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An understanding of the growth and demise of ice sheets over North America is essential to inform future climate models. One poorly studied subject is the glacial dynamics during interstadial Marine Isotope Stage (MIS) 3 (57–29 ka). To better constrain the southern margin of the Laurentide Ice Sheet during this time period, we re-examined a stratigraphic sequence in southeast Manitoba, Canada, and provide robust evidence for advance and retreat of ice. Around 46.6 ± 5.1 ka (1σ error), fluvial sands were deposited under similar precipitation and significantly cooler summer temperatures than present-day. Ice then advanced south over the area, before retreating once again and a return to boreal forest and grassland conditions. The area was then covered by proglacial Lake Vita, dammed by ice to the north. Geochronology constraints indicate Lake Vita existed from ca. 44.3 ± 3.6 to 30.4 ± 2.3 ka (1σ error), although gaps in the optical and finite radiocarbon ages suggest either a lack of data or plausible temporary ice-margin advances during this time period. Ice covering most of Manitoba during MIS 3 is in line with global δ18O records, and glacially influenced sediment deposition in the Mississippi River basin. [ABSTRACT FROM AUTHOR]

Recent technological advancements in spectral imaging core-scanning techniques have proved to be a promising tool to study lake sediments at extremely high resolution. We used this novel analytical approach to scan core AU3 of the Pleistocene Auel maar, Western Germany. The resulting ultra-high-resolution RABD670 spectral index, a proxy for the lake's primary production, shows an almost complete succession of Greenland Interstadials of the NGRIP ice core chronology back to around 60,000 years. Using the ELSA-20 chronology and its anchor points to the NGRIP record as a stratigraphic basis, we were able to compare and fine-tune prominent climate signals occurring in both regions. This in-depth correlation yields strong evidence that the climates of Greenland and Central Europe were not only strongly coupled on timescales of stadials and interstadials but even on multidecadal scales, showing prominent climate cycles between 20 and 125 years. As climate changes in these regions were ultimately driven by variations in the North Atlantic meridional heat transport, their strong coupling becomes most apparent during cold and arid intervals. In contrast, longer-lasting warmer and more humid phases caused the activation of various regional feedback mechanisms (e.g., soil formation, forest growth), resulting in more complex patterns in the proxy records. [ABSTRACT FROM AUTHOR]

Archaeological deposits from Waterfall Bluff Rock Shelter (Eastern Cape) span from Marine Isotope Stage 3 (~39–29 ka) to the mid-Holocene (~8 ka), showing persistent human occupations. The site’s consistent proximity to the shoreline and stable coastline over millennia makes it key for exploring human settlement patterns. This study reports on preliminary results of identifiable fauna from Marine Isotope Stage 3 to the Early Holocene layers at Waterfall Bluff. The identified species may suggest a mosaic environment, although caution is warranted given the small sample size. Furthermore, leopard seal remains were recovered in layers dating to the Last Glacial Maximum. This is the first direct evidence of a leopard seal recovered from Pleistocene and Holocene archaeo-faunal assemblages along the South African coast. Significance: Last Glacial Maximum (LGM) sites are rare in southern Africa. Waterfall Bluff in the Eastern Cape shows that human occupation persisted there from Marine Isotope Stage 3 to the mid-Holocene. A leopard seal tooth was identified in the LGM layers, making it the first evidence of this species recovered off South Africa’s coast.

The regional impact of abrupt glacial climate variability remains poorly constrained for arid southwestern Asia, particularly winter dynamics during Marine Isotope Stage 3, due to limited paleoarchives in the Middle East. Here, we present continuous speleothem records of δ18O and δ13C with robust chronologies for southwestern and central Iran, spanning ∼50–30 ka. Stable‐isotope signals in the two stalagmites are generally uncorrelated and do not exhibit a consistent response to Greenland stadials or interstadials; however, both show a positive δ18O excursion that coincides with Heinrich event 4. We explore the potential mechanisms for intermittent coupling of speleothem δ18O across Iran through isotope‐enabled atmospheric modeling outputs, from which we utilize the spatial δ18O gradient as a proxy for wintertime westerly versus southerly jet strength. Our results suggest that during Heinrich event 4 and several Greenland stadials, stronger westerly winds enhanced Mediterranean moisture contributions to both sites and reduced aridity in southern Iran. Plain Language Summary: Stalagmites are useful archives to reconstruct the climate of the past. In order to shed light on the past climate of western Asia and the response of this region to the rapid climate changes, here we present two stalagmites from central and southwestern Iran that span 50,000 to 30,000 yrs ago. Our findings suggest that during extreme cold events, the moisture originates mostly from the west, whereas out of these extraordinarily cold periods moisture comes mostly from the south. Key Points: Continuous high‐resolution speleothem record of climatic change in southwestern and central Iran between 50 and 30 kaDecoupled responses of stable‐isotope gradients in central and southern Iran to glacial climate variability, except during Heinrich event 4Decreased impact of southerly moisture sources and reinforced westerlies during extreme cold events [ABSTRACT FROM AUTHOR]

We analyzed mineralogical characteristics, and major as well as rare earth element concentrations, from a cryptotephra layer in sediments of the infilled maar of Auel (Eifel, Germany). The results of detailed geochemical analyses of clinopyroxenes and their glassy rims from the Auel cryptotephra layer showed that they are similar to those from the thick Campanian Ignimbrite tephra occurrence in a loess section at Urluia (Romania). Both tephras show idiomorphic green clinopyroxenes and formation of distorted grains up to millimeter scale. The cryptotephra in the Auel core has a modelled age of around 39,940 yr b2k in the ELSA-20 chronology, almost identical to the latest 40Ar/39Ar dates for the Campanian Ignimbrite/Y-5 (CI/Y-5) eruption. These observations suggest that parts of the CI/Y-5 ash cloud were transported also northwestward into Central Europe, whereas the main branch of the CI/Y-5 ash plume was transported from southern Italy towards the NE, E, and SE. Based on pollen analyses, we conclude there was no direct effect on vegetation from the CI/Y-5 fallout in the Eifel area. Trees, shrubs, and grasses remained at pre-tephra-airfall levels for roughly 240 years, but changed around 39,700 yr b2k when thermophilic woody plants (e.g., Alnus and Carpinus) disappeared and Artemisia spread. This change in vegetation was well after the Laschamp geomagnetic excursion and also after the GI9 interstadial and quite probably represents the onset of the Heinrich Event 4 (H4) cold spell, when climatic conditions over the North Atlantic, and apparently also in Central Europe, deteriorated sharply. [ABSTRACT FROM AUTHOR]

Marine Isotope Stages (MIS) 4 and 3 were significant periods encompassing some 50,000 years, including at least two techno-cultural entities: the Howiesons Poort (HP) and post-HP. Exploring subsistence and environmental changes during these periods may help us understand broader aspects of behavioural and occupational patterns over MIS 4 and 3. In this paper, we report on taphonomic analyses of a sample of early HP, late HP and post-HP fauna from Klasies River main site cave 1A. We use these and other faunal data to examine the links between subsistence behaviour and the environment during the HP and post-HP. The results of our analyses indicate that percussion marks are abundant in the HP, with percussion mark frequencies more prevalent in the later HP than the early HP indicating that humans were the primary accumulators of fauna in the HP. Other taphonomic data such as fracture patterns, burning and trampling marks also suggests that human activity was more prevalent in the HP than the post-HP. In contrast, in the post-HP, the prevalence of zoogenic marks on small mammal remains, and comparisons to actualistic assemblages indicate that carnivores probably contributed significantly to the post-HP assemblage. In all the samples investigated, crania dominate skeletal-part profiles. This could be a result of taphonomic bias, or it could indicate that foraging likely occurred relatively close to the site. Analyses of carcass-part utility show that marrow-extraction may have been a key subsistence strategy in the HP. In the post-HP, bone density-mediated attrition had a significant effect on fauna making it challenging to ascertain subsistence patterns, but preliminary analysis may also suggest marrow extraction in combination with other strategies.Post-depositional taphonomic marks such as manganese staining suggest that post-HP and late HP deposits were significantly more affected by moisture than the early HP deposits. Previous investigations of large mammal data point to more closed environments in the early HP, while our data indicate that the environment in the late HP and post-HP was largely similar. In comparing our data to previously analysed micromammal proxy data, we show that major environmental changes at KRM occurred after the shift to post-HP lithic technology. However, the taphonomic data suggests a close relationship between changing subsistence strategies and the MIS4/3 transition.

