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Studies of the Last Interglacial (ca. 129 to 116 ka BP) provide an opportunity to study the impact of high‐latitude warm temperatures on the Earth system. To build an accurate spatio‐temporal picture of climate and environmental variability during the Last Interglacial, building robust chronologies, through which the patchwork of terrestrial, marine, and ice core archives can be correlated, is paramount. In this review, we briefly evaluate the most common approaches used to date climate and environmental archives from the Last Interglacial, as well as the chronostratigraphic tools available for direct correlation between sequences, with a focus on terrestrial archives. We then present a case study on the use of pollen biostratigraphy for correlating sequences in NW Europe, highlighting its strength as a local correlation tool, and the challenges this approach presents in comparing sequences to global records of climate and environmental change. A move towards consistently dated sequences will improve our understanding of environmental responses to Last Interglacial climate variability across different elements of the global climate system and the rates at which different elements of the climate system respond to changes in global temperatures. [ABSTRACT FROM AUTHOR]

A number of 125 open-air localities from Wielkopolska documented presence of 18 species (3 carnivores, 4 proboscideans, 3 perissodactyls and 8 artiodactyls). Most of species are cold-adapted members of mammoth fauna from the Late Pleistocene, such as Ursus arctos priscus, Mammuthus primigenius, Coelodonta antiquitatis, Equus ferus, Rangifer tarandus, and Bison priscus. The few species like Ursus arctos taubachensis, Palaeoloxodon antiquus and Stephanorhinus kirchbergensis represent an older, thermophilic fauna dated to MIS 5e. The vast majority of bones are accidental finds, without a stratigraphic context. Most artiodactyls were found in alluvial sediments, in bogs or swamps, while carnivores are represented only by isolated remains. [ABSTRACT FROM AUTHOR]

Mikulinian (Eemian) marine deposits are widespread in the northern Arkhangelsk Region, Russia. Shoreface deposits have been found in exposures along the Pyoza and Vaskha rivers; however, deposits of undoubtedly tidal origin have not hitherto been recognized there. By contrast, here we show that shells of Macoma balthica (Linnaeus, 1758) (Tellinidae, Bivalvia) unearthed from the shoreface deposits show growth patterns indicating that the bivalves lived in an environment affected by tidal periodicity. The periodicity was a mixed tide with significantly diurnal inequality in the height of the low waters. In the Arkhangelsk Region, the Mikulinian hydrodynamical conditions of the tidally influenced regime are still poorly known. Because the spatial and temporal distribution of M. balthica is broad in the fossil record, its shells have a large potential for tidal interpretations, as contribution to hydrological reconstructions. [ABSTRACT FROM AUTHOR]

Understanding supra-regional climate variability such as the changes in the North Atlantic realm is important to identify the drivers of the climate system. In this study maar lake sediments from the Eifel (western Germany) were analysed with a multi-proxy approach and compared to central and western European speleothem growth phases. C org (chlorins) and the pollen assemblage were analysed from two sediment cores of the Hoher List infilled maar lake. To generate C org (chlorins) and pollen records covering the entire last 130,000 yr b2k (years before year 2000 CE), the data from this study were stacked with published data from other Eifel maar lake sediment cores (Sirocko et al., 2013, 2021, 2022). The sediment cores from Hoher List infilled maar lake were dated by marker tephra layers giving chronological anchor points and the precise dating of the sediment cores was performed by the tuning of the C org (chlorins) records to the NGRIP δ18O record (Rasmussen et al., 2014). The speleothems, whose growth phases are compared to the lake sediment proxy records, were compiled from the literature as well as speleothems from Dechencave (western Germany) dated by the 230Th/U-method in this study. The C org (chlorins) variability shows the bioproductivity in the maar lake, which is related to water temperature and corresponds to the Greenland Interstadials (GIs) in the NGRIP δ18O record indicates its dependence on supra-regional climate variations in the North Atlantic. The pollen record shows three periods of forest with temperate forest species, during the Eemian, early Marine Isotope Stage (MIS) 3, and the Holocene. Speleothem growth in four caves in central and western Europe (Dechencave, Spannagel Cave, Hölloch Cave, Villars Cave) is predominantly sensitive to cold periods with glaciers and/or permafrost conditions above the caves inhibiting speleothem growth. The forested phases and phases of high bioproductivity in the Eifel correspond well with phases of speleothem growth indicating three warm phases in central Europe during the last glacial cycle. [ABSTRACT FROM AUTHOR]

Knowledge on the Eemian (MIS 5e) fauna of Poland is based on vertebrate remains from 16 open-air localities and 8 cave sites. Considering the short period of time covered by MIS 5e, the amount of data is surprisingly large. There is still an ongoing debate on whether the age of some assemblages is Eemian, latest Saalian or even earliest Weichselian. There are faunal assemblages or stratigraphically isolated finds with some disputable evidence. The full picture of the evolution of the Eemian vertebrate fauna in the present-day territory of Poland is still far from being complete. The finds of various groups of vertebrates (fishes, amphibians, reptiles, birds and mammals) from the Eemian Interglacial of Poland are analysed in terms of their environmental preferences. A number of thermophilic species or forms which preferred temperate climate conditions are known from this period. Among them, Clethrionomys glareolus, Glis glis, Meles meles, Martes martes, Lynx lynx, Felis silvestris, Sus scrofa, Palaeoloxodon antiquus, and Stephanorhinus kirchbergensis indicate a forest environment. The presence of species that preferred more open environments (Cricetus cricetus, Mammuthus primigenius, Coelodonta antiquitatis, and Equus ferus) is also recorded for the Eemian Interglacial of Poland. Characteristic was the presence of the large broad-toothed and flat-headed Ursus arctos taubachensis, which additionally often outnumbered remains of Ursus spelaeus sensu lato in the contemporary layers. The Eemian vertebrate fauna of Poland consisted of about 150 species (representing 61 genera and 26 families), most of which were recorded earlier from other localities of this age in central and eastern Europe. [ABSTRACT FROM AUTHOR]

Global sea levels during the last interglacial (LIG), 129,000–116,000 years ago, may have reached as much as 5–10 m higher than present. However, the elevation of the LIG highstand varies locally due to tectonics, subsidence, steric effects, and glacial isostatic adjustment (GIA). The variability brought upon by GIA can be used to constrain the past distribution of ice sheets including the source of higher sea levels during the LIG. In spite of its importance for fingerprinting the source of additional meltwater at the LIG, little is known about the elevation of LIG sea levels across Antarctica. In this study we review the geologic constraints on the elevation of the LIG highstand across Antarctica. We find that although several Late Pleistocene sea-level constraints are available across the continent very few of them provide definitive LIG ages. Arguably the most probable LIG sea-level indicators come from East Antarctica but most of them have age constraints approaching the limits of radiocarbon dating (>∼45 ka) with many likely dating to Marine Isotope Stage 3, not the LIG. For West Antarctica, Late Pleistocene sea level constraints are confined to a few poorly or completely undated possible examples from the Antarctic Peninsula. Our review suggests that much more work is needed on constraining the elevation of the LIG highstand across Antarctica. • We compile available Late Pleistocene constraints on past sea levels. • More data exists for East Antarctica than West Antarctica. • Uncertainty remains on whether these constraints are MIS3 or MIS5e in age. [ABSTRACT FROM AUTHOR]

