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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.

Latérale au bassin intra-vosgien de Saint-Dié, la vallée de la Fave a enregistré une séquence sédimentaire continue depuis plus de 53 ka. Le matériel de la nappe grossière inférieure résulte d’apports torrentiels attribués à un épisode de fonte de névés et de masses de glace accumulés pendant le stade MIS 4 sur les reliefs au sud de la vallée. La nappe alluviale supérieure, à dominante silteuse, indique une sédimentation lente sans épisode torrentiel et l’absence d’accumulation significative de névés ou de glace sur le bassin versant pendant le Dernier Maximum Glaciaire et le Tardiglaciaire. Elle inclut une unité basale stratifiée et discontinue à échardes volcaniques, à matière organique datée à plus de 53 ka et de contenu pollinique à Betula/Pinus suivis d’espèces de steppe froide. L’Interstade local est dans la position palynostratigraphique de l’Interstade de Goulotte de la séquence de la Grande Pile, au début du MIS 3. Cet âge est compatible avec celui du tephra de Saint-Germain. Ces données sur la marge nord des Vosges centrales confirment le modèle d’histoire glaciaire mis en évidence dans les Vosges du sud, avec un maximum d’enneigement précoce au début du Würmien moyen (MIS 4) et une extension glaciaire plus restreinte sous climat froid et sec pendant le Würmien supérieur (MIS 2). A continuous sedimentary sequence has been deposited for more than 53 ka in the Fave River Valley, laterally to the intra-Vosgian basin of St-Dié. The coarse material of the lower alluvial sheet of the sequence is the result of torrential flows from melting neves and ice masses accumulated during MIS 4 on the highlands at the South of the valley. The upper alluvial silty sheet records a slow deposition of fine sediments without interstratified torrential beds. There was no significant accumulation of neves or ice on the southern watershed of the Fave River during the LGM and Late Glacial. The upper sheet of the sequence contains a stratified and discontinuous peaty basal unit dated to more than 53 ka and containing volcanic glass shards and interstadial Betula/Pinus pollen followed by stadial cold steppic species. The local interstadial is correlated to the Goulotte episode of the pollen sequence of Grande Pile, at the beginning of MIS 3. The age is compatible with the St-Germain tephra. These data from the northern edge of the central Vosges Mountains provide further support for the glacial model established in southern Vosges, with early heavy snowfalls during the beginning of the Middle Würmian (MIS 4) and smaller extent of the glaciers with dryer and colder climatic conditions during late Würmian (MIS 2).

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. Refereed/Peer-reviewed

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 C-14 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. (C) 2015 Elsevier B.V. All rights reserved.

Since its discovery in Greenland ice cores, the millennial scale climatic variability of the last glacial period has been increasingly documented at all latitudes with studies focusing mainly on Marine Isotopic Stage 3 (MIS 3; 28–60 thousand of years before present, hereafter ka) and characterized by short Dansgaard-Oeschger (DO) events. Recent and new results obtained on the EPICA and NorthGRIP ice cores now precisely describe the rapid variations of Antarctic and Greenland temperature during MIS 5 (73.5–123 ka), a time period corresponding to relatively high sea level. The results display a succession of long DO events enabling us to highlight a sub-millennial scale climatic variability depicted by i) short-lived and abrupt warming events preceding some Greenland InterStadial (GIS) (precursor-type events) and ii) abrupt warming events at the end of some GIS (rebound-type events). The occurrence of these secondary events is suggested to be driven by the Northern Hemisphere summertime insolation at 65° N together with the internal forcing of ice sheets. Thanks to a recent NorthGRIP-EPICA Dronning Maud Land (EDML) common timescale over MIS 5, the bipolar sequence of climatic events can be established at millennial to sub-millennial timescale. This provides evidence that a linear relationship is not satisfactory in explaining the link between Antarctic warming amplitudes and the duration of their concurrent Greenland Stadial (GS) for the entire glacial period. The conceptual model for a thermal bipolar seesaw permits a reconstruction of the Antarctic response to the northern millennial and sub-millennial scale variability over MIS 5. However, we show that when ice sheets are extensive, Antarctica does not necessarily warm during the whole GS as the thermal bipolar seesaw model would predict.