Antarctic ice cores reveal a glacial climate state during Marine Isotope Stage 3 (MIS‐3; 57–29 ka) punctuated by millennial‐scale warming events and pulses of CO2. This study further explores how changes in Southern Ocean carbon cycling contributed to these millennial‐scale fluctuations in climate. Evidence from South Atlantic sediment cores suggests that warming events were associated with decreased dust‐borne iron flux, reduced export production, and increased upwelling from the deep Southern Ocean (SO). These processes are considered to have contributed to rising atmospheric CO2 during periods of rapid warming. Here we investigate whether the same processes occurred in the southwest Pacific sector of the SO at TAN1106‐28. We show that reduced New Zealand glaciation and localized iron limitation in the southwest Pacific led to reduced export production during millennial‐scale warming events. Decreases in foraminifera‐bound δ15N during all MIS‐3 warming events may reflect increased nutrient supply by upwelling. Increased calcium carbonate flux during MIS‐3 warming events likely reflects coccolithophore production in response to sea surface temperatures, which, would increase carbonate counter pump strength and reduce CO2 sequestration. Concomitant decreases in bottom water oxygen, inferred from redox‐sensitive U and Mn sediment concentrations, and increases in the 14C age of deep waters, suggest that old, nutrient‐rich waters influenced southwest Pacific middepth waters during warming events. This signature may reflect an expansion of Pacific Deep Water into the SO during warming. Taken together, our multi‐proxy data set reveals that the southwest subantarctic Pacific acted as a source of CO2 during millennial‐scale warming events of MIS‐3. Plain Language Summary: Antarctic ice cores have provided evidence of episodes of warming and cooling of the Southern Hemisphere that took place over hundreds to thousands of years between 57,000 and 29,000 years ago. During warming events, the Southern Ocean is thought to have played a role in the increasing concentration of CO2 in the atmosphere. Here we use a sediment core from the southwest Pacific Southern Ocean to show that decreased iron input to the surface ocean reduced biological productivity during warming events, which hampered CO2 sequestration in the region. While in the deep ocean, proxies for the concentration of oxygen and the relative age of deep waters suggest that conditions may have become favorable for a release of CO2 from the ocean interior to the atmosphere during episodic warming. These findings support the theory that the Southern Ocean played an important role in the past carbon cycle by modulating the exchange of CO2 between the deep ocean and the atmosphere during periods of rapid climate change. Key Points: Decreased iron from New Zealand limits subantarctic Pacific export production during MIS‐3 warming eventsDecreases in foraminifera bound‐δ15N during MIS‐3 warming events are likely due to increased nutrient supply and reduced utilisationDecreases in bottom water O2 during MIS‐3 warming events may result from increased Pacific Deep Water influence [ABSTRACT FROM AUTHOR]

Recent technological advancements in spectral imaging core-scanning techniques have proved to be a promising tool to study lake sediments at extremely high resolution. We used this novel analytical approach to scan core AU3 of the Pleistocene Auel maar, Western Germany. The resulting ultra-high-resolution RABD670 spectral index, a proxy for the lake’s primary production, shows an almost complete succession of Greenland Interstadials of the NGRIP ice core chronology back to around 60,000 years. Using the ELSA-20 chronology and its anchor points to the NGRIP record as a stratigraphic basis, we were able to compare and fine-tune prominent climate signals occurring in both regions. This in-depth correlation yields strong evidence that the climates of Greenland and Central Europe were not only strongly coupled on timescales of stadials and interstadials but even on multidecadal scales, showing prominent climate cycles between 20 and 125 years. As climate changes in these regions were ultimately driven by variations in the North Atlantic meridional heat transport, their strong coupling becomes most apparent during cold and arid intervals. In contrast, longer-lasting warmer and more humid phases caused the activation of various regional feedback mechanisms (e.g., soil formation, forest growth), resulting in more complex patterns in the proxy records.

Establishing the timing of glacial and nonglacial intervals in the core regions of the Laurentide Ice Sheet (LIS) is essential to constrain ice-sheet configuration at times of globally reduced ice volume, such as during Marine Isotope Stage (MIS) 3 (~57-29 ka). Hudson Bay Lowland (HBL) deglaciation, at the centre of the LIS, has been inferred at MIS 3 based on near-infinite wood radiocarbon ages and limited luminescence ages. To better constrain the age of the penultimate deglaciation of the western HBL, this study initially identified the youngest intertill nonglacial sediments, based on extensive fieldwork and till characterization. Next, vetted radiocarbon ages were combined with revised stratigraphy to show that five previously identified "MIS 3" sites were likely deposited during an earlier ice-free period. Finally, new optical ages targeting the youngest intertill nonglacial bed at three localities yielded ages ranging from 166 to 146 ka; all older than MIS 3. These ages indicate that the penultimate deglaciation of the western HBL likely occurred during MIS 5e. This interpretation better explains accompanying paleobotanic data sets that indicate vegetation similar to vegetation existing under present interglacial conditions. Currently no firm evidence exists in the terrestrial stratigraphic record for the deglaciation of the western HBL during MIS 3. [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]

We present a record of pollen and spores of coprophilous fungi from a sediment core from Auel infilled maar, Eifel, Germany, covering the period from 42,000 to 36,000 yr b2k. We can show that vegetation cover was dominated by a boreal forest with components of steppe and cold-temperate wood taxa. The proportion of wood taxa was higher during interstadials, whereas steppe-vegetation became more prominent during stadials. During Heinrich stadial 4, temperate taxa are mostly absent. Spores of coprophilous fungi show that megaherbivores were continuously present, albeit in a larger number during stadials when steppe environment with abundant steppe herbs expanded. With the onset of Greenland stadial 9, forests became more open, allowing for steppe-environment to evolve. The shift in vegetation cover coincides with the highest values of herbivore biomass at the time that Neanderthal humans demised and Anatomically Modern Humans most probably arrived in Central and Western Europe. Megaherbivore biomass was a direct consequence of vegetation cover/availability of food resources and thus an indirect consequence of a changing climate. Herds of large herbivores following suitable (steppe) habitats may have been one cause of the migration of AMH into Europe, going along with their prey to productive hunting grounds. [ABSTRACT FROM AUTHOR]

We analyzed mineralogical characteristics, and major as well as rare earth element concentrations, from a cryptotephra layer in sediments of the infilled maar of Auel (Eifel, Germany). The results of detailed geochemical analyses of clinopyroxenes and their glassy rims from the Auel cryptotephra layer showed that they are similar to those from the thick Campanian Ignimbrite tephra occurrence in a loess section at Urluia (Romania). Both tephras show idiomorphic green clinopyroxenes and formation of distorted grains up to millimeter scale. The cryptotephra in the Auel core has a modelled age of around 39,940 yr b2k in the ELSA-20 chronology, almost identical to the latest 40Ar/39Ar dates for the Campanian Ignimbrite/Y-5 (CI/Y-5) eruption. These observations suggest that parts of the CI/Y-5 ash cloud were transported also northwestward into Central Europe, whereas the main branch of the CI/Y-5 ash plume was transported from southern Italy towards the NE, E, and SE. Based on pollen analyses, we conclude there was no direct effect on vegetation from the CI/Y-5 fallout in the Eifel area. Trees, shrubs, and grasses remained at pre-tephra-airfall levels for roughly 240 years, but changed around 39,700 yr b2k when thermophilic woody plants (e.g., Alnus and Carpinus) disappeared and Artemisia spread. This change in vegetation was well after the Laschamp geomagnetic excursion and also after the GI9 interstadial and quite probably represents the onset of the Heinrich Event 4 (H4) cold spell, when climatic conditions over the North Atlantic, and apparently also in Central Europe, deteriorated sharply.