The aim of the present study was to estimate the range of climate variability in Central Poland during the Eemian Interglacial (MIS 5e). High resolution pollen records are available for all seven RPAZs typical of this interglacial in Central Europe. These pollen records were used to estimate total annual precipitation and mean annual temperature, as well as the mean temperatures of the warmest and the coldest months based on the plant indicator method and the modern analogue technique. The reconstructions indicate that the combination of these two methods provides a much clearer insight into the climate changes of the Eemian optimum. The results confirmed no drastic drop in temperature in the Middle Eemian, with high total precipitation in the hazel phase, and that this was followed by a decrease in temperature in the Late Eemian (fir-spruce and pine phases). A drop in precipitation occurred during the youngest part of the Carpinus phase, while coincided with a marked lowering of the water level in lakes and their transformation into peatbogs. The last part of the Eemian is characterized by decreasing temperature, particularly during the coldest month, rising water levels due to a combination of lower evaporation and higher air humidity, and a transition to glacial conditions. Principal Component Analysis found all investigated sites to follow the same pattern of changes. Mean winter temperature, annual temperature and precipitation were found to have a strong positive correlation with the occurrence of thermophilus temperate broadleaved trees (hazel, linden, and ash) typical for the mid-Eemian optimum. These three factors also have a negative correlation with the presence of cold tolerant boreal trees (birch and pine) and open land taxa characteristic of the beginning and end of the interglacial. Mean July temperature was found to be positively correlated with the occurrence of temperate broadleaved trees (oak, ash and elm) typical for early stages of the Eemian and negatively with that of coniferous trees (fir and spruce) characteristic for later stages of the interglacial. [ABSTRACT FROM AUTHOR]

For the palaeo-ecological development and interpretation of the macrofauna (Bivalvia and Gastropoda) of the Eemian Sea in the southwestern Baltic Sea region (NE Germany), up to date studies and summarising assessments are largely missing. With the main goal of revising the Eemian marine fauna, the authors have undertaken numerous new samplings in recent years. This study begins by focusing on the Warnow Bay in today's Warnow valley near Rostock. In addition to examining older data from the literature, the sandpit at Schwaan and drillings of the State Geological Survey from Boitin, Reez and Rostock were studied. Parallel to this, was also undertaken pollen analyses. Despite hundreds of drillings from the region of the former Warnow Bay, evidence of the marine Eemian was relatively rare. Apparently the sandy sediments were reworked and redistributed by glaciotectonic, glaciofluvial and fluvial processes during the Weichselian glaciation. There is as yet no definite proof of autochthonous marine sediments. They are predominantly shallow-marine sands several meters thick which are found mostly at a depth of about 30–20 m b.s.l. but more rarely also relatively close to the surface in opencast mining or cliff sections. The sands are rich in marine mollusc fauna of which 29 species have been identified so far and which also include Lusitanian specimens such as Acanthocardia paucicostata , Lucinella divaricata or Polititapes senescens. Account was also taken of accompanying marine fauna such as barnacles and echinoderms. In addition, the sediments contain fresh water molluscs also including the interglacial indicator species Belgrandia germanica. [ABSTRACT FROM AUTHOR]

The Lithuanian onshore section of the south-eastern Baltic Sea region, or the so-called Lithuanian Maritime Region (LMR) – a belt several tens of kilometres wide along the Baltic Sea coast – is characterised by a complicated Quaternary structure and many of unsolved problems related to stratigraphy and palaeogeography. The inter-till lacustrine sediments widespread in the middle part of the Pleistocene thickness play a key role in solving the mentioned problems. The primary inter-till sediments were attributed, as a single lithostratigraphic unit, to the late Saalian Glaciation (MIS 6, Pamarys Sub-Formation; according to the Lithuanian Quaternary Stratigraphic Scheme). Subsequent detailed investigations show that the investigated inter-till succession represents a more complicated sediment complex formed over a wide time interval from the Saalian ice sheet decay at the very end of MIS 6 to the beginning of severe climate cooling during MIS 4. This standpoint is confirmed by the results of a few series of OSL and IR-OSL datings of inter-till sediments, as well as by data of pollen and diatom analysis. The more detailed stratigraphic subdivision of the inter-till sedimentary complex offers a new significant insight into the regional stratigraphic scheme of the Quaternary. As a result of the mentioned investigations, a new original reconstruction of the palaeogeographic situation in the LMR during the MIS 6 – MIS 3 time span was carried out. The lowermost part of the investigated inter-till sediments, attributed to MIS 6, could be correlated with the third MIS 6 warming in Northern Eurasia about 155 ka ago. The reconstruction of the palaeoenvironmental changes starting from MIS 6 and lasting to MIS 3 shows that the Eemian Sea MIS 5e in age was absent in the LMR, while part of the south-eastern Baltic Sea region was covered by a continental ice sheet during MIS 4 and, possibly, the very beginning of MIS 3. [ABSTRACT FROM AUTHOR]

During the Last Interglacial, approximately 129 to 116 ka (thousand years ago), the Arctic summer climate was warmer than the present, and the Greenland Ice Sheet retreated to a smaller extent than its current state. Previous model‐derived and geological reconstruction estimates of the sea‐level contribution of the Greenland Ice Sheet during the Last Interglacial vary widely. Here, we conduct a transient climate simulation from 127 to 119 ka using the Community Earth System Model (CESM2), which includes a dynamic ice sheet component (the Community Ice Sheet Model, CISM2) that is interactively coupled to the atmosphere, land, ocean, and sea ice components. Vegetation distribution is updated every 500 years based on biomes simulated using a monthly climatology to force the BIOME4 equilibrium vegetation model. Results show a substantial retreat of the Greenland Ice Sheet, reaching a minimum extent at 121.9 ka, equivalent to a 3.0 m rise in sea level relative to the present day, followed by gradual regrowth. In contrast, a companion simulation employing static vegetation based on pre‐industrial conditions shows a much smaller ice‐sheet retreat, highlighting the importance of the changes in high‐latitude vegetation distribution for amplifying the ice‐sheet response. Plain Language Summary: Arctic summer climates during the Last Interglacial period (approximately 129‐116 thousand years ago) were warmer than the present, and part of the Greenland Ice Sheet likely melted, contributing substantially to global sea‐level rise. Estimates of how much the ice sheet melted range widely. We use a coupled climate model that represents different parts of the Earth system (atmosphere, ocean, sea ice, land) with an evolving Greenland Ice Sheet model to simulate the period from 127‐119 thousand years ago. Our results show that the Greenland Ice Sheet reached its minimum size 121.9 thousand years ago, losing an equivalent of 3.0 m of sea level compared to the present day. We also show that changes in Arctic vegetation distribution during the Last Interglacial have a strong influence on the climate, and therefore how much the Greenland Ice Sheet retreats. Key Points: A simulation from 127 to 119 ka with CESM2‐CISM2 reveals retreat and incipient regrowth of the Greenland Ice Sheet for the Last InterglacialThe Greenland Ice Sheet reaches a minimum extent at 121.9 ka with a contribution of 3.0 m sea‐level equivalent relative to present daySimulated forest and tundra expansion in Canada and Greenland leads to greater warming and ice loss than with a pre‐industrial land cover [ABSTRACT FROM AUTHOR]

