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Studying climate changes in the Eastern Mediterranean and Aegean region, particularly in Western Anatolia, is crucial for understanding environmental dynamics over time. We present high‐resolution, long‐term micro‐X‐ray fluorescence data from Buldan Yayla Lake (Denizli‐Buldan), a key area, covering the period from the Last Glacial Maximum (LGM) to the present. Sedimentological and paleoclimate data are supported by high‐resolution radiocarbon analyses, as well as two tephra chronologies from Cape Riva and Minoan. According to the results, a cold and arid climate is observed during the LGM, Post‐LGM and Younger Dryas. From the LGM to the present, there has been a trend towards increasing warmth and humidity. During the Late Glacial (LG) and Holocene (especially in the early Holocene), the climate was warmer and more humid. A short‐lived climate change associated with the Older Dryas is recorded during the Bølling–Allerød warm period (~13 200–12 350 cal a bp) within the LG. The data indicate that the sediment cores of Buldan Yayla Lake are highly sensitive in reflecting climate information between the LGM and the present day. At the same time, the climate in Western Anatolia is recorded as more stable throughout the Holocene. In conclusion, this study enhances our understanding of Western Anatolia's climate dynamics and environment–society relationship from the LGM to the present. [ABSTRACT FROM AUTHOR]

The Shyok Valley, within the Upper Indus Basin in Trans-Himalayas, lies in the cold and arid region. It is fed by the Siachen glacier; the largest glacier in the third pole. The fluctuations in this glacier are attributed to varying intensities of the two weather regimes namely mid-latitude westerlies and Southwest Monsoon. The reconstruction of the magnitude, timing, and landscape impact of glaciers in Nubra-Shyok valley have been explored in past decade yet they are contentious and uncertain. Therefore, the present study investigates the sediments from the key sites (Agham, Khardung, Changmar, Chalunka) in the Shyok valley using Optically Stimulated Luminescence (OSL) dating technique. The diverse geomorphology, including moraines, sand dunes, mass movement zone, alluvial fans are mapped to represent the geomorphic setting of the region. The chronological ages from the lower Shyok Valley (Agham section: 18.4 ± 2.2 ka) suggest extensive glacier expansion beyond the present terminus of the Siachen Glacier during the Marine Isotopic Stage (MIS)-2. The Khardung section has glaciofluvial deposits: 24.0 ± 2.4 ka (KHG-1), younger moraine: 8.2 ± 1.0 ka (KHG-9) and lacustrine deposits (KHGL-5, KHGL-6, KHGL-7): 14.1 ± 2.0 ka, 12.1 ± 1.1 ka, 10.7 ± 1.3 ka. The glacial events that occurred around 8.2 ka and 12.0 ka suggest glacial advancement which are likely due to a period of lower temperature. The Changmar section displays lacustrine deposits and debris flow events dated to the late glacial (14.5 ± 1.7 ka, CHG-1; 13.2 ± 1.6 ka, CHG-2) and deglaciation period (6.5 ± 1.2 ka, CHG-3; 5.5 ± 1.0 ka, CHG-4). The presence of the Holocene-aged lateral moraines (20 km away from Chalunka village: 14.3 ± 1.3 ka, CLM-2; 5.7 ± 0.9 ka, CLM-3; 0.4 ± 0.04 ka, CLM-4) and CHG-8: 2.1 ± 0.3 ka; outwash plain deposits: COP-7: 2.4 ± 0.4 ka aligns with the previous findings in the Nubra Valley, suggesting glacial advance in Little Ice Age in the whole valley. The glacial event occurring between 2.4 and 2.1 ka corresponds to the Neoglacial epoch, characterized by a glacial advance likely caused by a decrease in temperature during the late Holocene period. The intensified mid-latitude westerlies during MIS-2 are inferred to be the key factor in increased moisture to the Shyok Valley which led to the glacier expansion. These findings enhance our understanding of past climate changes in this high-altitude region and serve as a valuable baseline for future studies on glacial response to climate variations. [ABSTRACT FROM AUTHOR]

Stable water isotopes in inland Antarctic ice cores are powerful paleoclimate proxies; however, their relationship with dynamical atmospheric circulations remains controversial. Using a water isotope climate model (MIROC5‐iso), we assessed the influence of the Last Glacial Maximum (LGM; ∼21,000 years ago) sea surface temperatures (SST) and sea ice (SIC) on Antarctic precipitation isotopes (δ18Op) through atmospheric circulation. The results revealed that the synoptic circulation mostly maintained southward moisture transport, reaching inland Antarctica. The steepened meridional SST gradient in the mid‐latitudes increased δ18Op in inland Antarctica with the enhanced baroclinic instability and synoptic moisture transport. In contrast, expanded SIC distribution decreased δ18Op over Antarctica by enhanced preferential removal of heavy isotopes during vapor transport due to the increased transport distance and enhanced surface cooling. These findings propose to use Antarctic ice cores to describe the southern hemisphere atmospheric circulation, represented by the westerly jets, during the LGM and other past climates. Plain Language Summary: Stable water isotopes are widely used to reconstruct past variations of Earth's climate, such as the temperature in Antarctica during the Last Glacial Maximum (LGM) ∼21,000 years ago. This is an essential period for the climate community, given the order of magnitude of the temperature change between the LGM and today, which is similar to that of today's warming. However, the relationship between stable water isotopes and temperature is still subject to debate because of the influence of other climatic factors. Using an isotope‐enabled climate model, we found that the isotopic composition of Antarctic precipitation was not simply associated with the high and low average Antarctic temperature, but was substantially influenced by changes in dynamical atmospheric circulation related to sea surface temperature and sea ice expansion. We also suggest that representation of the past atmospheric circulations, such as westerly jets, can be constrained using water isotopic signals in Antarctic ice cores. Key Points: Synoptic circulations sustained the moisture transport toward inland AntarcticaMeridional sea surface temperature gradient enhanced moisture and heavy isotope precipitations on Antarctica, unlike sea ice expansionAntarctic ice core isotopes may refine southern hemisphere atmospheric circulations during the last glacial maximum [ABSTRACT FROM AUTHOR]