Regions located on the Chinese Loess Plateau are sensitive to changes in the Asian monsoon because they are on the edge of the monsoon region. Based on six 230Th experiments and 109 sets of stable isotope data of LH36 from Lianhua Cave, Yangquan City, Shanxi Province, we obtained a paleoclimate record with an average resolution of 120 years from 54.5 to 41.1 ka BP during the MIS3 on the Chinese Loess Plateau. Both the Hendy test and the replication test indicated an equilibrium fractionation of stable isotopes during the stalagmite deposition. Comparison with four other independently-dated, high-resolution stalagmite δ13C records between 29°N and 41°N in the Asian monsoon region shows that the stalagmite δ13C records from different caves have good reproducibility during the overlapped growth period. We suggest that speleothem δ13C effectively indicates soil CO2 production in the overlying area of the cave, reflecting changes in the cave's external environment and in the Asian summer monsoon. Five millennial-scale Asian summer monsoon intensification events correspond to the Dansgaard–Oeschger 10–14 cycles recorded in the Greenland ice core within dating errors, and the weak monsoon processes are closely related to stadials in the North Atlantic. The spatial consistency of stalagmite δ13C records in China suggests that the Asian summer monsoon and the related regional ecological environment fluctuations sensitively respond to climate changes at northern high latitudes through sea-air coupling on the millennial timescale. [ABSTRACT FROM AUTHOR]

The acquisition of large prey by hominins living during the Marine Isotope Stage 3, including Neanderthals and Anatomically Modern Humans, had nutritional and bioenergetic implications: these contain high fat amounts, provide a high energy return, and the strategies and skills required to acquire small prey were different from those required to acquire the former. Vitamin C availability at several MIS 3 periods could have had a strong seasonal variability and would have been decisive for hominin groups' survival. During the cold periods of the MIS 3, Paleolithic hominins had variable available amounts of vitamin C-containing plants only in the short summers, and for the remainder of the year, viscera would have been their best source of vitamin C. Meanwhile, the dependence on small mammals could have caused an erratic distribution of viscera to be consumed by such hominins, thus leading to chronic scurvy, and compromising their survival. Then, the hunting of large mammals would have helped to meet the daily vitamin C needs, besides an efficient energy supply. Therefore, the decline of large prey during the MIS 3 could have been critical for hominins survival, and thus the efficient exploitation of alternative vitamin C-rich food resources such as birds and aquatic animals could have favored the evolutionary success of hominin populations. [ABSTRACT FROM AUTHOR]

Global mean sea level (GMSL) during intermediate interglacial Marine Isotope Stage 3 (MIS 3) (60–26 ka) has proven difficult to constrain. Paleo‐sea level estimates based on ice margin, modeling, and paleo‐shoreline reconstructions indicate that MIS 3 GMSL was substantially higher than reconstructed from deep‐ocean benthic foraminifera oxygen isotope (δ18O) and coral records, implying much smaller ice sheets during MIS 3. Here, we use the δ18O and Mg/Ca chemistry of surface and thermocline dwelling foraminifera in the Sulu Sea in the western Pacific margin to estimate relative changes of the influx of South China Sea surface flow through the Sulu Sea over the last 140 ka. We show that this South China Sea throughflow is controlled in part by changes in GMSL modulating the depth of the 36 m deep Karimata Strait at the southern end of the South China Sea. We constrain maximum allowable GMSL at the beginning and end of MIS 3 to −22 ± 6 and −29 ± 5 m, respectively, and minimum allowable GMSL during interglacial stages MIS 5c and 5a (117–72 ka) to range from −3 ± 8 to −8 ± 8 m and −11 ± 7 to −12 ± 7 m, respectively. Our results constrain MIS 3 GMSL, but do not rule out higher MIS 3 ice margin, modeling, and paleo‐shoreline‐based MIS 3 GMSL estimates or lower coral and seawater δ18O‐based estimates. Our results favor the highest MIS 5a and 5c GMSL estimates and confirm that the Sunda Shelf served as a land‐bridge for human and megafauna migration during MIS 3 when humans first arrived in Borneo. Key Points: Sulu Sea surface salinity records Karimata Strait inundation since 125 ka and in combination with strait depth, constrains sea levelA subaerial Karimata Strait during Marine Isotope Stage 3 (MIS 3) may have aided human migration to Borneo and shows Global mean sea level (GMSL) was lower than −22 ± 3 mThe Karimata Strait was inundated during MIS 5a and 5c, and GMSL was above −12 ± 7 m relative to today [ABSTRACT FROM AUTHOR]

We present a record of pollen and spores of coprophilous fungi from a sediment core from Auel infilled maar, Eifel, Germany, covering the period from 42,000 to 36,000 yr b2k. We can show that vegetation cover was dominated by a boreal forest with components of steppe and cold-temperate wood taxa. The proportion of wood taxa was higher during interstadials, whereas steppe-vegetation became more prominent during stadials. During Heinrich stadial 4, temperate taxa are mostly absent. Spores of coprophilous fungi show that megaherbivores were continuously present, albeit in a larger number during stadials when steppe environment with abundant steppe herbs expanded. With the onset of Greenland stadial 9, forests became more open, allowing for steppe-environment to evolve. The shift in vegetation cover coincides with the highest values of herbivore biomass at the time that Neanderthal humans demised and Anatomically Modern Humans most probably arrived in Central and Western Europe. Megaherbivore biomass was a direct consequence of vegetation cover/availability of food resources and thus an indirect consequence of a changing climate. Herds of large herbivores following suitable (steppe) habitats may have been one cause of the migration of AMH into Europe, going along with their prey to productive hunting grounds.

Several millennial-scale warm phases perturbed the glacial climate during Marine Isotope Stage 3 (MIS 3, ca. 57–29 ka BP). Little is known about the impact of these climatic changes on Alpine ecosystems due to the sparsity of undisturbed sediment records in the Alps and their foreland. In this study, multiple sediment-archived proxies (sediment geochemistry, stable oxygen and carbon isotopes of autochthonous carbonate, and subfossil remains of macrophytes and aquatic invertebrates) were examined in five drill cores from an ancient inner-Alpine lake at Unterangerberg (Eastern Alps) to reconstruct the palaeolake environment and to estimate summer temperature changes for the first half of MIS 3. The lacustrine sedimentation in the basin began ca. 54.6 ka, tentatively correlated with the start of Greenland Interstadial (GI) 14. We identified three distinct phases in the development of the lake. (1) A cold, oligotrophic water body influenced by snow/glacier meltwater ca. 54.6–52.2 cal ka BP. (2) A clear-water, macrophyte-dominated, productive lake ca. 52.2–44.9 cal ka BP. Submerged macrophytes were dominated by the charophyte alga Chara hispida and chironomid assemblages – by Corynocera ambigua, which is absent from the present-day fauna of the Alpine region. (3) A turbid-water, less productive lake ca. 44.9–41.5 cal ka BP. This shift towards a turbid-water state, as evidenced by the drastic reduction in the abundance of submerged macrophytes and associated invertebrates, likely occurred due to increased input of meltwater. The regime shift is tentatively correlated with the start of GI 11, for which the highest temperatures of the studied MIS 3 interval are inferred. Chironomid-based reconstructions of mean July air temperatures provide interstadial temperature estimates between ca. 11 and 12.5°C (i.e. ca. 5–6°C below present-day values), which concurs with reconstructions available from the northern Alpine foreland. Cooler July temperatures (ca. 9–10°C) are reconstructed for MIS 3 stadials. The Unterangerberg lacustrine records provide valuable new insights into MIS 3 climate dynamics inside the Eastern Alps and contribute to a better understanding of the effects of climate change on the Alpine environment.