This article deals with geomorphological, sedimentary, paleopedological, chronological (OSL and 14C) and archaeological records within a segment of the Jacaré-Guaçu River alluvial plain in southeast Brazil, aiming to evaluate climatic, hydrological and landscape transformations over the past 115 ka. The results show alternations between humid and drier climates that contribute to different drainage conditions, accounting for seven paleosurfaces and five paleosols amid sandy and gravel deposits along Late Pleistocene and Holocene. Micromorphological and OSL data characterize a humid and warm phase in the Eemian associated to the formation of a paleosol under good drainage conditions, followed between 111 ka and the end of Pleistocene by sandy deposition intercalated with the genesis of two new soils and by a sedimentary discontinuity. The lithics artifacts records of Amerindian settlements since the Pleistocene–Holocene transition contributed to the demarcation of paleosurfaces that formed concurrently with landscape and river level changes, and the density of human activities was found to vary simultaneously with environmental transformations in the area. A phase of ephemeral torrential channels under a drier climate, and predominance of grassland vegetation in the Pleistocene end (~12.4 ka) was followed by the set up of perennial meandering channels of dimensions four times greater than that of the current Jacaré-Guaçu river, formed under increase of forestal associations and rise in water table, with aggradation of up 7 m, sandy deposition and formation of two new soils in the Early Holocene; from Middle Holocene, the fluvial system experienced incision (<8.5 m), avulsion (<600 m), decrease of channel size and uneven erosion of the deposits and paleosols previous formed in the area. Such changes in the landscape contributed to the establishment of lower terraces with older (115–111 ka) deposits and paleosols linked to good drainage conditions and higher terraces with newer (12.4–8.0 ka) deposits and paleosols linked to poor drainage conditions. This pattern of connections between terrace levels, soil types and ages of deposits is different from that previously registered in the alluvial plains of southeast Brazil. [ABSTRACT FROM AUTHOR]

Rias are elongated inlets, arms of the sea, that penetrate in the continental zone. These forms are understood as sea flooded river valleys since the German researcher von Richthofen introduced the term into the scientific literature in 1886. Many authors have dealt with this rocky coast macroform, and most of them highlight their fluvial origin. Nevertheless, a detailed study of the different Galician rías shows the lack of fluvial deposits or forms inside them. This fact force to reconsider the contribution of fluvial and marine factors in shaping the coast, as well as the age of these forms. With regard to this last topic, many studies show the relevance of the falling sea level in rias formation during the last glacial period, but these approaches does not take into account that inside of rías there are Eemian interglacial dated forms and deposits. A careful revision on the rías'literature and the shaping processes and agents (i.e., lithology, joint degree, or the existing of forms and deposits) lead to the conclusion that rias are polygenic forms where the tectonic structure define its morphological pattern. The fluvial dynamics, initiated in the Cenozoic, triggered the valleys incision; and the marine processes were the main agent to shaping the actual character and form of this rock coast macroforms; therefore the fluvial contribution should be understood as a secondary process. [ABSTRACT FROM AUTHOR]

Pleistocene strata of the Wadden Sea region are mostly covered by an up to 10m thick sediment wedge deposited during the Holocene transgression. However, tidal inlets cut deep into the Holocene succession, causing Middle Pleistocene to early Holocene glacial and interglacial deposits to outcrop at the channel bottom. To investigate how the lithological properties and/or morphologies of these deposits affect the development of Holocene tidal inlets (e.g. limiting erosional processes), we analysed a series of eight cores to verify three high-resolution sub-bottom transects – and thus – to extend point-based data over a broader area. Furthermore, eight additional new cores (16 WASA cores in total), and 14 reinterpreted cores from the LBEG (Geological Survey of Lower Saxony) log database, were correlated to generate three short cross-sections at the transition from the tidal inlet (Riffgat channel) to the island of Norderney, revealing a number of new aspects for the reconstruction of the Pleistocene palaeoenvironments, i.e. the last two glacials (Saalian and Weichselian) and interglacials (Holsteinian? and Eemian). A succession of Middle Pleistocene lacustrine delta deposits, belonging either to the Holsteinian or the Dömnitz temperate stage, suggests the presence of Elsterian tunnel valleys located below the island. Furthermore, we verified the presence of an Eemian mixed tidal-flat system overlain by an Eemian sand tidal flat below the western head of Norderney which is, in contrast to suggestions from previous studies, not fully eroded in this area. Finally, we demonstrate that the Saalian moraine (Drenthe Main Till) functions as a limiting constraint in the vertical development of the Holocene/modern Riffgat channel. Our results provide a better understanding of the Quaternary stratigraphy of the central Wadden Sea as well as the influence of the subsurface geology on the architecture and evolution of tidal channels. [ABSTRACT FROM AUTHOR]

Preglacial environments in Lake Ladoga, the largest European lake, located within the limits of the Scandinavian glaciations, are very poorly investigated compared to postglacial ones. They were primarily reconstructed based on the studies of terrestrial boreholes and outcrops, often incomplete and poorly dated. Previous diatom studies established that during the Eemian marine transgression, the Ladoga basin became a part of the marine Baltic-White Sea connection. However, the environments established in Lake Ladoga after the regression of the Eemian Sea are not known. This article discusses the first Early Weichselian (MIS5, ~ 118–80 ka) diatom record in Lake Ladoga obtained within the frame of the Russian-German research project PLOT. Low concentrations and selective preservation of diatoms in the preglacial sediments point to unstable high-energy environments. The presence of marine diatoms is thought to result from reworking of marine Eemian sediments, rather than direct marine influence. We argue that post-Eemian environments in Lake Ladoga were neither marine nor glaciolacustrine, as previously suggested. The Early Weichselian diatom record formed in a shallow-water part of a lake affected by inflowing streams transporting large amounts of eroded material. No analogues of the preglacial environments can be found in the postglacial Lake Ladoga. Our record demonstrates close similarity to other Early Weichselian diatom records in the Ladoga region suggesting their formation under the same conditions. Similar trends in concentrations of diatoms, diatom fragments and other siliceous microfossils reflect changing sediment supply, hydrodynamics or reworking intensity. Their lower values ~ 118–113 and ~ 90–80 ka could reflect the Early Weichselian cooling stages, while their increase between ~ 113 and 90 ka might indicate enhanced erosion intensity and increased sediment supply corresponding to the climate amelioration. [ABSTRACT FROM AUTHOR]