There are few studies on the climate and glacial scale in the mountains east of the Qinghai–Tibet Plateau. So, we used glacial features to determine the range of the area's paleoglaciers and the equilibrium line altitude (ELA) of theGlA modern and paleoglaciers in the Tianchi area of the Changbai Mountains. Then, the GlaRe toolbox 2015 () was used to reconstruct the surface of the paleoglaciers. The probable air temperature during the glacial advances of the LGM was calculated by applying the P-T and LR models. The results showed the following: (1) the change in ELA is 950 m in the Tianchi area of the Changbai Mountains; (2) glacial coverage in the Tianchi area of the Changbai Mountains during the LGM period was ~27.05 km2 and the glacial volume was ~9.94 km3; and (3) the mean temperature in the Tianchi area of the Changbai Mountains during the LGM was 6.6–9.0 °C lower than today's, and was the principal factor controlling the growth of glaciers. There is a difference in the climate change in monsoon-influenced mountains during the LGM, and this difference may be related to the precipitation in the mountains. [ABSTRACT FROM AUTHOR]

The Lac Fallère area in the upper Clusellaz Valley (tributary of the middle Aosta Valley) is shaped in micaschist and gneiss (Mont Fort Unit, Middle Penninic) and in calcschist and marble (Aouilletta Unit, Combin Zone). Lac Fallère exhibits an elongated shape and is hosted in a WSW–ENE-trending depression, according to the slope direction. This lake also shows a semi-submerged WSW–ENE rocky ridge that longitudinally divides the lake. This evidence, in addition to the extremely fractured rocks, indicates a wide, deep-seated gravitational slope deformation (DSGSD), even if this area is not yet included within the regional landslide inventory of the Aosta Valley Region. The Lac Fallère area also shows reliefs involved in glacial erosion (roches moutonnée), an extensive cover of subglacial sediments, and many moraines essentially referred to as Lateglacial. The DSGSD evolution in a glacial environment produced, as observed in other areas, effects on the facies of Quaternary sediments and the formation of a lot of wide moraines. Glacial slope sectors and lateral moraines displaced by minor scarps and counterscarps, and glaciers using trenches forming several arched moraines, suggest an interplay between glacial and gravitational processes, which share part of their evolution history. [ABSTRACT FROM AUTHOR]

Avulsion of rivers can be a gradual process that is associated with a metamorphosis of channel pattern or changed channel characteristics. The processes controlling avulsion, and hence anastomosis, often operate too slowly to study by measuring active river systems, and hence well preserved Late Quaternary rivers offer one of the best ways to study the long‐term development of avulsive systems. The modern and ancient channels of the Murrumbidgee River provide a classic example of long‐lived, semi‐static anastomosis, operating on timescales that include stadial and interstadial climate cycles. Over the last glacial cycle, regional avulsions have occurred every ~12 ka while maintaining an anastomosing pattern through the slow infill of abandoned channels. The Yanco Creek Palaeochannel System emerged from a period of high discharge linked to snowmelt in the terminal Pleistocene. Here, geomorphological mapping of the Yanco System was conducted together with single‐grain, optically stimulated luminescence dating of sediments in the channel belt. Since the main phase of channel construction during the Last Glacial Maximum, the Yanco system has functioned as a flood conduit and minor anabranch of the Murrumbidgee River, with reworking of ancient channel sediments by an underfit stream that is ongoing to the present day. Our new ages of ~13–14 ka are interpreted as channel sedimentation during an underfit phase following avulsion. The prevalence of full and partial avulsion in this environment may be complicating palaeohydrological interpretations of ages for channel activity, and reworking has gone unrecognised. We contend that some previous interpretations of the significance of ages for sediments collected from palaeochannels in the Riverine Plain may need revision. [ABSTRACT FROM AUTHOR]

The Lac Fallère area in the upper Clusellaz Valley (tributary of the middle Aosta Valley) is shaped in micaschist and gneiss (Mont Fort Unit, Middle Penninic) and in calcschist and marble (Aouilletta Unit, Combin Zone). Lac Fallère exhibits an elongated shape and is hosted in a WSW–ENE-trending depression, according to the slope direction. This lake also shows a semi-submerged WSW–ENE rocky ridge that longitudinally divides the lake. This evidence, in addition to the extremely fractured rocks, indicates a wide, deep-seated gravitational slope deformation (DSGSD), even if this area is not yet included within the regional landslide inventory of the Aosta Valley Region. The Lac Fallère area also shows reliefs involved in glacial erosion (roches moutonnée), an extensive cover of subglacial sediments, and many moraines essentially referred to as Lateglacial. The DSGSD evolution in a glacial environment produced, as observed in other areas, effects on the facies of Quaternary sediments and the formation of a lot of wide moraines. Glacial slope sectors and lateral moraines displaced by minor scarps and counterscarps, and glaciers using trenches forming several arched moraines, suggest an interplay between glacial and gravitational processes, which share part of their evolution history.