The acquisition of large prey by hominins living during the Marine Isotope Stage 3, including Neanderthals and Anatomically Modern Humans, had nutritional and bioenergetic implications: these contain high fat amounts, provide a high energy return, and the strategies and skills required to acquire small prey were different from those required to acquire the former. Vitamin C availability at several MIS 3 periods could have had a strong seasonal variability and would have been decisive for hominin groups’ survival. During the cold periods of the MIS 3, Paleolithic hominins had variable available amounts of vitamin C-containing plants only in the short summers, and for the remainder of the year, viscera would have been their best source of vitamin C. Meanwhile, the dependence on small mammals could have caused an erratic distribution of viscera to be consumed by such hominins, thus leading to chronic scurvy, and compromising their survival. Then, the hunting of large mammals would have helped to meet the daily vitamin C needs, besides an efficient energy supply. Therefore, the decline of large prey during the MIS 3 could have been critical for hominins survival, and thus the efficient exploitation of alternative vitamin C-rich food resources such as birds and aquatic animals could have favored the evolutionary success of hominin populations.

Abstract The climate of the western Mediterranean was characterized by a strong precipitation gradient during the Holocene driven by atmospheric circulation patterns. The scarcity of terrestrial paleoclimate archives has precluded exploring this hydroclimate pattern during Marine Isotope Stages 5 to 3. Here we present stable carbon and oxygen isotope records from three flowstones from southeast Iberia, which show that Dansgaard/Oeschger events were associated with more humid conditions. This is in agreement with other records from the Iberian Peninsula, the Mediterranean, and western Europe, which all responded in a similar way to millennial‐scale climate variability in Greenland. This general increase in precipitation during Dansgaard/Oeschger events cannot be explained by any present‐day or Holocene winter atmospheric circulation pattern. Instead, we suggest that changes in sea surface temperature played a dominant role in determining precipitation amounts in the western Mediterranean.

The ocean floor sedimentological signature of Heinrich event 3 (H3) is markedly different from that of other Heinrich events that are known to have originated in Hudson Strait. It has therefore been suggested that the H3 contribution to iceberg flux may have been delivered by ice streams located in the eastern sector of the North Atlantic, from the Fennoscandian or British Isles ice sheets. To investigate this possibility and whether the instability involved may have been tidally induced, as seems to have been the case for H1, we consider several eastern Atlantic sector possibilities: a hypothetical Barents Sea ice stream, the Norwegian ice stream, and the Irish Sea ice stream. We find that the extremely high amplitude of the M2 tidal constituent in the western North Atlantic that appears to have forced H1 did not exist in the northeastern Atlantic. This suggests that, with one possible exception, if destabilized ice streams in this region did contribute to H3, tidal forcing was most probably not the cause. The single exception to this general conclusion may be the Irish Sea ice stream, and we comment on the probability of a contribution to H3 from this source. [ABSTRACT FROM AUTHOR]

We present a mechanism for self‐sustained ocean circulation changes that cause abrupt temperature changes over Greenland in a multimillennial climate model simulation with glacial CO2 concentrations representative of Marine Isotope Stage 3. The Atlantic meridional overturning circulation (AMOC) and the subpolar gyre (SPG) oscillate on millennial time scales. When the AMOC is strong, the SPG is weak and contracted; when the AMOC is weak, the SPG is strong and extensive. The coupling between the two systems via wind‐driven and density‐driven feedbacks is key to maintaining the oscillations. The SPG controls the transport of heat and salt into the deep‐water formation sites and thus controls the AMOC strength. The strength and location of the deep‐water formation affect the density‐driven part of the SPG and thus control the mean strength and extent of the SPG. This mechanism supports the hypothesis that coupled ocean‐ice‐atmosphere interactions could have triggered abrupt glacial climate change. Plain Language Summary: Between 57.000 and 29.000 years ago, the last glacial period was marked by several abrupt warming and cooling events over Greenland and the North Atlantic. Understanding the mechanism behind these so‐called Dansgaard‐Oeschger events increases our understanding of possible tipping points that cause abrupt change in the Earth system. The role of the ocean in causing these events is still a topic of debate. We find abrupt changes in the North Atlantic circulation that resemble Dansgaard‐Oeschger events in a simulation with a state‐of‐the‐art climate model. These simulated ocean circulation changes are generated without adding external triggers such as meltwater from glaciers. Instead, the events are generated by the interaction of the two large‐scale current systems in the North Atlantic—the Atlantic meridional overturning circulation (AMOC) and the North Atlantic subpolar gyre (SPG). Both current systems are affected by changes in surface winds and the density pattern of the North Atlantic. We find that the location where the densest water is formed controls how the SPG interacts with the AMOC. Under favorable conditions, the effects of wind and density combine in such a way that changes in the SPG cause abrupt changes in the AMOC. Key Points: Millennial‐scale, self‐sustained oscillations of the ocean circulation occur in a climate model simulationThe oscillations are driven by the interaction between the Atlantic meridional overturning circulation (AMOC) and the subpolar gyre (SPG)The AMOC‐SPG coupling is controlled by a wind‐driven and a density‐driven feedback; the coupling sign depends on the dominant feedback [ABSTRACT FROM AUTHOR]

The Antarctic Ice Sheet (AIS) is the largest potential source for future global sea level rise. However, there are widely diverging estimates of its contribution, which emphasizes the need to improve our understanding of the long‐term behavior of the AIS and its impact on the solid Earth. This knowledge gap results from a shortage of records of glacial history, especially for the pre‐Holocene. Marine transgression and recession in the coastal areas of Antarctica are influenced by the mass of the overlying ice, providing crucial information about regional ice sheet dynamics. In this study, we determined a marine transgression from 53 kyr BP onward by diatom assemblages and a δ13C‐C/N biplot for the organic component in a sediment core (MCM2), from the Larsemann Hills in East Antarctica. Relative sea level (RSL) reached a maximum of ~12 m a.p.s.l. (above present sea level) during 38–29 kyr BP. Concurrent with the transgression, the regional crust experienced glacial‐isostatic‐adjustment (GIA)‐induced subsidence from ~75 to ~95 m beneath the present land level, suggesting an expansion trend of the East Antarctic ice sheet (EAIS), which may have outpaced global cooling. After the last deglaciation, the RSL rose to a highstand of ~8–10 m a.p.s.l. at ~8.5–7.1 kyr BP, when the bedrock uplifted to ~20 m below the present level. After 4.0 kyr BP, both regional and global deglaciation ceased, but an effect of ongoing relaxation caused the land to rebound continuously at a uniform rate of ~1.5 m/kyr, which can account for the sustained fall of RSL across Antarctica since mid‐Holocene. Key Points: A marine transgression period was constrained to 53–29 kyr BP at the Larsemann Hills, East AntarcticaWe provide a synthesis of the relative sea level changes and GIA‐induced displacement of the Larsemann Hills in the last 50 kyrThe ongoing relaxation process of GIA account for the sustained fall of the relative sea level since mid‐Holocene [ABSTRACT FROM AUTHOR]

