. The data show that during the last glacial cycle north-eastern Finland was not glaciated until MIS 5b, around 90 ka. Interstadial conditions occurred around ∼94 ka (MIS 5c), ∼74-80 ka (MIS 5a) and 42-54 ka (MIS 3). The OSL ages have large standard errors mainly due to small sample sizes, relatively poor luminescence characteristics and uncertainties in dose-rate determinations. [ABSTRACT FROM AUTHOR]

Since the rapid rate of global warming at the onset of the Bølling interstadial became evident, its cause has been under debate. It coincides closely in time with a strong global transgression called meltwater pulse 1a. One attempt at solution says that a meltwater pulse of Antarctic origin could cause an increase in North Atlantic Deep Water formation, and thus give rise to the Bølling interstadial. However, others have disputed that Antarctic meltwater would have that effect, and furthermore, the start of the Bølling interstadial is not even associated with an increase in North Atlantic Deep Water. A controversial hypothesis says that some Laurentian meltwater came from a jökulhlaup (sub-glacial outburst flood), but no study has yet shown unequivocally that sufficient amounts of water could be stored under the ice. Furthermore, according to all available data a melt-water pulse from the Laurentian ice would give rise to strong cooling, not warming. Nevertheless, meg-afloods appear instrumental in accumulating the Mississippi Fan, created entirely during the Quaternary period, and dramatic climate changes are characteristic of this period. This paper presents a hypothetical chain of events, building on the published literature and simple calculations, to investigate whether the order of magnitude is reasonable. The hypothesis is that a jökulhlaup from a Laurentian captured ice shelf flowed out through the Mississippi, boosted the Gulf Stream, reinvigorated the North Atlantic circulation, and as a result triggered the Bølling warm phase. [ABSTRACT FROM AUTHOR]

Abstract: This article reports the occurrence of a Middle Wisconsin interstadial, Pedregal, in the northern Venezuelan Andes, as demonstrated by high-resolution pollen analysis of a previously dated peat layer. Paleoclimatic trends are deduced mainly from changes in the abundance of tree pollen from the uppermost Andean forests. Previous calibration of this pollen with modern analogs has enabled reconstructions of prior altitudinal displacements of montane ecological belts and temperature changes. Paleotemperatures were deduced from the current lapse rate (−0.6°C/100m). After a glacier advance, represented by an underlying till, average temperatures increased to 3°C lower than modern temperatures during the Pedregal interstadial and then dropped again to approximately 7°C lower than modern. It is the oldest Quaternary paleoclimatic event reported thus far in the area. [Copyright &y& Elsevier]

High-resolution pollen records from the northern alpine foreland are used to evaluate the patterns of climate change during the period between the late Eemian Interglacial (marine oxygen isotope stage OIS 5e) about 115 ky ago and the end of the St. Germain II (OIS 5a, Dansgaard–Oeschger interstadial D/O IS21) about 75 ky ago. For the quantitative climate interpretation of the fossil pollen assemblages, we compare two different methods, a modern analogue technique and a mutual climatic range approach. The results not only reveal major climatic changes at the transition to stadials and interstadials, but also indicate short-term oscillations which are followed by an almost full return to the preceding climate conditions, and components of gradual trends resembling saw-tooth structures. Based on the pollen data, the climate reconstructions suggest that the optimum in St. Germain II (OIS 5a, D/O IS21) in winter temperatures was about 0.8 to 1.4 °C and in summer temperatures about 0.7 to 1.2 °C warmer than the optimum in St. Germain I (OIS 5c, D/O IS22 to IS24). The severe and short-time Montaigu cold event (iceberg discharge event C23) clearly divided St. Germain I into two thermal periods. Thus, St. Germain Ia (D/O IS24) preceding the Montaigu event is slightly more favourable than the following St. Germain Ic (D/O IS23). Since several climate oscillations occurred during these interstadials, they show only limited stability. With respect to the stadial periods, the results reveal a coherent pattern for all records. Winter temperatures during Melisey II (OIS 5b, C21) are about 1 to 4 °C lower than those during Melisey I (OIS 5d, C24). As regards short-term climate changes during Melisey I and Melisey II, consistent amelioration episodes may be distinguished during these intervals. [Copyright &y& Elsevier]