Abstract Stable water isotopes in inland Antarctic ice cores are powerful paleoclimate proxies; however, their relationship with dynamical atmospheric circulations remains controversial. Using a water isotope climate model (MIROC5‐iso), we assessed the influence of the Last Glacial Maximum (LGM; ∼21,000 years ago) sea surface temperatures (SST) and sea ice (SIC) on Antarctic precipitation isotopes (δ18Op) through atmospheric circulation. The results revealed that the synoptic circulation mostly maintained southward moisture transport, reaching inland Antarctica. The steepened meridional SST gradient in the mid‐latitudes increased δ18Op in inland Antarctica with the enhanced baroclinic instability and synoptic moisture transport. In contrast, expanded SIC distribution decreased δ18Op over Antarctica by enhanced preferential removal of heavy isotopes during vapor transport due to the increased transport distance and enhanced surface cooling. These findings propose to use Antarctic ice cores to describe the southern hemisphere atmospheric circulation, represented by the westerly jets, during the LGM and other past climates.

Reconstructing the extent and timing of palaeoglaciers and their associated climate is of great importance for understanding the responses of glaciers to climate change. Glacial landforms are well-preserved in Zheduo Shan, one of the high mountain ranges on the eastern Tibetan Plateau (TP). However, few studies have constrained glacial chronologies and estimated palaeoclimate in this area. We investigated the glacial advance during the Last Glacial Maximum (LGM) in Zheduo Shan using 10Be surface exposure dating. We then reconstructed the extent and thickness of LGM glaciers based on geomorphological mapping and a flowline-based glacial model-PalaeoIce. Eleven 10Be exposure ages confirmed a major LGM glacial advance between 20.0 ± 3.2 ka and 19.3 ± 2.8 ka. The reconstructed LGM glaciers in this mountain range covered an area of 499.16 km2 with an average ice thickness of 54.4 m and a total ice volume of 52.82 km3. The regional average equilibrium-line altitude (ELA) was estimated as 4524 ± 140 m, 535 ± 140 m lower than the present value. Based on the empirical relationship between precipitation and temperature (P-T model) at the ELAs on the TP, the temperature and precipitation were estimated as 3.10–5.27 °C and 10–16% lower during the LGM than the present values, respectively. These results suggest that the LGM glacial advance was more sensitive to temperature than precipitation in Zheduo Shan. [ABSTRACT FROM AUTHOR]

Excavation campaigns conducted at the Pécel‐Kis hársas site (Hungary) between 2014 and 2017 yielded the remains of a mature female woolly rhinoceros (Coelodonta antiquitatis) and six lithic artefacts. Radiocarbon dating confirmed that the rhinoceros died ca. 20.4k cal a bp, at the very end of the Last Glacial Maximum and, considering the position of the artefacts when found, it was probably killed by Epigravettian hunters. Based on dental analyses of the specimen, a vigorous lichen‐ (and possibly moss‐)consuming diet could be inferred for the end of the animal's lifetime. Based on Sr results, we can exclude the possibility of long‐range migration. In accordance with the optimum environmental demands of the foraging lichen, the low δ18O value of osseous material implies a relatively cold contemporaneous climate with a calculated mean annual air temperature of around 0.7 °C. Meanwhile, the extremely low δ15N value may have resulted from the proximity of the discontinuous permafrost zone and some intensive soil dislocation. Consequently, poor vegetation and an open, tundra‐like habitat can be assumed to have been dominant at the site at that time, which is also supported by palaeoenvironmental modeling experiments. [ABSTRACT FROM AUTHOR]

There is a great controversy regarding the cooling magnitude and the existence of ancient glaciers during the Last Glacial Maximum (LGM) in the east of China. The cooling magnitude during the LGM can be seen as a basis for determining whether glaciers developed during the Quaternary. In this study, we chose 9 mountain areas where there are long-term meteorological records as the research sites. And there are different glacier-climate conditions at these 9 sites. The degree-day model was conducted to estimate the snow mass and the snowmelt at the altitude of the bottom of ancient cirques (snow line) based on the mean multiple-year-day temperature and mean multiple-year-day precipitation. The results showed that: (1) The altitude of the modern snow line of Tianshan Mountains was similar to the result estimated by the degree-day model, which indicated this model can be used to determine the altitude of ancient cirques, and it can also be used to calculate the cooling magnitude required to meet a condition for cirques to develop at a given altitude. (2) For the sites where ancient cirques existed in the monsoon zone, the cooling magnitude during the LGM was 6.4 °C, 6.4 °C, and 8.0 °C in Garze, Taibi Mountain, and Yu Mountain, respectively. For the site where ancient cirques existed in the non-monsoon zone, the cooling magnitude during the LGM was 3.3 °C in Tianshan Mountains. The mean cooling magnitude during the LGM was 5.9 °C in China. (3) A much greater cooling magnitude was required to develop cirques during the LGM than the average cooling magnitude of China in Huanggangliang, Wutai Mountain, Tai Mountain, Shenlongjia, and Lu Mountain. (4) The cooling magnitude was underestimated by the TraCE-21ka model compared with this study. The differences between the results from the TraCE-21ka model and this study were approximately 3.3 °C, 2.9 °C, and 5.7 °C for Garze, Taibai, and Yu Mountain, respectively, averaging 4.0 °C. (5) There was no sufficient evidence showing that the cooling magnitude during the LGM decreased with latitude. [ABSTRACT FROM AUTHOR]