Scheffers, A. and Kelletat, D., 2020. Megaboulder movement by superstorms: A geomorphological approach. Journal of Coastal Research, 36(4), 844–856. Coconut Creek (Florida), ISSN 0749-0208. A longstanding geomorphological debate exists on the capability of high-intensity hurricanes to transport megaboulders. This article considers this debate, with a focus on the Bahamas during the Eemian period when sea levels have been higher. The superstorm hypothesis implies that during a warmer interglacial period, storms of unprecedented intensity would have the ability to dislodge megaboulders, against gravity, and then transport them inland to their current place of deposition, and modelling resulted in strong storms during higher sea levels as the most probable process. In this study, geomorphological arguments are tested that consider the reconstruction of the Eemian coastal landscape, focussing on original dimensions of the boulders and the position of the Eemian cliff more accurately, not excluding tsunamis as a driving force. [ABSTRACT FROM AUTHOR]

A fragment of an ursid radius with seventeen incisions (one of them incomplete) was excavated in the 1950s in the Dziadowa Skała Cave in the Częstochowa Upland in southern Poland from a deposit with faunal remains from the Eemian (ca 130–115 kyr). This object has been cited as the earliest evidence of Neanderthal cognitive abilities in the region, but it has been never studied in detail. The artefact has now been re-examined using microscopy and X-ray computed tomography. For this study we revised the determination of the bone and studied the morphology and metric parameters of the incisions (length, width, depth and opening angle). We also used experiments, statistical analysis and an analysis of the incisions' topography to establish the techniques behind their manufacture. The obtained results show that the bone was marked using a retouched stone tool, and that the incisions were produced during a single episode by a right-handed individual using repeated unidirectional movements of the tools' cutting edge. The incisions are evidently an effect of a deliberate action, not a side-effect of some practical activity. The bear radius from Dziadowa Skała is thus yet another piece of evidence for the emergence of symbolic culture, evolved by hominins in Africa and Eurasia, and represents the oldest example of marked bone north of the Carpathian Mountains. • The study of a bear radius with a set of incisions from the Eemian. • New CT method of quantitative analysis to investigate incision micromorphology. • CT method was implemented together with microscopy and experiments. • Incisions made by the repeated unidirectional movement of a retouched stone tool. • They were manufactured by a right-handed person during a single sitting. [ABSTRACT FROM AUTHOR]

• A pronounced shift in Asian monsoon is identified during the last interglacial. • There were two monsoon phases in the latter last interglacial. • Rapid demise of the last interglacial Asian monsoon was due to the gradual decrease of summer insolation. The last interglacial contains information about how climate behaves during a warm period comparable to the current interval. However, there is no consensus on the key signatures and force of the last interglacial climate changes at present. Here we present a high-resolution stalagmite oxygen isotope record from central China, which spans from 123.3 to 116.8 ka. The stalagmite δ18O time-series bears a resemblance to changes in Northern Hemisphere summer insolation before the demise of the last interglacial, like the condition during the Holocene. Superimposed on the long-term δ18O record is a pronounced shift to more positive values at around 121.6 ka, indicating a switch of the Asian monsoon mean state into a weaker condition. This monsoon shift correlates with a decrease in the mean state of the South American Summer Monsoon, and a well-known abrupt mid-Eemian cooling event at high latitudes. These correlations indicate broad-scale features of the climate shift over the warm last interglacial. Another positive δ18O shift of up to 3.5‰ occurred at around 120 ka, representing the demise of the last interglacial Asian monsoon. By comparing the stalagmite δ18O records against changes in ice volume and summer insolation during the last interglacial and recent Holocene, respectively, we conclude that the decreasing Northern Hemisphere summer insolation dominated the rapid demise of the last interglacial in the Asian monsoon region. [ABSTRACT FROM AUTHOR]

Remains of Bubalus murrensis, a thermophile bovid, are very rare in the Pleistocene interglacial faunas of Europe. The new specimen collected from the Atlantic shoreline in the Medoc (France) extents the realm of this genus far into the West, whereas the most eastern occurrence is in Romania. The fossil fragment of a horn core most probably originates from exposed interglacial deposits that are attributed to the Holsteinian (MIS 11). The Pleistocene remains of Bubalus are reviewed. All of them represent the same species B. murrensis. Sites that are well stratified belong to the Middle Pleistocene (MIS 9 and/or 11). The Upper Rhine Basin yielded about 20 cranial fragments with an assumed Eemian age. It is, however, possible that these finds predate the Eamian, hence, there is no indisputable evidence for the occurrence of Bubalus in Europe during the Eemian. [ABSTRACT FROM AUTHOR]

Fossil marine diatom assemblages in a sediment core from the central northern Faroe slope in the Norwegian Sea were used to reconstruct palaeoceanographic changes in the surface water mixed layer from the last ~130,000 years (Marine Isotope Stage (MIS) 6/5 transition to MIS 1 (including the Eemian and Holocene interglacials) and to compare the results with previously published results on planktic foraminifera representing the subsurface conditions of the thermocline. Diatom floras from MIS 5 of the Nordic seas have rarely been studied in detail before and never the entire period from pre-Eemian to present. The composition of diatom species together with maxima in absolute abundance of diatoms, indicate two periods of warmer sea surface temperatures correlating with the Eemian and Holocene interglacials, respectively. The Eemian differs from the Holocene in that the Iceland-Faroe Front never developed, suggesting the cold East Icelandic Current (originating from the East Greenland Current) running north of Iceland was reduced or more mixed with Atlantic water than during the Holocene and that the surface temperature and salinity gradients were weaker. The northern Faroe slope was in the early Weichselian of MIS 5d–5a mainly influenced by weaker inflow of Atlantic water and stronger influence of the East Icelandic Current and by seasonal sea-ice cover. During the later part of the Weichselian (MIS 4–MIS 2) cold conditions prevailed with extensive sea-ice cover except during the warmer interstadials. The diatom floras were more sensitive to climate changes than the planktic foraminifera and indicate longer periods with warm surface conditions, and increased influence of the warm Atlantic surface water from the Faroe Current in MIS 5, suggesting a shallower and much steeper thermocline during the transitional periods compared to today. The diatoms are good indicators for Atlantic water inflow and possible convection in the Nordic seas, not merely reflecting orbital variations in insolation as previously suggested. • Diatoms record surface water changes in the SE Nordic seas during MIS 5–MIS 1 • Profound shifts in upper water column structure in relation to climate variation • Diatoms more sensitive to surface change in MIS 5 and −1 than planktic foraminifera • Diatoms respond to variations in Atlantic inflow more than to insolation changes. [ABSTRACT FROM AUTHOR]