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.

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 10,000. year 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. © 2011 Elsevier Ltd.

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 1 m thick (P1), sandwiched within alluvial plain sediments, is well recognizable in the whole lagoon area in both cores and seismic lines. C-14 datings of P1 reveal an age ranging between 22 and 24 cal 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. (C) 2011 Elsevier B.V. All rights reserved.

This paper discusses the dating of stratigraphically important Quaternary sequences from a site near Fenit, Co. Kerry, which have been the subject of debate since they were first described by Mitchell in 1970. The overall stratigraphy of the Quaternary deposits have been investigated and detailed analyses of the organic material carried out. Pollen from biogenic sediments have been analysed and samples of peat dated using the uranium-thorium disequilibrium method. The pollen assemblages match no others previously recorded in Ireland and appear to represent a cool temperate phase following the last interglacial. The uranium-thorium dates of between 114000 and 123000 yr BP indicate that the deposit dates from Oxygen Isotope Stage 5, possibly post-dating the last temperate stage (the Eemian Stage interglacial; Oxygen Isotope Substage 5e). The dating of this deposit and the realisation that it is not penultimate temperate stage (Gortian) in age invalidates much recent speculation on the age of the Gortian interglacial.

International audience; The oxygen-isotope records from Greenland ice cores show a very strong, reproducible pattern of alternation between warm Greenland Interstadials (GI) and cold Greenland Stadials (GS) at millennial-scale during the last glacial period. Here we summarise what is known about this variability from ice core records. The typical cycle has a sawtooth pattern, with a very rapid warming event (occurring in a few decades), a slow cooling trend, and then a final fast cooling. 25 such events have been numbered in the last glacial. The recent GICC05 age scale provides the best available age scale that can be directly applied to this stratigraphy, and we summarise the timing of the warming events, and the length and strength of each event. The Greenland stratigraphy can be transferred to other records if we make assumptions about the contemporaneous nature of rapid events in different archives. Other parameters, such as the snow accumulation rate, and the concentration of terrestrial dust and sea salt recorded in the Greenland cores, also show a strong contrasting pattern between GI and GS. Methane concentrations are generally high during GI and lower during GS, with the increase from GS to GI occurring within a century. Antarctic ice cores show a different pattern: each GI has an Antarctic counterpart, but Antarctica appears to warm while Greenland is in a GS, and cool during GI. These changes are consistent with a mechanism involving ocean heat transport, but the rapid nature of warmings poses a challenge for modellers, while the rapid methane changes pose questions about the pattern of land biosphere emissions during the glacial that are also relevant for understanding glacial-interglacial methane variability.

Recent work suggests an emerging new paradigm for the Scandinavian ice sheet (SIS); one of a dynamically fluctuating ice sheet. This doctoral research project explicitly examines the history and dynamics of the SIS at four sites within Sweden and Norway, and provides results covering different time periods of glacial history. Two relatively new dating techniques are used to constrain the ice sheet history: the optically stimulated luminescence (OSL) dating technique and the terrestrial cosmogenic nuclide (TCN) exposure dating technique. OSL dating of interstadial sediments in central Sweden and central Norway indicate ice-free conditions during times when it was previously inferred the sites were occupied by the SIS. Specifically, the SIS was absent or restricted to the mountains for at least part of Marine Isotope Stage 3 around 52 to 36 kyr ago. Inland portions of Norway were ice-free during part of the Last Glacial Maximum around 25 to 20 kyr ago. Consistent TCN exposure ages of boulders from the Vimmerby moraine in southern Sweden, and their compatibility with previous estimates for the timing of deglaciation based on radiocarbon dating and varve chronology, indicate that the southern margin of the SIS was at the Vimmerby moraine ~14 kyr ago. In central Sweden, consistent TCN ages for boulders on the summit of Mt. Åreskutan and for the earlier deglaciated highest elevation moraine related to the SIS in Sweden agree with previous estimates for the timing of deglaciation around 10 ka ago. These results indicate rapid decay of the SIS during deglaciation. Unusually old radiocarbon ages of tree remains previously studied from Mt. Åreskutan are rejected on the basis of incompatibility with consistent TCN ages for deglaciation, and incompatibility with established paleoecological and paleoglaciological reconstructions. Altogether this research conducted in different areas, covering different time periods, and using comparative geochronological methods demonstrates that the SIS was highly dynamic and sensitive to environmental change. At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Submitted. Paper 4: Manuscript.