The mechanisms controlling changes in atmospheric circulation and rainfall over the Indo‐Pacific Warm Pool (IPWP) on glacial‐interglacial timescales remain a subject of considerable debate. Continental shelf exposure, through sea‐level drawdown during glacial periods, has been proposed as an important and possibly dominant control on rainfall intensity over the IPWP and Indian Ocean. However, longer records of hydroclimate change undermine this shelf exposure hypothesis. In particular, trends in some proxy records of rainfall do not track the extent of continental shelf exposure inferred from global benthic oxygen isotope records during Marine Isotope Stage 3 (MIS 3). We revisit the hypothesis that continental shelf exposure controls IPWP precipitation using the latest constraints on ice‐age sea level. Recent studies on the timing and magnitude of global mean sea level during mid‐MIS 3 (~45) suggest significantly higher peak sea level relative to previous work. Our gravitationally self‐consistent glacial isostatic adjustment sea‐level reconstructions, which adopt recent constraints on MIS 3 sea level, predict a transition from widely inundated to exposed shelves in the Indo‐Pacific region from mid‐MIS 3 to the beginning of the Last Glacial Maximum (LGM, ~19–26 ka). Over this same time period, proxy records of vegetation and hydrology from central Indonesia suggest a transition from wetter conditions during mid‐MIS 3 to drier conditions during the LGM. Our new calculations thus negate prior criticisms related to the timing and extent of shelf exposure, indicating that shelf exposure may remain an important driver for hydroclimate variability in the IPWP region on glacial‐interglacial timescales. Key Points: Recent constraints suggest higher MIS 3 global mean sea level than in prior reconstructionsWe calculate continental shelf exposure in the Sunda and Sahul shelves from MIS 3 to the Last Glacial MaximumOur results negate prior criticisms of the hypothesis that continental shelf exposure controls rainfall variability over the Indo‐Pacific [ABSTRACT FROM AUTHOR]

This paper summarizes the current state of knowledge about the millennial scale climate variability characterizing Marine Isotope Stage 3 (MIS 3) in S-Europe and the Mediterranean area and its effects on terrestrial ecosystems. The sequence of Dansgaard-Oeschger events, as recorded by Greenland ice cores and recognizable in isotope profiles from speleothems and high-resolution palaeoecological records, led to dramatic variations in glacier extent and sea level configuration with major impacts on the physiography and vegetation patterns, both latitudinally and altitudinally. The recurrent succession of (open) woodlands, including temperate taxa, and grasslands with xerophytic elements, have been tentatively correlated to GIs in Greenland ice cores. Concerning colder phases, the Greenland Stadials (GSs) related to Heinrich events (HEs) appear to have a more pronounced effect than other GSs on woodland withdrawal and xerophytes expansion. Notably, GS 9-HE4 phase corresponds to the most severe reduction of tree cover in a number of Mediterranean records. On a long-term scale, a reduction/opening of forests throughout MIS 3 started from Greenland Interstadials (GIs) 14/13 (ca. 55–48 ka), which show a maximum in woodland density. At that time, natural environments were favourable for Anatomically Modern Humans (AMHs) to migrate from Africa into Europe as documented by industries associated with modern hominin remains in the Levant. Afterwards, a variety of early Upper Palaeolithic cultures emerged (e.g., Uluzzian and Proto-Aurignacian). In this chronostratigraphic framework, attention is paid to the Campanian Ignimbrite tephra marker, as a pivotal tool for deciphering and correlating several temporal-spatial issues crucial for understanding the interaction between AMHs and Neandertals at the time of the Middle to Upper Palaeolithic transition. [ABSTRACT FROM AUTHOR]

The Huangniliang site, located in the coastal province of Shandong, in North China, was excavated in 2013. Optically stimulated luminescence results show that the age of the deposits ranges from 59 to 54 ka, corresponding to the initial part of Marine Isotope Stage (MIS) 3. This study introduces the detailed analyses of the stone artefacts from the site, and provides a review of the major Paleolithic sites dated to early MIS 3 in North China. Analyses of the Huangniliang lithic assemblage show that the principal flaking technique was direct hard-hammer percussion, but core preparations and systematic percussion are also present. A series of assemblages in North China show a diversified scenario before the Late Paleolithic (LP). Dominated by the simple flake-core tradition, lithic industries in northern China dated to 35–60 ka occasionally include a Mousterian-like industry, a macroblade technology, Acheulian-type large cutting tools, systematic percussion and diversified toolkits. Lithic technological organization expressed by systematic percussion and incipient organization on the land-use expressed by the organized acquisition of raw materials during early MIS 3 are indicators of behavioral complexity. [ABSTRACT FROM AUTHOR]

The climate of the western Mediterranean was characterized by a strong precipitation gradient during the Holocene driven by atmospheric circulation patterns. The scarcity of terrestrial paleoclimate archives has precluded exploring this hydroclimate pattern during Marine Isotope Stages 5 to 3. Here we present stable carbon and oxygen isotope records from three flowstones from southeast Iberia, which show that Dansgaard/Oeschger events were associated with more humid conditions. This is in agreement with other records from the Iberian Peninsula, the Mediterranean, and western Europe, which all responded in a similar way to millennial‐scale climate variability in Greenland. This general increase in precipitation during Dansgaard/Oeschger events cannot be explained by any present‐day or Holocene winter atmospheric circulation pattern. Instead, we suggest that changes in sea surface temperature played a dominant role in determining precipitation amounts in the western Mediterranean. Plain Language Summary: Climate events characterized by a sudden temperature increase of up to 10 °C occurring in less than a few decades during the last glacial are recorded in Greenland ice cores. These abrupt warmings, the Dansgaard/Oeschger events, affected large regions of the Northern Hemisphere. The understanding of the regional response in precipitation during these climate shifts is limited for the western Mediterranean, due to the restricted number of terrestrial climate records that cover the last glacial period at sufficient resolution. Speleothems and their stable isotope compositions allow to trace changes in climate and vegetation based on an accurate chronological framework. Here we present a speleothem stable isotope record that shows that the Dansgaard/Oeschger events were associated with increased rainfall and a denser vegetation in the western Mediterranean. A similar pattern was observed for western Europe and other parts of the Mediterranean, and we propose that this was related to generally higher sea surface temperatures of the surrounding oceans rather than a reorganization of atmospheric circulation. Key Points: Western Mediterranean precipitation responded to Greenland interstadials and stadials in a coherent mannerDansgaard/Oeschger interstadials were accompanied by humid climate conditions over the western MediterraneanAtmospheric circulation patterns did not induce spatial differences in precipitation during the last glacial as they did during the Holocene [ABSTRACT FROM AUTHOR]