Redox-sensitive trace metals are powerful tools for the reconstruction of modern and past redox conditions in aquatic ecosystems. The most prominent example is molybdenum (Mo), which behaves conservatively as soluble molybdate in the oxygenated ocean, but forms particle-reactive thiomolybdates at sufficiently high sulfide concentrations. Previous studies proposed that the redox behavior of tungsten (W), the geochemical twin of Mo, is also affected by sulfide, suggesting its potential as a promising new redox proxy. Here we present a comprehensive W dataset from the highly sulfidic Black Sea and the weakly sulfidic Landsort Deep (Baltic Sea), as the type localities of modern euxinic basins, that combines water column, pore water, and sediment records. A dataset from the Gotland Basin obtained following oxygenation of the formerly euxinic water column during the major Baltic inflow in 2014 is used as the hypoxic example. The even stronger adsorption of W than Mo on Mn and Fe oxides at pelagic redoxclines identified these particles as important carrier transferring W from the oxygenated surface ocean to euxinic bottom waters. This shuttling was most pronounced during the inflow event in the Gotland Basin causing substantial deposition of Mn oxides that were highly enriched in W. Compared to the oxygenated surface waters, dissolved Mo was severely depleted in the highly sulfidic water column of the Black Sea, whereas the bottom water levels of dissolved W were elevated. An additional W source derived from pore-water reflux, as indicated by the exceptionally high concentrations of W in highly sulfidic pore waters from the Landsort Deep sediments. In addition to the decoupling from Mn, the pore water W enrichments are compatible with the previously proposed greater solubility of thiotungsate species than of tungstate. Despite the absence of a substantial sedimentary accumulation of authigenic W in the sapropels of the Black Sea, the comparable patterns of S, Fe, and W in an Eemian record may suggest sorption of internally cycled (thio)tungstate onto pyrite. Unexpected W enrichments in modern and medieval sediments from the central Landsort Deep indicate a close relationship with Mn carbonate formation occurring during long-lasting bottom water hypoxia. In contrast to the highly variable Mo content, the near-background variation of W in the sapropels of euxinic basins questions the utility of W as a redox proxy in euxinic systems. However, given the strong affinity between W and the Mn/Fe cycle, this element may be a useful proxy in hypoxic systems, especially its isotopic signature. [ABSTRACT FROM AUTHOR]

Reconstructing millennial‐ to centennial‐scale climate variability for the Eemian—an interval with estimated sea surface temperatures ~0.5 °C warmer than "preindustrial"—requires records with high temporal resolution. Sapropel S5 sediments, deposited under anoxic conditions in the Eastern Mediterranean Sea, offer the rare opportunity to assess multicentennial climate variability during this time. Here we present high‐resolution S5 piston core data from the Nile delta region. Specifically, we focus on Ba/Ti, Br/Ti, and Mo/Ti, as they are proxies for paleo‐productivity, marine organic carbon, and sediment anoxia, respectively. A high correlation between our Ba/Ti values in core 64PE‐406‐E1 and well‐dated Ba records of nearby cores (LC21 and ODP967) was found. We, therefore, tuned our data to these cores obtaining an initial age model. A time‐frequency analyses indicated significant frequency content in the multicentennial band, although the frequency components drifted over time. Assuming spectral simplicity, we corrected for sedimentation rate changes on a multicentennial time scale. This novel approach grants a higher‐resolution age model. The resulting variability in sedimentation rate is similar to records of monsoon variability, indicating a possible link between sedimentation at the core location and low‐latitude monsoon variability, linked via the River Nile. Moreover, the periodicities found in the sapropel time series are similar to the frequency content of total solar irradiance and sunspot records known for the Holocene, at least at high frequencies (~50–150 years). Hence, our data suggest cyclic intrasapropel variability, at least during the deposition of sapropel S5, may be linked to solar cycles. Key Points: Mediterranean Sea sediments record multicentennial variability in productivity and anoxia (Ba/Ti, Br/Ti, and Mo/Ti) during sapropel S5We corrected our time series for changes in sedimentation rate on a multicentennial time scale, by using "spectral simplicity"Sedimentation covaries with monsoon variability during S5, while multicentennial variability may be linked to solar variability [ABSTRACT FROM AUTHOR]

Geological investigations have been carried out at the Elmshorn salt diapir prompted by concern about increased karstification activity in the overburden of adjacent salt structures Krempe-Lägerdorf and Quickborn in recent years. Although only one minor collapse sinkhole has occurred in the town of Elmshorn in recent decades, drilling has revealed hollows/caves in Zechstein rock. Seen in the light of numerous older sinkholes, this new finding documents a latent danger of collapse sinkholes. Karstification occurs in salt rocks of the salt diapir, Zechstein limestones, gypsum from both the Rotliegend and Zechstein, and possibly also in chalk from the Upper Cretaceous. Neotectonic activity is represented by lineaments in the recent morphology, as well as faults and seismites within Lateglacial to Early Holocene sediments. In contrast to adjacent salt structures, Elmshorn exhibits only a few young morphological depressions at the present earth's surface, indicating active karstification. In spite of an overall low sensitivity to karstification, a higher tendency is observed in the following areas: (1) Zechstein areas, (2) transitional zones between Zechstein and Rotliegend sediments, (3) marginal areas of predominantly sandy fillings of Pleistocene buried valleys and (4) areas at suspected faults or fault zones. The fillings of the karst holes under investigation range from the Younger Tertiary (Miocene) to the Late Holocene, with the exception of the depressions of the Lieth Quarry filled with Zechstein material that have yet to be dated. Most pre-Eemian sinkhole fillings were eroded during Elsterian and Saalian glaciations, and have only been preserved in local depressions. In accordance with studies from the neighbouring structures Krempe-Lägerdorf, Peissen and Segeberg it can be stated that Eemian karstification was especially intense - this is explained by higher temperatures during this phase and generally intensified biogeochemical activity, as well as higher ground water recharge and ground water dynamics. An increased uplift of the structure during the succeeding Saalian, due to reduced subrosion under permafrost and stronger glacial rebound during Saalian/Eemian compared to Weichselian/Holocene, may play a role. Weichselian Interstadial and Holocene organic sediments are found in numerous depression fillings. [ABSTRACT FROM AUTHOR]