This research focuses on species distribution modelling (SDM) to have an idea of distribution of Anatolian spiny mouse, Acomys cilicicus in the Last Glacial Maximum (LGM), the mid-Holocene and present by using coordinates along Silifke which is the only location the species found. Three ensembled species distribution models (generalized additive mod-els, maximum entropy and boosted regression trees) were used to project Anatolian spiny mouse environmental suitability. Results indicate that current distribution of A. cilicicus populations shifted east to west since during the Last Glacial Maximum and apparently eastern part of the Mediterranean region of Turkey is potential refugia for this species.

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This study outlines the paleoglacial history and paleoclimatic conditions that were present during the Last Glacial Maximum (LGM) and Lateglacial (LG) in the Songlong and Zhuxi valleys in the eastern Nyainqêntanglha Range, southeastern Tibet. Two sets of moraines were identified at the valley mouths, and were dated using cosmogenic 10Be exposure and optically stimulated luminescence (OSL) dating. The ages suggest that two glaciations occurred at ~20–21 and ~14–16 ka, respectively, coinciding with the LGM and LG. Using glacier–climate modeling, temperature drops were calculated to have ranged from 6.3 to 7.8 °C during the LGM–LG, with precipitation being 40–60% of the present‐day value. The results in the modeled domain appear generally consistent with other climatic records from the Tibetan Plateau. Glacial advances in monsoon‐dominated southeastern Tibet during the LGM–LG were probably driven by low temperatures rather than by high precipitation, which was usually produced by an enhanced Indian Summer Monsoon during periods of climatic warming. [ABSTRACT FROM AUTHOR]

The impacts of climate change on the relationship between fluvial processes and dune landform evolution have been studied. However, the chronology data used to examine this relationship are deficient. The Keriya River has a glacial origin in the Kunlun Mountains on the south margin of the Tarim Basin. The river flows into the Taklimakan Desert, the second largest shifting-dune desert in the world. The dry channels and shifting dunes in this area provide an ideal opportunity to investigate fluvial and aeolian landform evolution processes and their relationship with climate change. We investigated this area during 2008–2011 and obtained 18 fluvial sediment samples from 16 sections for optically stimulated luminescence (OSL) dating. The results show that the ages ranged from 3.4–44.1 ka. Most of the samples (13) were Holocene in age, around 11 ka, 8–9 ka, 5–6.5 ka, 4.6 ka, and 3.4–3.7 ka and were distributed along ancient river channels around sites of Yuansha and Karadun. Two samples close to the Hotan River (38–47 ka) fall within the Marine Isotope Stage 3 (MIS3). Three samples (from one section) were located near ancient channels flowing towards the Yuansha Site and had ages of around 14.5 ka, i.e., during the Last Glacial Maximum (LGM). The analyses of the sediment samples and OSL ages suggest that the Keriya River flooded in the Holocene, the LGM, and MIS3. Fluvial sediments provided the source material for the dunes, and fluvial processes affected the landform evolution in the lower Keriya River. Our results suggest that most of the dunes covered in fluvial sediments in the lower reaches and the area west of the Keriya River developed since the Holocene. This differs from the results of previous studies, which suggested that they developed since the Han (202BC–220AD) and Tang (618–907AD) dynasties. The OSL ages of the fluvial sediments are consistent with the reported deglaciation (after glacial advance) ages in the alpine mountains surrounding the Tarim Basin. This suggests that climate fluctuations may have affected the occurrence of floods and the formation of dunes in the Taklimakan Desert. [ABSTRACT FROM AUTHOR]

There are few studies on the climate and glacial scale in the mountains east of the Qinghai–Tibet Plateau. So, we used glacial features to determine the range of the area’s paleoglaciers and the equilibrium line altitude (ELA) of theGlA modern and paleoglaciers in the Tianchi area of the Changbai Mountains. Then, the GlaRe toolbox 2015 () was used to reconstruct the surface of the paleoglaciers. The probable air temperature during the glacial advances of the LGM was calculated by applying the P-T and LR models. The results showed the following: (1) the change in ELA is 950 m in the Tianchi area of the Changbai Mountains; (2) glacial coverage in the Tianchi area of the Changbai Mountains during the LGM period was ~27.05 km2 and the glacial volume was ~9.94 km3; and (3) the mean temperature in the Tianchi area of the Changbai Mountains during the LGM was 6.6–9.0 °C lower than today’s, and was the principal factor controlling the growth of glaciers. There is a difference in the climate change in monsoon-influenced mountains during the LGM, and this difference may be related to the precipitation in the mountains.