To advance our understanding of the responses of tropical cyclones (TCs) to abrupt climate transitions, we investigate the variation of genesis potential and the underlying mechanisms during Marine Isotope Stage 3 (MIS 3) that is characterized by frequent millennial-scale oscillations, using a set of coupled model simulations. We illustrate that genesis potential mainly increases over the eastern North Pacific and South Pacific in the storm season during MIS 3 interstadial relative to preindustrial, whereas it decreases over the western North Pacific, North Atlantic, South Indian Ocean, and Australian coast. The relative importance of each genesis factor to genesis potential change varies across oceans. During the transition from warm interstadial to cold stadial induced by freshwater injection, TC genesis potential generally decreases in the Northern Hemisphere, while increases in the Southern Hemisphere. These changes are associated with asymmetric variations of genesis factors between Northern and Southern Hemisphere, which are further tied to the adjustment of large-scale environmental factors in response to the weakened Atlantic meridional overturning circulation. Additionally, TC genesis potential exhibits a regional "overshoot" phenomenon when the freshwater injection is terminated, manifested by an increase over the eastern North Pacific and North Atlantic and a decrease over the South Pacific, compared with the initial interstadial state. Our results may help improve our knowledge on past TC behaviors and shed lights on TC response to potential abrupt climate transitions in a warmer future. • The variations of genesis potential vary across oceans during MIS 3 interstadial. • Hemisphere-asymmetric response of genesis potential during warm–cold transition. • An "overshoot" phenomenon in genesis potential during climate transition recovery. [ABSTRACT FROM AUTHOR]

Moisture transportation to (semi-)arid Central Asia is influenced by the interplay of multiple atmospheric circulation patterns. The mechanism underlying the hydroclimate evolution in CA has recently received increasing attention. In northeastern CA, most of the precipitation falls in summer, counter to other westerly-dominated regions of CA where precipitation maximizes in boreal winter. The marine isotope stage (MIS) 3 offers a unique opportunity to examine the mechanisms driving hydroclimate variations during warm periods of the ice age in the CA. However, due in part to reliable proxies for reconstruction, the hydroclimate and vegetation change during MIS3 in northeastern CA have not been well studied. Here, we use grain size and magnetic susceptibility data from the Zeketai loess profile to reconstruct historical shifts in precipitation patterns during MIS3 in the Ili Basin from arid Central Asia (ACA). Notably, abrupt changes around 35 ka are evident in the grain size and magnetic susceptibility records, reflecting a transition to reduced wind intensity and increased aridity. Subsequent analysis of plant leaf waxes (n -alkanes), hydrogen isotopic composition of n -alkanes (δD n -alkane), and stable carbon isotope ratios of total organic carbon (δ13C org) within the loess profile indicates a concurrent shift towards more shrubs, aligning with reduced moisture availability. The δ13C org record further elucidates that during MIS3, the Ili Basin predominantly harbored C 3 vegetation. However, the alteration in δ13C org and δD n -alkane to more positive values at approximately 35 ka substantiates the transition to more drought-resistant vegetation. Furthermore, we link the paleo-hydroclimate variations to the decrease in solar radiation and the strengthening of the Atlantic Meridional Overturning Circulation (AMOC) and Siberian High during late MIS3. This joint influence weakens the Westerly winds and subsequently diminishes the conveyance of moisture to CA. • Loess proxies indicate increased aridity in Central Asia during late MIS3. • Reduced moisture transport to Central Asia linked to stronger AMOC. • Aridification caused an abrupt shift towards more woody vegetation. [ABSTRACT FROM AUTHOR]

Abstract To understand sea-level changes since the Last Glacial Maximum (LGM) and their effects on coral reef systems, the shelf-edge slopes of the Great Barrier Reef (GBR) were cored during the Integrated Ocean Drilling Program (IODP) Expedition 325. Recovered unconsolidated sediments beneath the submerged shelf edge reefs contain abundant foraminiferal tests, which record changes in depositional environments and paleo-water depths. A total of 177 sediment samples were collected from 17 holes along three transects located within two geographical areas (Noggins Pass and Hydrographers Passage), and were analyzed to determine stratigraphic changes in foraminiferal assemblages (2–0.5 mm size fraction). Results show that four foraminiferal assemblages (A, B, C and D) are delineated by multivariate analyses (Q-mode cluster analysis and non-metric multidimensional scaling: NMDS), and these assemblages correspond to a back-reef to reef margin zone (0–10 m deep; Assemblage A), an upper photic zone (10–30 m deep) associated with hard substrates (Assemblage B), an intermediate to lower photic zone (30–90 m deep) characterized by soft substrates (Assemblage C), and a lower photic zone (90–130 m deep) only found in modern shelf slopes (Assemblage D). Gradual shifts in these four foraminiferal assemblages superimposed on a two-dimensional NMDS ordination mainly reflect water-depth gradients and the relative dominance of two substrate types (hard and soft substrates). Pre-LGM (older than Marine Isotope Stage 3: ≥MIS3) sediments along transects at Hydrographers Passage were deposited at intermediate to lower photic zones. In contrast, relatively shallow-water sequences found in ≥MIS3 deposits at Noggins Pass likely owe their origin to either turbidite and/or land slide processes. The lack of Assemblage D in ≥MIS3 deposits from all transects could be related to lowering temperature and/or increasing terrestrial influences (i.e. more light attenuation). Shallowing upward sequences found in LGM (MIS 2) deposits at Hydrographers Passage are likely related to stepwise sea-level falls to the full extent of the LGM. These foraminifer-based paleoenvironmental interpretations suggest that the GBR shelf edge slopes have changed their depositional environments continuously in response to sea-level fluctuations during the last glacial cycle. Highlights • GBR shelf-edge sediment cores contain four distinct foraminiferal assemblages. • Four GBR foraminiferal assemblages reflect variations in water depth and substrate. • ≥MIS3 depositional environments differ between Noggins Pass and Hydrographers Passage. • Upward shallowing LGM deposits are related to stepwise sea-level falls. [ABSTRACT FROM AUTHOR]

Abstract Marine Isotope Stage 3 (MIS 3, 57–27 ka) was characterised by numerous rapid climate oscillations (i.e., Dansgaard-Oeschger (D/O-) events), which are reflected in various climate archives. So far, MIS 3 speleothem records from central Europe have mainly been restricted to caves located beneath temperate Alpine glaciers or close to the Atlantic Ocean. Thus, MIS 3 seemed to be too cold and dry to enable speleothem growth north of the Alps in central Europe. Here we present a new speleothem record from Bunker Cave, Germany, which shows two distinct growth phases from 52.0 (+0.8, −0.5) to 50.9 (+0.6, −1.3) ka and 47.3 (+1.0, −0.6) to 42.8 (±0.9) ka, rejecting this hypothesis. These two growth phases potentially correspond to the two warmest and most humid phases in central Europe during MIS 3, which is confirmed by pollen data from the nearby Eifel. The hiatus separating the two phases is associated with Heinrich stadial 5 (HS 5), although the growth stop precedes the onset of HS 5. The first growth phase is characterised by a fast growth rate, and Mg concentrations and Sr isotope data suggest high infiltration and the presence of soil cover above the cave. The second growth phase was characterised by drier, but still favourable conditions for speleothem growth. During this phase, the δ13C values show a significant decrease associated with D/O-event 12. The timing of this shift is in agreement with other MIS 3 speleothem data from Europe and Greenland ice core data. Highlights • Speleothem record from central Europe covering MIS 3. • 230Th/U dating shows two distinct growth phases during early MIS 3. • Growth stop is likely related to the Heinrich 5 event. • Multi-proxy data suggest humid phases during growth periods in MIS 3. [ABSTRACT FROM AUTHOR]

The Abric Romaní site (Capellades, Barcelona, Spain) constitutes a key site for understanding the latest Neanderthal occupations in Western Europe. Here we present a comprehensive systematic and taphonomic analysis of a small-mammal assemblage from Level O of the Abric Romaní site, with the aim of reconstructing the paleoecological context in which the Neanderthals lived. The assemblage, which probably dates from a stadial episode between Interstadial 15 and Interstadial 14, contains fifteen small mammal species, including species uncommon for the northeast of Iberia, such as Sciurus vulgaris , Nyctalus lasiopterus and Pipistrellus pipistrellus . Taphonomic studies suggest a predatory origin for the assemblage, probably related to Strix aluco , and paleoecological inferences suggest lower temperatures (−3/−4 °C) and higher rainfall (+70/+170 mm) than at present and a landscape dominated by an open forest with watercourses. The new data improve our knowledge of trends associated with Marine Isotope Stage 3 that affected Neanderthal populations in the Iberian Peninsula, showing that the Neanderthals were well adapted to cooler and wetter conditions across Iberia. [ABSTRACT FROM AUTHOR]