Abstract Based on fossil organism remains including plant macrofossils, charcoal, pollen, and invertebrates preserved in syngenetic deposits of the Batagay permafrost sequence in the Siberian Yana Highlands, we reconstructed the environmental history during marine isotope stages (MIS) 6 to 2. Two fossil assemblages, exceptionally rich in plant remains, allowed for a detailed description of the palaeo-vegetation during two climate extremes of the Late Pleistocene, the onset of the last glacial maximum (LGM) and the last interglacial. In addition, altogether 41 assemblages were used to outline the vegetation history since the penultimate cold stage of MIS 6. Accordingly, meadow steppes analogue to modern communities of the phytosociological order Festucetalia lenensis formed the primary vegetation during the Saalian and Weichselian cold stages. Cold-resistant tundra-steppe communities (Carici rupestris-Kobresietea bellardii) as they occur above the treeline today were, in contrast to more northern locations, mostly lacking. During the last interglacial, open coniferous woodland similar to modern larch taiga was the primary vegetation at the site. Abundant charcoal indicates wildfire events during the last interglacial. Zoogenic disturbances of the local vegetation were indicated by the presence of ruderal plants, especially by abundant Urtica dioica, suggesting that the area was an interglacial refugium for large herbivores. Meadow steppes, which formed the primary vegetation during cold stages and provided potentially suitable pastures for herbivores, were a significant constituent of the plant cover in the Yana Highlands also under the full warm stage conditions of the last interglacial. Consequently, meadow steppes occurred in the Yana Highlands during the entire investigated timespan from MIS 6 to MIS 2 documenting a remarkable environmental stability. Thus, the proportion of meadow steppe vegetation merely shifted in response to the respectively prevailing climatic conditions. Their persistence indicates low precipitation and a relatively warm growing season throughout and beyond the late Pleistocene. The studied fossil record also proves that modern steppe occurrences in the Yana Highlands did not establish as late as in the Holocene but instead are relicts of a formerly continuous steppe belt extending from Central Siberia to Northeast Yakutia during the Pleistocene. The persistence of plants and invertebrates characteristic of meadow steppe vegetation in interior Yakutia throughout the late Quaternary indicates climatic continuity and documents the suitability of this region as a refugium also for other organisms of the Pleistocene mammoth steppe including the iconic large herbivores. Highlights • The vegetation history (MIS6-MIS2) from the Batagay permafrost outcrop is reported. • The study region was a northern tree refuge throughout the late Quaternary. • Modern steppes in the Yana highlands are relicts of a formerly closed steppe belt. • Species diagnostic for tundra-steppe vegetation were unexpectedly scarce. [ABSTRACT FROM AUTHOR]

Projections of future rates of mass loss from the Greenland Ice Sheet are highly uncertain because its sensitivity to warming is unclear. Geologic reconstructions of Quaternary interglacials can illustrate how the ice sheet responded during past warm periods, providing insights into ice sheet behavior and important tests for data-model comparisons. However, paleoclimate records from Greenland are limited: Early Holocene peak warmth has been quantified at only a few sites, and terrestrial sedimentary records of prior interglacials are exceptionally rare due to glacial erosion during the last glacial period. Here, we discuss findings from a lacustrine archive that records both the Holocene and the Last Interglacial (LIG) from Greenland, allowing for direct comparison between two interglacials. Sedimentary chironomid assemblages indicate peak July temperatures 4.0 to 7.0 ±C warmer than modern during the Early Holocene maximum in summer insolation. Chaoborus and chironomids in LIG sediments indicate July temperatures at least 5.5 to 8.5 ±C warmer than modern. These estimates indicate pronounced warming in northwest Greenland during both interglacials. This helps explain dramatic ice sheet thinning at Camp Century in northwest Greenland during the Early Holocene and, for the LIG, aligns with controversial estimates of Eemianwarming from ice core data retrieved in northern Greenland. Converging geologic evidence for strong LIG warming is challenging to reconcile with inferred Greenland Ice Sheet extent during the LIG, and the two appear incompatible in many models of ice sheet evolution. An increase in LIG snowfall could help resolve this problem, pointing to the need for hydroclimate reconstructions from the region. [ABSTRACT FROM AUTHOR]

Limnological reconstructions of primary productivity have demonstrated its response over Quaternary timescales to drivers such as climate change, landscape evolution and lake ontogeny. In particular, sediments from Lake Baikal, Siberia, provide a valuable uninterrupted and continuous sequence of biogenic silica (BSi) records, which document orbital and sub-orbital frequencies of regional climate change. We here extend these records via the application of stable isotope analysis of silica in diatom opal (δ 30 Si diatom ) from sediments covering the Last Interglacial cycle (Marine Isotope Stage [MIS] 5e; c. 130 to 115 ka BP) as a means to test the hypothesis that it was more productive than the Holocene. δ 30 Si diatom data for the Last Interglacial range between +1.29 and +1.78‰, with highest values between c. 127 to 124 ka BP (+1.57 to +1.78‰). Results show that diatom dissolved silicon (DSi) utilisation, was significantly higher (p = 0.001) during MIS 5e than the current interglacial, which reflects increased diatom productivity over this time (concomitant with high diatom biovolume accumulation rates [BVAR] and warmer pollen-inferred vegetation reconstructions). Diatom BVAR are used, in tandem with δ 30 Si diatom data, to model DSi supply to Lake Baikal surface waters, which shows that highest delivery was between c. 123 to 120 ka BP (reaching peak supply at c. 120 ka BP). When constrained by sedimentary mineralogical archives of catchment weathering indices (e.g. the Hydrolysis Index), data highlight the small degree of weathering intensity and therefore representation that catchment-weathering DSi sources had, over the duration of MIS 5e. Changes to DSi supply are therefore attributed to variations in within-lake conditions (e.g. turbulent mixing) over the period, where periods of both high productivity and modelled-DSi supply (e.g. strong convective mixing) account for the decreasing trend in δ 30 Si diatom compositions (after c. 124 ka BP). [ABSTRACT FROM AUTHOR]

The Eemian was the last interglacial period (~130 to 115 ka BP) to precede the current interglacial. In Eastern Mediterranean marine sediments, it is marked by a well-developed and organic-rich “sapropel” layer (S5), which is thought to reflect an intensification and northward migration of the African monsoon rain belt over orbital timescales. However, despite the importance of these sediments, very little proxy-independent stratigraphic information is available to enable rigorous correlation of these sediments across the region. This paper presents the first detailed study of visible and non-visible (cryptotephra) layers found within these sediments at three marine coring sites: ODP Site 967B (Levantine Basin), KL51 (South East of Crete) and LC21 (Southern Aegean Sea). Major element analyses of the glass component were used to distinguish four distinct tephra events of Santorini (e.g., Vourvoulos eruption) and possible Anatolian provenance occurring during the formation of S5. Interpolation of core chronologies provides provisional eruption ages for the uppermost tephra (unknown Santorini, 121.8 ± 2.9 ka) and lowermost tephra (Anatolia or Kos/Yali/Nisyros, 126.4 ± 2.9 ka). These newly characterised tephra deposits have also been set into the regional tephrostratigraphy to illustrate the potential to precisely synchronise marine proxy records with their terrestrial counterparts, and also contribute to the establishment of a more detailed volcanic history of the Eastern Mediterranean.