Since the last glacial period, North America has experienced dramatic changes in regional climate, including the collapse of ice sheets and changes in precipitation. We use clumped isotope (∆47) thermometry and carbonate δ18O measurements of glacial and deglacial pedogenic carbonates from the Palouse Loess to provide constraints on hydroclimate changes in the Pacific Northwest. We also employ analysis of climate model simulations to help us further provide constraints on the hydroclimate changes in the Pacific Northwest. The coldest clumped isotope soil temperatures T(∆ ${\increment}$47) (13.5 ± 1.9°C to 17.1 ± 1.7°C) occurred ∼34,000–23,000 years ago. Using a soil‐to‐air temperature transfer function, we estimate Last Glacial Maximum (LGM) mean annual air temperatures of ∼−5.5°C and warmest average monthly temperatures (i.e., mean summer air temperatures) of ∼4.4°C. These data indicate a regional warming of 16.4 ± 2.6°C from the LGM to the modern temperatures of 10.9°C, which was about 2.5–3 times the global average. Proxy data provide locality constraints on the boundary of the cooler anticyclone induced by LGM ice sheets, and the warmer cyclone in the Eastern Pacific Ocean. Climate model analysis suggests regional amplification of temperature anomalies is due to the proximal location of the study area to the Laurentide Ice Sheet margin and the impact of the glacial anticyclone on the region, as well as local albedo. Isotope‐enabled model experiments indicate variations in water δ18O largely reflect atmospheric circulation changes and enhanced rainout upstream that brings more depleted vapor to the region during the LGM. Plain Language Summary: Warming and water isotope variations inferred from clumped isotopes are similar to transient climate model simulations for the Pacific Northwest from the Last Glacial Maximum to present. The amount of warming was larger than the global average and is likely due to the proximity of the site to the glacial margin. Key Points: Clumped isotopes reveal changes in temperature and water isotopes over the past 36,000 years consistent with transient model simulationsWarming since the LGM was 16.4 ± 2.6°C, 2.5–3x the global average, likely due to proximity of site to ice marginModel analysis indicates δ18O depletion in this location at the LGM is largely a result of the North American ice sheets [ABSTRACT FROM AUTHOR]

Abstract The current distributions of organisms have been shaped by both current and past geographical barriers. However, it remains unclear how past geographical factors—currently cryptic on the sea floor—affected the current distributions of terrestrial animals. Here, we examined the effects of currently cryptic ancient rivers on current genetic differentiation of the large Japanese wood mouse, Apodemus speciosus, which inhabits islands in the Seto Inland Sea, Japan. Genome-wide polymorphisms were identified by GRAS-Di (Genotyping by Random Amplicon Sequencing, Direct) analysis of 92 A. speciosus individuals. Maximum-likelihood analysis was performed with 94,142 single nucleotide polymorphisms (SNPs) identified by GRAS-Di analyses. Ancient rivers were visualized by Geographic Information System (GIS) channel analysis. Maximum-likelihood analysis showed strong support for the monophyly of each population in the islands in the Seto Inland Sea; it also showed close relationships between Innoshima-Ikuchijima, Ohmishima-Hakatajima-Oshima, Ohmishima-Hakatajima, Ohsakikamijima-Ohsakishimojima, Kamikamagarijima-Shimokamagarijima, and Kurahashijima-Etajima islands. The principal component analyses of the SNPs also supported these relationships. Furthermore, individuals from islands located on the east and west sides of the main stream of the ancient river were clustered on each side with strong support. These phylogenetic relationships were completely congruent with the paleogeographic relationships inferred from ancient rivers. In conclusion, the findings demonstrated that the current distribution of genetically distinct island lineages was shaped by ancient rivers that are currently submerged beneath the Seto Inland Sea, Japan.

Understanding past long-term vegetation responses to regional or even global climate change and forcing mechanisms is essential to future climate change projections. However, due to the lack of long-term terrestrial sedimentary records, there are few studies focusing on vegetation changes in tropical southern China since the last glacial period, especially from the perspective of peat n -alkane records. Here, we have presented a peat core record from the Xialu peatland in the northern Leizhou Peninsula, and n -alkanes were investigated in conjunction with multiple proxy indicators. Our results showed that the organic matter sources were mainly a mixture of aquatic and terrestrial vegetation, with terrestrial vegetation accounting for most of the bulk organic matter composition. From ∼44.1 to 29 cal kyr BP, the organic matter source was mainly dominated by terrestrial vegetation, which corresponds to warm and humid conditions. From 29 to 14 cal kyr BP, the input of the terrestrial vegetation was reduced, the aquatic vegetation input increased, implying cool and dry conditions. From 14 to 9.3 cal kyr BP, the climate gradually became warmer and wetter, and terrestrial vegetation dominated in this area. Overall, the climatic conditions from the Xialu peatland were generally consistent with other records from adjacent areas. Our results suggest that, during the Last Glacial Maximum (LGM), a substantial drop in regional and global sea levels may have been the main cause of drought in tropical southern China on orbital timescales. Meanwhile, several climatic fluctuations on millennial timescales could have been influenced by the variability of the North Atlantic Meridional Overturning Circulation (AMOC) and migration of the Intertropical Convergence Zone (ITCZ). [Display omitted] • n -alkanes were investigated together with multiple proxy indicators. • Terrestrial vegetation accounted for most of the bulk organic matter. • Vegetation changes are mainly regulated by sea level change on orbital timescales. • AMOC and ITCZ affect vegetation and environmental changes on millennial timescales. [ABSTRACT FROM AUTHOR]