Research into the geographical distribution of temperate tree refugia and their associated environmental conditions during glacial stages is necessary to understand the processes by which the present vegetation and plant distributions developed. On the basis of pollen and plant macrofossil assemblages deposited in a small valley in a hill in the northern Kanto district in central Japan, we reconstructed the local and regional vegetation changes in and around the distribution range limit of temperate broadleaf trees during the latest stage of marine isotope stage (MIS) 3 (36.2–32.8 ka) and around the late stage of the last glacial maximum (LGM) (23.4–16.6 ka). During the latest stage of MIS 3, the local and regional vegetation in and around the hill was composed of temperate deciduous broadleaf forest dominated by Quercus subgen. Lepidobalanus and mixed with pinaceous conifers. The proportion of deciduous broadleaf trees in the regional vegetation increased during recurring warm and humid phases that were correlated with Greenland D-O 7, 6, and 5 warming events. During the LGM, coniferous forests composed of Picea jezoensis var. hondoensis , Tsuga diversifolia , Abies veitchii , and Betula ermanii , which are major components of the present subalpine forests in central and western Japan, expanded in hilly and mountain zones in central Japan. Refugia of temperate broadleaf trees existed at altitudes up to that of the study site and were limited to mesic places along the valley bottom. At the termination of the LGM around 18.8 ka, a biome shift to mixed coniferous and deciduous broadleaf forest dominated by Betula occurred in and around the study site. The expansion of deciduous broadleaf trees at ca. 19 ka, which has also been recognized in other localities in central Japan, may have been triggered by an increase in precipitation during the stage wherein summer insolation became greater. The temperate broadleaf trees that have been distributed in hilly-zone refugia were sensitive to warming at the termination of the LGM. [ABSTRACT FROM AUTHOR]

In this paper, we present new evidence regarding a Marine Isotope Stage 3 (MIS3) transgression on the south-eastern Brazilian coast (Baixada Santista coastal plain). Data collected from a Standard Penetration Test (SPT) drilling reveal the occurrence of myxohaline sediments between cal BP 45,000 and 41,000. A deeper sequence, which shows a clear transition from terrestrial to a myxohaline environment, was associated with MIS5e. Organic and inorganic proxies have been used to recognize the variations on the terrestrial/myxohaline/marine deposits, as well as to infer about climate and energy of the depositional environment. Environmental change, which could correspond to a sea-level peak or the occurrence of drier conditions, was recognized between 43,000 and 42,000 cal BP. The results reinforce the need for future works on MIS3 variability on the South American Atlantic coast. [ABSTRACT FROM AUTHOR]

In this study, we analyzed 5α(H)-stanol/Δ 5 -sterol ratios in offshore marine sediments using offline tetramethylammonium hydroxide thermochemolysis (TMAH) gas chromatography–mass spectrometry (GC–MS). Data were used to reconstruct redox events recorded in a southern California marine sediment core (Ocean Drilling Program, Leg167, Hole 1017E). The 24-nordehydrocholestanol/24-nordehydrocholesterol and diatomstanol/diatomsterol ratios clearly recorded oxygen minimum zone (OMZ) fluctuations in southern California during the last 40 kyr. In particular, two ratios corresponding to Marine Isotope Stage 3 (MIS3) varied significantly at the OMZ, exhibiting millennial-scale fluctuations related to Dansgaard-Oeschger shifts of warming and cooling intervals. In contrast, other ratios (cholestanol/cholesterol, campestanol/campesterol, sitostanol/sitosterol, and 22-dehydrocholestanol/22-dehydrocholesterol) showed no significant trends, possibly reflecting the influence of stanol-creating organisms. Our results show that 5α(H)-stanol/Δ 5 -sterol ratios obtained using the TMAH GC–MS method are useable tracers of water column and surface sediment redox conditions in southern California marine sediments. [ABSTRACT FROM AUTHOR]

The Early to Late Paleolithic transition in eastern Asia is a topic receiving increasing attention in paleoanthropology. Here, we present the findings from Galsanri, an early Late Paleolithic open-air site that dates to the latter part of marine isotope stage 3 in South Korea. Findings from Galsanri suggest the Early to Late Paleolithic behavioral transition was unlikely to have been the result of a simple mass dispersal event from western Eurasia into eastern Asia. The Galsanri lithic assemblage includes typical Early Paleolithic core and flake tools in the same context as Late Paleolithic blades produced on low-quality raw materials and ground stone tools. The implications of the Galsanri findings are discussed in their broader behavioral contexts. [ABSTRACT FROM AUTHOR]

This report describes an isolated right horn core of a fossil steppe bison ( Bison priscus ) recovered from Late Pleistocene deposits near Langsdorf in the federal state of Mecklenburg-Vorpommern (Germany). AMS radiocarbon dating provided an age of 45353 ± 2894 cal yr BP for the specimen. The horn core, which by morphological criteria belonged to a female, has two depressions in its basal portion that differ in size, shape, and depth. While depressions are known from horn cores of domestic cattle, sheep, and goats, this is the first case reported from a wild bovid. Formation of the depressions on the steppe bison’s horn core likely was caused by localized bone resorption during periods of increased demand for mineral elements that could not be met by dietary uptake. Such situations may have occurred in relation to pregnancy and/or lactation. Pronounced bone resorption as a means to mobilize skeletally stored mineral elements was observed in other mammals, too. Since horn cores are recovered frequently among skeletal remains of fossil bison, a systematic inspection of fossil collections for similar horn core depressions is encouraged. [ABSTRACT FROM AUTHOR]

Palynology of fossil faeces is still extremely rare and its contribution to the interpretation of the environment undervalued. In this paper we present the results of pollen analysis performed on cave hyena coprolites [ Crocuta crocuta spelaea (Goldfuss, 1832)] from Marine Isotope Stage 3 (MIS 3) sites of Cava Muracci (Cisterna di Latina, central Italy) and Tana delle Iene (Ceglie Messapica, southern Italy). This study provides new insights into the vegetation of the Late Pleistocene of peninsular Italy, until now known only through long pollen records. It also shows how the content of coprolites, combined with faunal data and geochronological investigations, can represent a potential integrative source of palaeoclimatic proxy data. Our results indicate that the surroundings of both of the hyena dens were characterised by a patchy landscape with open lowlands dominated by steppe and grassland vegetation, while a few mesophilous and thermophilous trees were present in more humid areas, probably along the marine coast and inland. The harsh glacial climate appears to have been milder at Cava Muracci than at Tana delle Iene. This could be due either to the different environmental features of the two sites or to the high climatic variability that occurred during MIS3. [ABSTRACT FROM AUTHOR]