Abstract The article presents the early results of research of sediments from a palaeolake in the Kleszczów Graben, central Poland. A total of 190 samples were collected and then ca 10–30 samples were botanically (diatoms, pollen and woody macrofossils), zoologically (Cladocera, Mollusca and Ostracoda) and geochemically (elemental content, carbon and nitrogen isotopes) tested. The results of muliproxy analysis of the Eemian (Aleksandrów Formation) and Vistulian (Weichselian; Piaski Formation) deposits helped to reconstruct the environmental changes occurring in the studied palaeolake. Palynological diagram of individual spectra "Parchliny 2014" was divided into five zones that represent local sets of pollen zones (E3−E7; PA-1−PA-5). This diagram, although incomplete, reveals the distinct Eemian features. Lithological, Cladocera and diatom analysis supported by geochemical studies indicate the existence of at least three main stages of the lake developed in the part of the basin. The lake originated from a post-Saalian melt-out kettle hole where the deposition of peats and organic, and mineral silts of different thicknesses to 10–12 m occurred (the first stage). In the second stage, initially existed a closed fairly deep Eemian lake under relatively warm conditions. The lower part of the section records an event of water body shallowing, consisting in its eutrophication, from oligotrophic to a lake of higher trophic status. Subsequently, in a cooler climate of Early Vistulian (Weichselian), the lake became shallower, and then open, flow and better oxygenated (flow-trough). Low frequency of ostracods and the absence of molluscs indicate slightly alkaline pH in the lower part of the water body, and neutral or slightly acidic pH in its upper part. At the bottom, the dominant organisms were diatoms, whereas toward the top, phytoplankton disappears and benthic taxa become predominant. Finally, in the third stage, in Plenivistulian, it was completely covered by mineral-organic and mineral sediments. [ABSTRACT FROM AUTHOR]

Abstract The Eemian-Vistulian developmental history of the Ławy paleolake (Eastern Poland) has been studied by analysing records of micro- (pollen, Cladocera, Ostracoda), macrofossils (molluscs, mammal remains), the lithological record and radiocarbon dating from a 5.30 m sediment core. At Ławy, in the Paterebo stream valley, well-preserved mammal fossil remains accompanied by organic deposits have also been investigated. The results of the multi-proxy analyses suggest explicitly that the climate was the main driving force of the changes in terrestrial and aquatic ecosystems, and in the geomorphological processes in the catchment. However, we propose that the water level fluctuations were also an important factor in the modification of the aquatic assemblages. Pollen, cladocerans, molluscs and ostracods from Ławy indicate the existence of a small, shallow, well-vegetated paleolake during the warm Eemian climate optimum. In the final phase of the Eemian the lake was transformed into a mire. In the Early Vistulian, the variable hydrological conditions were the main driver force for the development of the study area. Finally the existence of the basin at Ławy was closely associated with periodic coexistence of limnic, telmatic and river environments. [ABSTRACT FROM AUTHOR]

Abstract The lithological and palaeobotanical research conducted in a closed-drainage depression located in the watershed zone between the Mroga and Mrożyca Rivers (Central Poland) allowed for the reconstruction of its palaeogeography in the period subsequent to the retreat of the last ice sheet (Wartanian Stage of the Odranian Glaciation). The purpose of this article is to gather and synthesise the obtained results, as well as to reconstruct the processes of development and filling in the studied depression over the last 135,000 years. The post-glacial evolution of the relief was recorded in the mineral and biogenic sediments deposited on glacial formations. The modern closed-drainage depression is a trace of a fossil extensive glacial meltout depression. The post-glacial development of the land relief within the depression involved three stages, dominated by different types of morphogenesis, i.e. the deglaciation stage during the Wartanian Stage of the Odranian Glaciation, the Eemian Interglacial-Early Vistulian aggradation stage, and the Vistulian aggradation-denudation stage. High thickness of the identified biogenic sediments suggests considerable transformations of the relief of the watershed during the two cycles of temperate climate – the Eemian Interglacial and the Holocene. The thickness of the mineral sediments suggest low dynamics of the environment during the Last Glacial Maximum (LGM), and undermine the hypotheses on the determining effect of periglacial conditions on the character of the relief of Central Poland. The obtained results constitute an inspiration and starting point for another research project concerning the reconstruction of the watersheds in Central Poland. [ABSTRACT FROM AUTHOR]

Abstract One of the longest (above 7 m thick) uninterrupted Eemian-Vistulian (Weichselian) pollen successions in Poland is known from Kubłowo (central Poland). The huge importance of this succession is manifested in the possibility of study the evolution of the lake environment under the influence of changing, from interglacial to glacial climatic conditions. The reconstruction of the environmental changes at Kubłowo and its surroundings show the short climate fluctuations and a detailed picture of the natural conditions prevailing in central Poland (central Europe) during the period from approximately 126,000 to 55,000 years BP. Based on the results of multi-proxy analysis, four lacustrine stages linked with a higher water level and three boggy stages (low water level) of evolution of the Kubłowo paleolake were observed. The pollen diagram from Kubłowo reveals a succession of eighteen local pollen assemblage zones (K1-K18 L PAZ). The K1 to K7 LPAZ zones record the interglacial succession correlated with the Eemian. The next pollen zones, K8 to K18, are linked with the Vistulian. The pollen sequence shows, between the Eemian Interglacial (MIS 5e) and the last glaciation (second stadial of the Plenivistulian (MIS 4-3), four cold intervals that are interpreted as stadial phases: Herning, Rederstall, Schalkholtz and Ebersdorf separated by three temperate intervals (interstadials): Brörup, Odderade and Oerel. In the studied sediments, 25 species of subfossil Cladocera were identified, and ten zones of fauna development were distinguished. The unique feature of this profile is the good preservation of above 100,000-year-old Cladocera remains and a high diversity of species, which are primarily littoral. The Middle and Late Eemian were periods convenient to Cladocera development due to high temperatures, high water levels, high trophy and occurrence macrophytes. A deterioration of fauna living conditions started in the Late Eemian and next took place in the Vistulian cold events. The results of isotopic and geochemical analyses of organic matter from Kubłowo have enabled the reconstruction of varying environmental conditions and the origin of organic matter. The organic carbon content (TOC) changes from 1% to 40% and is closely related to climatic conditions. During the Eemian, the amount of TOC systematically increased. The lowest values are recorded in the coldest periods during the Herning, Rederstall and Schalkholz Stadials. The C/N atomic ratio fluctuates from 13 to 34 and the highest values occur in the Brörup Interstadial. The values of δ13C change from −27.9 to −12.9‰, and δ15N values oscillate between −1.6 and +5.3‰. [ABSTRACT FROM AUTHOR]