7 p., [EN] 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 (K0.6 8C/100 m). After a glacier advance, represented by an underlying till, average temperatures increased to 3 8C lower than modern temperatures during the Pedregal interstadial and then dropped again to approximately 7 8C lower than modern. It is the oldest Quaternary paleoclimatic event reported thus far in the area.

Between the "inner moraines" and the upperside of the Leman Lake, we observe the following elements : — two generations of "inner moraines" of as yet undetermined age, the oldest being over 241 10 ±900 B.P.; — a series of over-deepened basins now either wholly filled up with lacustrine deposits (Malville, Le Bouchage) or not (Le Bourget, Annecy, Léman), with thicknesses of several hundred meters; — a series of paraglacial or glacio-lacustrine supra-morainic deposits directly related to the déglaciation, which are disposed "en echelon" from the downstream side to the upstream side; — on single till cover to the downstream side of the Geneva basin, directly superposed to the substratum or to a wurmian ante-morainic complex; — a thick complex of superposed morainic, lacustrine and marshy deposits in which several interstadials were dated from 34550 to 23500 B.P. in the Leman basin only (Chablais, Vaud). Present chrono-stratigraphic conclusions, notably concerning the age of the maximum glacial advance, differ between the frontal area (early Wùrm) and the upstream side of the Leman basin (late Wùrm). Now, we note that : — undoubted, dated interstadial deposits only occur in the Leman basin, far upstream from the "inner moraines"; — between the "inner moraines" and the Leman basin, there is only one single till cover as well as déglaciation deposits, without any evidence of interstadial formations or of true glacial stops. Therefore, in all likelihood, the morainic deposit of the Plateau Savoyard represents one single glacial phase, predating the oldest Leman interstadials (34600 ± 2700 B. P.). One indétermination still subsists, regarding its age, in relation with both the sedimentary gaps in the glacial-interstadial series and the duration of the sedimentation process of the déglaciation and of later lacustrine deposits., Entre les moraines « internes » (Grenay, Lagnieu), et l'amont du Léman, on observe successivement : 1. Un complexe frontal de moraines «internes», d'âge encore indéterminé, dont la plus externe est toutefois antérieure à 24110 ± 900 B.P.; 2. Une couverture morainique unique à l'aval de la cuvette genevoise, accompagnée et suivie d'une série de dépôts glacio-lacustres directement liés à la déglaciation; 3. Une série de profonds surcreusement comblés par des dépôts lacustres (Malville, Basses Terres Dauphinoises) ou non (Le Bourget, Léman) sur des épaisseurs pluri-hectométriques; 4. Un épais complexe de dépôts morainiques et lacustro-palustres superposés dans lesquels plusieurs interstades sont datés entre 34550 et 23 500 ± 1200 B. P. à l'amont de Genève (Bas Chablais, pays de Vaud). On en déduit que, selon toute probabilité, les moraines « internes » et celles du plateau savoyard sont antérieures à l'interstade lémanique le plus ancien (34550 ± 1200 B.P.), que les dépôts morainiques et glacio-lacustres savoyards correspondent à une seule avancée glaciaire suivie de sa déglaciation et que le glacier du Rhône a oscillé dans les seules limites du Léman à la fin du Würm., Monjuvent Guy, Nicoud Gérard. Interprétation de la déglaciation rhodanienne au Würm, des moraines « internes » à la cuvette lémanique. In: Bulletin de l'Association française pour l'étude du quaternaire, vol. 25, n°2-3, 1988. pp. 129-140.