High-resolution marine palynological records from the northern South China Sea (SCS) provide new information concerning the regional history of vegetation and climate conditions during the last glaciation (~ 70–19 cal ka BP). The preservation of rich pollen from tropical and subtropical broadleaf trees (largely composed of evergreen Quercus , Castanopsis , and Euphorbiaceae) suggests that a southern subtropical climate prevailed during the last glaciation, including the period of the Last Glacial Maximum. Relatively higher percentages of such pollen taxa occurred during Marine Isotope Stage (MIS) 3, when Phyllocladus pollen from the south also increased, indicating a warmer terrestrial climate and a strengthened East Asian summer monsoon comparing to MIS 4 and 2. Moreover, the maximum percentages of such pollen occurred during the early MIS 3, implying that an optimal climate prevailed in this period. The reconstructed terrestrial climate corresponds well to marine evidence such as δ 18 O values from planktonic foraminifer shell and records of sea surface temperature. This study confirmed that the regional terrestrial climate could be linked closely to changes in both global ice volume and the East Asian monsoon attributable to variations of the earth’s orbital parameters. Modern palynological investigations and statistical analyses of the pollen percentages in the profiles indicate that Pinus pollen and spores are easily transported by water flow in the northern SCS. Therefore, their relative abundance peaks suggest that several wet intervals occurred during the last glaciation. [ABSTRACT FROM AUTHOR]

Abrupt, millennial-scale climate oscillations, known as Dansgaard–Oeschger (D–O) cycles, characterized the climate system of the last glacial period. Although proxy evidence shows that D–O cycles resulted in large-scale changes in atmospheric circulation patterns around the planet, an understanding of how Atlantic Meridional Overturning Circulation (AMOC) varied across these events remains unclear. Here, we take advantage of the fact that both tropical atmospheric circulation changes corresponding to north–south shifts in the Intertropical Convergence Zone (ITCZ) and large-scale changes in ocean circulation associated with AMOC variability can be reconstructed in the same sediment core from the Florida Straits to examine the relationship between atmospheric and ocean circulation changes across D–O events. To reconstruct surface water conditions, Mg/Ca-paleothermometry and stable isotope measurements were combined on the planktonic foraminifera Globigerinoides ruber (white variety) from sediment core KNR166-2 JPC26 (24°19.61′N, 83°15.14′W; 546 m depth) to reconstruct a high-resolution record of sea surface temperature and δ O seawater 18 (a proxy for upper mixed layer salinity) during Marine Isotope Stages (MIS) 2 and 3 from 20–35 ka BP. As an additional proxy for upper water column salinity change, we also generate a faunal abundance record of the salinity-sensitive planktonic foraminifera Neogloboquadrina dutertrei . Our results suggest that rapid reductions in sea surface salinity occurred at the onset of D–O interstadials, while stadials are characterized by increased surface salinities. The most likely cause of these salinity changes was variation in the strength and position of the ITCZ across D–O events. Finally, we examine the relationship between millennial-scale atmospheric circulation changes recorded in the planktonic records and ocean circulation changes inferred from the benthic δ O 18 record from our core. Our results provide some of the first evidence that AMOC strength did vary across at least one of the millennial-scale D–O cycles of MIS 3. [ABSTRACT FROM AUTHOR]

Sedimentological, palaeontological and mineralogical analyses of sediments from the endorheic Al Jafr Basin were conducted to better understand the depositional and hydrological conditions on the southern Jordan Plateau in the late Quaternary. Surficially exposed carbonate-rich sediments in the western part of the basin contain ostracod (micro-crustacean) shells of Ilyocypris cf. bradyi , Candona neglecta , Heterocypris salina , Fabaeformiscandona fabaeformis , Pseudocandona sp. and Herpetocypris brevicaudata . The shells of these and other more rare species, and charophyte and mollusc remains indicate that the sediments were formed in a wetland setting of shallow freshwater to slightly oligohaline ponds, streams and swamps. The present more northern distribution of some of the recorded taxa implies that climate conditions were probably cooler during the wetland formation. Radiocarbon age data for biogenic carbonate from two locations suggest that the wetland setting existed during the second half of Marine Isotope Stage (MIS) 3 or possibly earlier. A significantly higher water table must have existed in the basin during wetland formation; and wetter climate conditions are inferred for the catchment or at least for its highest and most humid westernmost part. Deflation and local sediment accumulation by wind and occasional sheet-wash events apparently prevailed in the region since MIS 2. Our newly presented data and inferences do not support the reconstruction of a previously reported large and relatively deep Pleistocene lake in the Al Jafr Basin. However, more extensive studies are certainly required for a detailed assessment of the Quaternary hydrological conditions in southern Jordan. [ABSTRACT FROM AUTHOR]

The Indonesian Throughflow (ITF) connects the western Pacific Ocean with the eastern Indian Ocean, thus forming one of the major near surface current systems of the global thermohaline circulation. The intensity of the ITF has been found to be sensitive to changes in global ocean circulation, fluctuations in sea level, as well as to the prevailing monsoonal conditions of the Indonesian Archipelago and NW Australia. This study presents the first reconstruction of ITF dynamics combining radiogenic isotope compositions of neodymium (Nd), strontium (Sr), and lead (Pb) of the clay-size detrital fraction to investigate changes in sediment provenance, and paleo seawater Nd signatures extracted from the planktonic foraminifera and authigenic Fe–Mn oxyhydroxide coatings of the marine sediments focussing on marine isotope stage 3 (MIS3). Sediment core MD01-2378 was recovered within the framework of the International Marine Global Change Study (IMAGES) and is located in the area of the ITF outflow in the western Timor Sea (Scott Plateau, 13° 04.95′ S and 121° 47.27′ E, 1783 m water depth). In order to produce reliable seawater signatures, several extraction methods were tested against each other. The results of the study show that at this core location the extraction of surface water Nd isotope compositions from planktonic foraminifera is complicated by incomplete removal of contributions from Fe–Mn oxyhydroxides carrying ambient bottom water signatures. The bottom water Nd isotope signatures reliably obtained from the sediment coatings (average εNd = −5.0) document an essentially invariable water mass composition similar to today throughout the entire MIS3. The radiogenic Nd, Sr, and Pb isotope records of the clay-sized detrital fraction suggest that the Indonesian Archipelago rather than NW Australia was the main particle source at the location of core MD01-2378, and thus indicating a persistently strong ITF during MIS3. Furthermore, the variations of the detrital radiogenic isotopes are shown to be more sensitive to changes in circulation and document a somewhat enhanced ITF intensity during the early part of MIS3 until 47.4 ka compared with the remaining MIS3. [ABSTRACT FROM AUTHOR]

This paper reports the fauna and distribution of large-sized benthic foraminifers ( LsBFs; defined as benthic foraminifers >0.5 mm in size) from surface sediments collected around Tahiti, French Polynesia, as well as from the Pleistocene deposits drilled off the Tiarei area, Tahiti, during Integrated Ocean Drilling Program ( IODP) Expedition 310. At least 6 and 22 genera of living and dead tests of LsBFs, respectively, were identified from modern surface sediments. Foraminiferal abundance in surface sediments depends mainly on the water depth and substratum type. The taxonomic composition of dead LsBF assemblages varies with depositional environments and water depths. Back-reef lagoon assemblages are dominated by Schlumbergerina alveoliniformis, whereas fore-reef slope and shelf assemblages are dominated by Amphistegina spp. The relative abundance of Amphistegina lessonii decreases with increasing water depth. On the shelf, A. lessonii is replaced by Amphistegina bicirculata and Planostegina sp. Pleistocene samples consisting mainly of volcaniclastic sandstone/siltstone and skeletal grainstone contained very small numbers and low species diversity of fossil LsBFs. Amphistegina lobifera, Heterostegina depressa, and Eponides repandus were commonly found in the Pleistocene samples. The taxonomic compositions showed little variation within holes. The Pleistocene assemblages were compositionally similar to those found in modern fore-reef slope environments of <30 m depth. Combined results of coral U/ Th ages and paleoenvironmental interpretations from in situ corals and LsBFs indicate that the Pleistocene sequence in the Tiarei area was deposited in a fore-reef slope environment during Marine Isotope Stage 3. [ABSTRACT FROM AUTHOR]