• The Likhvin-2018 section contains paleosols of the Late and Middle Pleistocene. • The Krutitsa interstadial paleosol at Likhvin may not correspond to MIS 5c. • The Bryansk paleosol (MIS 3) is polygenetic. • Interstadial paleosols were periodically exposed to fires. Studies of the loess-paleosol sequence of the center of the East European Plain have a long history. Previously, samples from loess-soil sections were taken for paleoreconstruction of climate and environment with low resolution, usually 1–2 samples per stratigraphic unit. This led to an unclear interpretation of the processes of soil formation and deposition of loess material. Our article discusses the LPS of the Likhvin stratotype section. High-resolution analysis was applied, which will allow us to trace in detail the history of the formation of the paleosol cover from the Middle Pleistocene to the present. A total of 245 bulk samples were taken from sections Likhvin-1/18 and Likhvin-2/18 and analyzed using laboratory analytics (the particle-size distribution, magnetic susceptibility, the loss on ignition values, total organic carbon, pH). Nine samples were taken for OSL dating and two samples for AMS dating to determine the age of the deposits. The micromorphological characteristics were described in detail for paleosols. The Salyn interglacial paleosol (MIS 5e) appeared to be comparable to the modern Retisols in its macro- and micromorphology and physical and chemical characteristics. As to the Krutitsa interstadial paleosol (identified formerly with MIS 5c in the sequence), our results suggest its belonging to MIS 5a. The modern prairie soils – Folic Cambisols – may be considered as its modern analogue. During the MIS 3, the Bryansk paleosol developed. The paleosol is polygenetic; in cooling, its main type (Cambisol) changed to Gleysol and finally became Cryosol. The paleosol described as belonging to MIS 7 displays all the characteristics of the Early Kamenka interglacial paleosol and develops the characteristics of Luvisols (Cutanic) type, its analogues being found in Latvia, Poland, and Hungary. There is a level of soil-formation above the Early Kamenka interglacial paleosol corresponding to the Romny paleosol (MIS 6) in its stratigraphic position. The latter statement is difficult to assert with confidence; it is not improbable that the level presents the Late Kamenka interstadial paleosol, also attributable to MIS 6. [ABSTRACT FROM AUTHOR]

In contrast to the detection and resolution of Late Pleistocene interstadials (Marine Isotope Stages; MIS 5c, 5a and 3) in marine and ice core-based oxygen isotope records, accurately defining palaeosea-levels for these events from sea level indicators remains a challenge. Commonly, such investigations have been undertaken in tectonically active, subduction-related settings, on emergent marginal marine-coastal successions above present sea level, given that the higher ice volumes during these Marine Isotope Stages resulted in ice-equivalent sea levels significantly below present, particularly in far-field settings. Delineation of palaeosea-levels for this period, has accordingly involved an assumption about the long-term rate of coastal uplift. Core SV#23 collected from the tectonically highly stable, remote far-field setting of southern Gulf St Vincent, southern Australia, in a present water depth of 40 m obtained a 3.89 m undisturbed sedimentary record of Late Pleistocene to Holocene age. The basal 2.39 m of the sediment record is of Late Pleistocene interstadial age, as it overlies the Last Interglacial Glanville Formation (128–118 ka; MIS 5e) and occurs beneath the Holocene St Kilda Formation. The extent of aspartic acid and glutamic acid racemization in the benthic foraminifer Elphidium macelliforme sampled at 2 cm intervals continuously from the interstadial succession in Core SV#23, confirms the relative age interpreted from lithostratigraphy. A mean amino acid racemization (AAR) age of 75 ± 13 ka indicates a correlation with MIS 5a, and highlights the utility of E. macelliforme as a species for AAR geochronology. As the foraminifers more closely define the timing of sedimentation, the interstadial succession is regarded as beyond the range of radiocarbon dating (>50 kyr), as revealed in a comparison of radiocarbon ages of fossil molluscs with AAR ages for E. macelliforme from the same depth intervals within the interstadial succession. All of the radiocarbon ages for fossil marine molluscs from the interstadial succession represent minimum ages, resulting from contamination by trace levels of modern radiocarbon. The foraminiferal faunal assemblages within the interstadial succession reveal changes of water depth at the time of deposition, pointing to millennial-scale sea level variability. In particular, the ratio of Elphidium crispum to E. macelliforme indicates several oscillations in relative sea level within a bandwidth of 26 to 24 ± 4.6 m below present sea level (BPSL). Notwithstanding the large uncertainty associated with palaeosea-level estimation based on the Elphidium ratio, the inferred relative sea level record is in accord with the sea level records of Barbados and the Red Sea, and points to Sub-Milankovitch interstadial sea level variability as noted in Greenland and Antarctic ice cores. • AAR in the foraminifer Elphidium macelliforme evaluates the reliability of radiocarbon ages close to the limit of the method. • Interstadial sea-levels for MIS 5a identified in the far-field setting of Gulf St Vincent, southern Australia. • Sea-level oscillations between 26–24 m below present sea level identified for MIS 5a in Gulf St Vincent, southern Australia. [ABSTRACT FROM AUTHOR]