Here we present new observations of Spiniferites alaskensis, a relatively rare species described from the Eemian of the Gulf of Alaska. We show that the species shows a gonyaulacacean tabulation: Po, 4´, 6´´, 6c,? s, 6´´´, 1p, 1´´´´. The surface is finely granulate to scabrate. The species bears characteristic processes: these are exclusively gonal, membranous, perforated and end distally in platforms with stumpy ends. We provide more detail as how this species compares to closely related species belonging to the genus Spiniferites. [ABSTRACT FROM AUTHOR]

Sea levels at the end of this century are projected to be 0.26–0.98 m higher than today. The upper end of this range, and even higher estimates, cannot be ruled out because of major uncertainties in the dynamic response of polar ice sheets to a warming climate. Here, we propose an ecological genetics approach that can provide insight into the past stability and configuration of the West Antarctic Ice Sheet (WAIS). We propose independent testing of the hypothesis that a trans-Antarctic seaway occurred at the last interglacial. Examination of the genomic signatures of bottom-dwelling marine species using the latest methods can provide an independent window into the integrity of the WAIS more than 100,000 years ago. Periods of connectivity facilitated by trans-Antarctic seaways could be revealed by dating coalescent events recorded in DNA. These methods allow alternative scenarios to be tested against a fit to genomic data. Ideal candidate taxa for this work would need to possess a circumpolar distribution, a benthic habitat, and some level of genetic structure indicated by phylogeographical investigation. The purpose of this perspective piece is to set out an ecological genetics method to help resolve when the West Antarctic Ice Shelf last collapsed. [ABSTRACT FROM AUTHOR]

Biological proxies from the Sokli Eemian (Marine Isotope Stage 5e) paleolake sequence from northeast Finland have previously shown that, unlike many postglacial records from boreal sites, the lake becomes increasingly eutrophic over time. Here, principal components (PC) were extracted from a high resolution multi-element XRF core scanning dataset to describe minerogenic input from the wider catchment (PC1), the input of S, Fe, Mn, and Ca-rich detrital material from the surrounding Sokli Carbonatite Massif (PC2), and chemical weathering (PC3). Minerogenic inputs to the lake were elevated early in the record and during two abrupt cooling events when soils and vegetation in the catchment were poor. Chemical weathering in the catchment generally increased over time, coinciding with higher air temperatures, catchment productivity, and the presence of acidic conifer species. Abiotic edaphic processes play a key role in lake ontogeny at this site stemming from the base cation- and nutrient-rich bedrock, which supports lake alkalinity and productivity. The climate history at this site, and its integrated effects on the lake system, appear to override development processes and alters its long-term trajectory. [ABSTRACT FROM PUBLISHER]

As global climate warms and sea level rises, coastal areas will be subject to more frequent extreme flooding and hurricanes. Geologic evidence for extreme coastal storms during past warm periods has the potential to provide fundamental insights into their future intensity. Recent studies argue that during the Last Interglacial (MIS 5e, ~128-116 ka) tropical and extratropical North Atlantic cyclones may have been more intense than at present, and may have produced waves larger than those observed historically. Such strong swells are inferred to have created a number of geologic features that can be observed today along the coastlines of Bermuda and the Bahamas. In this paper, we investigate the most iconic among these features: massive boulders atop a cliff in North Eleuthera, Bahamas. We combine geologic field surveys, wave models, and boulder transport equations to test the hypothesis that such boulders must have been emplaced by storms of greater-than-historical intensity. By contrast, our results suggest that with the higher relative sea level (RSL) estimated for the Bahamas during MIS 5e, boulders of this size could have been transported by waves generated by storms of historical intensity. Thus, while the megaboulders of Eleuthera cannot be used as geologic proof for past "superstorms," they do show that with rising sea levels, cliffs and coastal barriers will be subject to significantly greater erosional energy, even without changes in storm intensity. [ABSTRACT FROM AUTHOR]

Obstacles to our understanding of Neanderthal land-use patterns during the Last Interglacial (130kya-116kya, Marine Isotope Stage 5e) include not only the scarcity of sites in Europe but also a lack of knowing what the landscape may have looked like during this time. This research explores the influence of climate on Neanderthal land-use. Recently developed global climate models are capable of simulating past climate variables (e.g., precipitation and temperature), and geographic information system (GIS) tools can then be used to interpolate these data to model the niches of past organisms into paleoclimate zones. This study uses Maximum Likelihood Classification analysis in GIS to create a mosaic landscape of 22 paleoclimate zones to reconstruct what Europe may have looked like during the Last Interglacial Eemian. When overlain with the location of Last Interglacial archaeological sites, it is possible to visualize Neanderthal landscape use with respect to these climate zones. The modeled paleoclimate zones show there was a preference for site locations in Warm Temperate and Mesic climates. It also shows that Neanderthals did not commonly live near climate zone margins, preferring to stay in their “home” climate zone. The Warm Temperate and Mesic climate regime may have been preferred as a more climatically stable region, resulting in less biological stress related to thermoregulation. [ABSTRACT FROM AUTHOR]

The last interglacial climate was influenced by substantial changes in the annual insolation cycle that led to a warmer climate state with pronounced high northern latitude warming. We analyze the impact of the insolation changes 125,000 years before present using an equilibrium snapshot simulation with the EC-Earth coupled climate model at high spatial resolution. Using additional atmosphere-only simulations, we separate the direct impact from the changed insolation from the secondary contribution from changed sea surface conditions. These simulations are forced with a combination of last interglacial sea surface temperatures and sea ice conditions and pre-industrial insolation, and vice versa. The coupled simulation yields an annual mean global warming of approximately 0.5 °C compared to pre-industrial conditions. While the warming over the continents follows the annual cycle of the insolation anomalies, two regions exhibit persistent responses throughout the year: The tropical region exhibits lower temperatures and stronger monsoonal systems, while the Arctic region shows a warming of more than 2 °C in all seasons. The hybrid simulations reveal that the changed sea surface conditions dominate the response at high northern latitudes, including the North Atlantic region and Europe, while the direct insolation impact is more dominant in the tropics. [ABSTRACT FROM AUTHOR]