This study examines the isotopic potential of mammoth remains from three paleontological sites in the southeast of the West Siberian Plain (SEWS): Shestakovo, Krasnoyarskaya Kurya, and Volchia Griva. We analysed oxygen isotopes from 29 mammoth enamel and tusk samples and horse and deer enamel samples. We verified sample preservation using ATR-FTIR and obtained δ18Op, δ18Oc, and reconstructed δ18Ow values for 28-22 ka cal BP. Preservation assessments revealed variable preservation conditions. Our findings indicate an increase of 1.4‰ in reconstructed δ18Ow values from glacial levels at 28-23 ka to late-glacial conditions at ca. 17–15.5 ka, likely reflecting climatic warming at the end of the Pleistocene. The extensive fossil material at these sites offers significant potential for further Last Glacial Maximum studies. • We analysed 29 mammoth, deer and horse enamel samples from 3 paleontological sites in Western Siberia. • Preservation of the samples was assessed using ATR-FTIR and oxygen isotope CO3-PO4 equilibrium. • Increase in δ18O values of meteoric waters from 28-23 to 24-22 ka cal BP is attributed to temporal climate development. • Gradient of δ18O depletion between SEWS and Europe suggests similar "continental effects" during the LGM and present day. • SEWS had more pronounced climatic changes than the European plain, transitioning from glacial to lateglacial. [ABSTRACT FROM AUTHOR]

The extent of glaciers in the western French Alps foreland during the last glacial maximum (LGM, 26.5-19 ka) has not yet been determined, so understanding glacial paleogeography during the LGM remains an open question. This study focuses on the glacial chronology in the western French Alps piedmont using 10Be surface exposure ages on nine glacial boulders and 12 erratic boulders. Results indicate an LGM glacier advance between ca. 24 and 21 ka. During the late LGM, a smaller glacier readvance or stabilization phase occurred at ca. 19 ka, which was followed by a withdrawal phase between ca. 19 and 16.5 ka. Our outcomes show that the LGM extent in the western French Alps was similar or slightly less extensive than the pre-LGM ice extents during the last glacial. Such paleogeography has also been suggested in the western Italian Alps, which share the same accumulation zone with the western French Alps glaciers. The LGM dynamic of the western French Alps foreland glaciers highlighted by our exposure ages is consistent with the timing of the LGM glacier advances and deglaciation with the western Italian ice lobes. [ABSTRACT FROM AUTHOR]

This research focuses on species distribution modelling (SDM) to have an idea of distribution of Anatolian spiny mouse, Acomys cilicicus in the Last Glacial Maximum (LGM), the mid-Holocene and present by using coordinates along Silifke which is the only location the species found. Three ensembled species distribution models (generalized additive models, maximum entropy and boosted regression trees) were used to project Anatolian spiny mouse environmental suitability. Results indicate that current distribution of A. cilicicus populations shifted east to west since during the Last Glacial Maximum and apparently eastern part of the Mediterranean region of Turkey is potential refugia for this species. [ABSTRACT FROM AUTHOR]

Paleoclimatic constraints from mountain ranges separating major climate systems are important in understanding past climatic changes. Using the present-day glacial geomorphology combined with the GlaRe model, the last glacial maximum (LGM) of seven representative valley glaciers of the Pir Panjal Range (PPR), Kashmir Himalaya was reconstructed. The Range lies at the interface of the tropical and temperate climates in the NW Himalayas. The glacier reconstructions showed that the glaciers in the Range advanced ~10 km down the present-day cirque margins and attained a thickness of more than 200 m during the LGM. Using six different methods, the equilibrium line altitude (ELA) changes in the selected valleys of the PPR were estimated for which the LGM was reconstructed. ELA depressions calculated for the LGM vary from 374 m to 416 m with a mean of 395 m. The weighted average ELA of the Range lies at an altitude of 3922 m a.s.l showing a general increasing trend from SE to NW of the Range. The published chronology of the loess deposits, a proxy for glacial aridity, shows the evidence of significant glacial advances starting around 350 kya in the valley, which is consistent with the evidence of both the pre- and post-LGM advances observed in this study. The presence of extensive glacier features all across the PPR and the presence of a few small heavily debris-covered glaciers in the Range points towards the rapid deglaciation in the area. [ABSTRACT FROM AUTHOR]

Although Last Glacial Maximum (LGM) sea levels have been the focus of much attention in climate and marine sciences, the timing, duration, and magnitude need further research. Here we present observations and analyses of the deepest speleothems (-116 m) collected from the deepest known blue hole on a global scale, the Sansha Yongle Blue Hole, Xisha Islands, South China Sea. The field investigations illustrate that submerged speleothems are irregular cauliflower-like coatings on the downward cave ceiling from water depths of ~90 to 120 m. The downward growth direction and negative stable carbon and oxygen stable isotopes of submerged speleothems suggest that they may deposit in an air-filled condition through gravity drip, indicating the maximum LGM sea level. The deep submerged speleothems were dated, indicating two U–Th ages of 29.16 ± 0.17 and 26.04 ± 0.18 ka BP and one radiocarbon age of 18.64 ± 0.12 ka BP, respectively. The investigated deep submerged speleothems therefore clearly determine the minimum onset and maximum termination times for LGM terms of sea level. The results show that LGM began at ~29 ka BP and ended at ~18.5 ka BP. This study therefore provides initial evidence for the use of deep speleothems to determine LGM sea levels and emphasizes the importance of deep submerged speleothems in the reconstruction of Pleistocene low sea levels.