The Middle to Late Pleistocene palaeoenvironmental record from the repeatedly glaciated central and eastern Fennoscandia is poorly known. The majority of the glacial and warm interval records have been interpreted to represent only the last, Weichselian, glacial cycle (119–11.7 ka). We have revised the crucial part of the existing stratigraphic documentation in central and southern Finland. Our findings show that a considerable part of the depositional record extends further back in time and is more complete than previously thought. One record may reach the Middle Pleistocene Holsteinian Interglacial (≈MIS 11), 424-374 ka ago, and a large number of records are tentatively attributed to the Middle Pleistocene Röpersdorf-Schöningen Interglacial (≈MIS 7) 243-191 ka ago. During this possible Röpersdorf-Schöningen Interglacial, the Gulf of Bothnia hosted larger alkaline and smaller dystrophic lakes surrounded by boreal pine forests in a continental climate with warmer summers and colder winters than today. The Eemian (≈MIS 5e) 131-119 ka sea coastal records show detailed evidence of the widespread intermixing of continental fresh and marine waters. During the Early Weichselian Brörup Interstadial (≈MIS 5c) 109-96 ka, central and southern Finland seem to have supported open birch forest tundra, later invaded by spruce; not boreal pine forest as earlier thought. The early birch vegetation faced a tundra phase which may be the Montaigu cooling event c. 103 ka ago. The revised palaeoenvironmental interpretation shows that the development during the three discussed warmer intervals is well in line with the central European vegetational development. Our palaeoenvironmental interpretations concerning Röpersdorf-Schöningen and Brörup warm intervals are preliminary and will need further investigations. No indisputable Middle Weichselian (≈MIS 3, 57-29 ka) sedimentary record seems to have been recorded in the studied area. • Eastern Fennoscandian glacial depositional record extend to Middle Pleistocene. • Glacial sequence stratigraphy reveal glaciofluvial reworking of interglacial organics. • Reworked Holsteinian and Röpersdorf-Schöningen? interglacial records in Finland. • Continental boreal forests in Finland during Röpersdorf-Schöningen? interglacial. • Open tundra birch forests widespread in Fennoscandia during Brörup interstadial. [ABSTRACT FROM AUTHOR]

Here we present phosphate oxygen isotope (δ 18O PO4) data from horse (Equus sp.) tooth enamel (bioapatite) from early Eemian and early Weichselian find levels at the archaeological site of Neumark-Nord 2, Germany. Based on the relationship between δ 18O PO4 of bioapatite, body water, local precipitation and air temperature, these data are used to reconstruct palaeoclimatic conditions contemporary to the different phases of Neanderthal activity at the site. Bulk enamel samples representing one year of growth were taken from horse teeth from early Eemian (NN2/2b [∼121 ± 5 ka], and NN2/1c) and early Weichselian (NN2/0; ∼93 ± 7 ka) find levels, and δ 18O PO4 values were then utilised to calculate δ 18O of local environmental water and mean annual air temperatures (MATs) during these phases of MIS5. Results indicate that during the early Eemian MAT was ∼9 °C, with some evidence of variability through time. Although ∼3 °C lower, the calculated early Weichselian MAT exceeds that indicated by other local and regional climate proxy datasets, suggesting that Neanderthal activity may have coincided with more ameliorate phases of the early Weichselian in this area. • Equus sp. enamel was sampled from Neumark-Nord 2 (find levels NN2/2b, 2/1c, 2/0). • δ 18O PO4 data were generated in order to estimate mean annual air temperature (MAT). • Early Eemian (∼121 ± 5 ka) MAT estimates are ∼9 °C, correlating with other proxies. • Early Weichselian (∼93 ± 7 ka) MAT was ∼6 °C, elevated compared to other proxies. • Implications for archaeology and Neanderthal-environmental interactions are explored. [ABSTRACT FROM AUTHOR]