Es wird der Versuch unternommen, auf der Grundlage von Geländebeobachtungen und Literaturangaben eine Karte der mutmaßlichen Lößverbreitung in Oberitalien zu entwerfen. Dann werden fünf Interstadialböden beschrieben. Im Dora Ripária-Gebiet westlich Turin liegen zwei Würmlösse über dem letztinterglazialen, solifluidal umgelagerten Plastosol. Der untere ist zu einer Braunerde-Parabraunerde, der obere zu einer extrem sauren Parabraunerde verwittert. Auch der Löß auf den Rißmoränen des Dora Báltea-Gletschers gehört zwei Würmphasen an. Der darauf entstandene interstadiale und rezente Boden sind beides extreme Pseudogleye. Der fossile Boden ist reich an ehemaligen Frostspalten. Am Tessin konnte auf den Deckenschottern Riß- und Würmlöß gefunden werden. Der extrem pseudovergleyte Rißlöß ist in noch weit höherem Maße als der zu einer mäßig pseudovergleyten Braunerde verwitterte basale Würmlöß von einem Gitterwerk ehemaliger Frostspalten durchsetzt. Aus dem westlichen Gardasee-Gebiet werden zwei Solifluktionslösse über Rißmoräne beschrieben, von denen der untere zu einer Parabraunerde, der obere zu einer Parabraunerde-Braunerde verwitterte, östlich des Garda-sees wurde eine interstadiale Schwarzerdebildung angetroffen, die später zusammengeschwemmt und von Moränen überlagert wurde. Abschließend werden das Bildungsklima der fossilen Böden und ihre stratigraphische Einordnung diskutiert., research

In der Arbeit werden neue Erkenntnisse über die Stratigraphie der letzten Eiszeit in Mähren mitgeteilt. Dabei stützen wir uns nicht nur auf Lößaufschlüsse, sondern auch auf zahlreiche Grabungsergebnisse in den Höhlen des Mährischen Karstes, wo es in den Höhleneingängen gelegentlich zu Verknüpfungen der typischen Lößbildungen mit den viele paläontologische und archäologische Funde enthaltenden Höhlensedimenten gekommen ist. Wenn wir daher rein stratigraphische Erkenntnisse auswerten, stützen wir uns doch in großem Maße auf die eingeschlossenen Funde. Wir kommen zu dem Schlüsse, daß die Würmeiszeit eine stark gegliederte Periode darstellt. Aus diesem Grunde geben wir die von uns bisher benützte Bezeichnung der Interstadiale durch Abkürzungen auf und ziehen die Benennung nach den typischen Lokalitäten vor. Wir bringen weitere Beweise für die Existenz des Mittelwürm-Interstadials, welches wir mit dem Namen Interstadial Podhradem bezeichnen., research

The Greenland NEEM (North Greenland Eemian Ice Drilling) operation in 2010 provided the first opportunity to combine trace-gas measurements by laser spectroscopic instruments and continuous-flow analysis along a freshly drilled ice core in a field-based setting. We present the resulting atmospheric methane (CH4) record covering the time period from 107.7 to 9.5 ka b2k (thousand years before 2000 AD). Companion discrete CH4 measurements are required to transfer the laser spectroscopic data from a relative to an absolute scale. However, even on a relative scale, the high-resolution CH4 data set significantly improves our knowledge of past atmospheric methane concentration changes. New significant sub-millennial-scale features appear during interstadials and stadials, generally associated with similar changes in water isotopic ratios of the ice, a proxy for local temperature. In addition to the midpoint of Dansgaard–Oeschger (D/O) CH4 transitions usually used for cross-dating, sharp definition of the start and end of these events brings precise depth markers (with ±20 cm uncertainty) for further cross-dating with other palaeo- or ice core records, e.g. speleothems. The method also provides an estimate of CH4 rates of change. The onsets of D/O events in the methane signal show a more rapid rate of change than their endings. The rate of CH4 increase associated with the onsets of D/O events progressively declines from 1.7 to 0.6 ppbv yr−1 in the course of marine isotope stage 3. The largest observed rate of increase takes place at the onset of D/O event #21 and reaches 2.5 ppbv yr−1.