Palaeoglacier modelling is an important approach for reconstructing the palaeoclimate. The timing of glaciations in the central part of the Gangdise Mountains has been constrained previously, but the palaeoclimate remains unclear. In this paper, the palaeo-temperature and precipitation of the early marine isotope stage (MIS) 2, the Last Glacial Maximum (LGM), and the early Holocene were reconstructed using coupled mass balance and ice flow models. The results show that a series of temperature changes (ΔT) and precipitation factors (Fp) resulted in optimum palaeoglacial extents. The modelled palaeoglaciers during the early MIS 2, the LGM, and the early Holocene cover areas of ~18.1 km2, ~17.4 km2, and ~16.3 km2, respectively, with ice volumes of ~2.18 km3, ~1.99 km3, and ~1.95 km3, respectively. Previous studies on ice cores, pollen samples, and lake sediments were referenced to narrow the range of palaeo-temperatures and precipitations. The reconstructed temperatures during the early MIS 2, LGM, and early Holocene were constrained to 2.4–2.9 °C, 2.15–3.05 °C, and 0.95–1.5 °C lower than today, respectively. Their precipitation levels were 60–80%, 50–80%, and 100–150% of the present-day level, respectively. [ABSTRACT FROM AUTHOR]

In tectonically active mountain ranges, the landscape is shaped by the interplay of erosion/sedimentation and tectonically driven crustal deformation. Characteristic landforms such as moraines, wind gaps, fault scarps, and river terraces can be used to decipher the landscape evolution. However, the available data often allow for different interpretations. Here we study the Pradol (Pradolino) Valley in Western Slovenia, a deeply incised canyon whose floor rests several hundreds of metres above the surrounding valleys. We use high-resolution digital elevation models, geomorphic indices and field observations to unravel the evolution of this peculiar landform. We present a six-stage evolution model of the canyon that includes the blockage of valleys by advancing glaciers, river diversion, and rapid incision due to a high discharge of post-glacial meltwater. The formation of the Pradol Valley was most likely facilitated by an underlying fault that serves as an easily erodible weakness zone in the Mesozoic limestones. Our model indicates that the formation of the canyon could have occurred during the last glaciation, which results in incision rates of several cm/yr. With the proposed model we can explain all remote and field observations available. Our study shows that a complex interplay of different landscape-shaping processes is needed to explain the occurrence of the Pradol dry valley and that rapid changes in the morphology occurred after the last glacial maximum.

The glaciated island of South Georgia in the sub-Antarctic is a key area for climate reconstructions, because it is positioned in the Southern Ocean amidst the core belt of the Southern Westerlies and the main fronts of the Antarctic Circumpolar Current. This makes it particularly susceptible to changes in local, regional, but also Southern Hemisphere-wide climate conditions. Marine-geological records recovered from its continental shelf therefore offer unique potential to constrain how ice masses in this part of the Southern Ocean responded to Quaternary climate change, but despite this, little glacial-geomorphological and sedimentological research has been done offshore South Georgia. Here, we present a new suite of glacial landforms, identified from high-resolution bathymetry data, supplemented with acoustic facies from sub-bottom profiles, in order to reconstruct the pre-Holocene glacial history of the King Haakon Trough System on the southwestern South Georgia continental shelf. Our data show numerous landforms common for phases of ice advance and retreat, which are interpreted to document the confluence of two major trunk glaciers during peak glaciation. Progressively elongated linear bedforms imply accelerated ice flow and/or softer sediment substrate towards the shelf edge and suggest that the South Georgia Ice Cap experienced streaming ice and behaved similarly to other palaeo-ice sheets. A grounding-zone wedge close to the shelf edge marks the position of maximum ice extent during a peak glaciation, while clusters of recessional moraines and three large morainal banks indicate repeated phases of staggered retreat. Multiple extensive ice advances are indicated by stacked till sequences within the sub-bottom profiles of the mid- and outer shelf. The second-to-last till generation appears to be slightly more extensive than the most recent glacial till, and could suggest that South Georgia may have had a similar glacial evolution to other sub-Antarctic islands. This paper complements two studies focusing on the Holocene depositional environments and their associated sedimentary processes in the same trough system, in an effort to elucidate an important part of the Quaternary evolution of South Georgia's marine environment. • King Haakon Trough System formed over the course of several glaciations. • Glacial landforms on the modern seafloor show evidence of fast advance and staggered retreat. • Ice stream draining South Georgia Ice Cap during LLGM configured as ice-cliff margin. • Stacked till sequences attest to multiple ice advances to the shelf edge. [ABSTRACT FROM AUTHOR]

The current distributions of organisms have been shaped by both current and past geographical barriers. However, it remains unclear how past geographical factors—currently cryptic on the sea floor—affected the current distributions of terrestrial animals. Here, we examined the effects of currently cryptic ancient rivers on current genetic differentiation of the large Japanese wood mouse, Apodemus speciosus, which inhabits islands in the Seto Inland Sea, Japan. Genome-wide polymorphisms were identified by GRAS-Di (Genotyping by Random Amplicon Sequencing, Direct) analysis of 92 A. speciosus individuals. Maximum-likelihood analysis was performed with 94,142 single nucleotide polymorphisms (SNPs) identified by GRAS-Di analyses. Ancient rivers were visualized by Geographic Information System (GIS) channel analysis. Maximum-likelihood analysis showed strong support for the monophyly of each population in the islands in the Seto Inland Sea; it also showed close relationships between Innoshima-Ikuchijima, Ohmishima-Hakatajima-Oshima, Ohmishima-Hakatajima, Ohsakikamijima-Ohsakishimojima, Kamikamagarijima-Shimokamagarijima, and Kurahashijima-Etajima islands. The principal component analyses of the SNPs also supported these relationships. Furthermore, individuals from islands located on the east and west sides of the main stream of the ancient river were clustered on each side with strong support. These phylogenetic relationships were completely congruent with the paleogeographic relationships inferred from ancient rivers. In conclusion, the findings demonstrated that the current distribution of genetically distinct island lineages was shaped by ancient rivers that are currently submerged beneath the Seto Inland Sea, Japan. [ABSTRACT FROM AUTHOR]

Background Recently, the study of mitochondrial variability in ancient humans has allowed the definition of population dynamics that characterised Europe in the Late Pleistocene and Early Holocene. Despite the abundance of sites and skeletal remains few data are available for Italy. Aim We reconstructed the mitochondrial genomes of three Upper Palaeolithic individuals for some of the most important Italian archaeological contexts: Paglicci (South-Eastern Italy), San Teodoro (South-Western Italy) and Arene Candide (North-Western Italy) caves. Subjects and methods We explored the phylogenetic relationships of the three mitogenomes in the context of Western Eurasian ancient and modern variability. Results Paglicci 12 belongs to sub-haplogroup U8c, described in only two other Gravettian individuals; San Teodoro 2 harbours a U2'3'4'7'8'9 sequence, the only lineage found in Sicily during the Late Pleistocene and Early Holocene; Arene Candide 16 displays an ancestral U5b1 haplotype already detected in other Late Pleistocene hunter-gatherers from Central Europe. Conclusion Regional genetic continuity is highlighted in the Gravettian groups that succeeded in Paglicci. Data from one of the oldest human remains from Sicily reinforce the hypothesis that Epigravettian groups carrying U2'3'4'7'8'9 could be the first inhabitants of the island. The first pre-Neolithic mitogenome from North-Western Italy, sequenced here, shows more affinity with continental Europe than with the Italian peninsula.

Here we evaluate the hypothesis that during cold climatic phases, people and resources became increasingly packed along highland Lesotho's riverine corridors as the viability of palatable grasslands for large mammal hunting on the upland plateaus declined. These intensification efforts resulted in increased reliance on lower-ranked aquatic (fish) resources with knock-on effects for lithic technological organization. We compare data on the relative contribution of fishing to the diets of highland hunter-gatherers at Sehonghong rockshelter with a faunal proxy widely argued to correlate with subsistence intensification (faunal assemblage evenness). In addition, we compare these data with two measures of lithic technological intensification (cutting edge production and core reduction intensity) to test whether diet intensification tracks technological intensification. We show that at Sehonghong, aquatic resource exploitation is not always correlated with faunal assemblage evenness. We find that some layers (i.e. RF) show spikes in aquatic resource use irrespective of changes in faunal assemblage evenness. Other layers (i.e. RBL/CLBRF) were intensively occupied, but they do not have many fish. Our data also demonstrate that aquatic resource use is not correlated with lithic technological intensification. These results suggest that while aquatic resource exploitation was a 'fallback' option for some of Lesotho's highland hunter-gatherers, there is considerable variability. Our data show that multiple intensification dimensions were variably combined through the Late Pleistocene at Sehonghong as they were elsewhere in southern Africa. [ABSTRACT FROM AUTHOR]

Ntsikeni wetland is one of the largest high-altitude wetlands in southern Africa (~1795 m asl) located in the Swartberg area of the foothills of the Maloti-Drakensberg, southern Africa. The site has been designated a Ramsar Wetland of International Importance which, with limited anthropogenic influence, renders it ideal for palaeoenvironmental investigation. This study presents a pollen-derived palaeoenvironmental reconstruction for Ntsikeni, spanning the period ~25,100–650 cal BP, one of the longest, continuous records for southern Africa. The record commences with evidence of coldest conditions consistent with the peak of the Last Glacial Maximum. This is followed by progressive climatic amelioration, culminating in a warm, moist period from ~7500 to 5500 cal BP. Pronounced cold periods at ~13,500 cal BP, ~8500 cal BP and ~4000 cal BP are broadly consistent with coeval global scale temperature fluctuations. Two distinct dry events are inferred from the pollen record, spanning ~19,600–18,000 and ~6500-4900 cal BP. Wet events occur more frequently throughout the record, resulting in fluctuations in moisture availability, and are inferred to result in the expansion and contraction of the wetland extent similar to those recorded in the palaeorecords of the Lesotho Highlands. The Ntsikeni record provides a longer-term temporal framework with which the shorter sequences for adjacent sites in the Maloti-Drakensberg can be compared, and supports evidence for the significance of the rugged topography in inducing lags in moisture transitions. [ABSTRACT FROM AUTHOR]

Rambiara River basin, a sub-basin of the Upper Indus, is dotted with fluvial and glacial geomorphic landforms. The presence of large number of glacial landforms like moraines, cirques, aretes, U-shaped valleys, etc. reflects the enormous erosive power of the past glaciers. During the Last Glacial Maximum (LGM), glaciers on average were 200 m thick and extended more than 10 km from the present-day cirque marks. Rock glaciers outnumber the clean glaciers that cover an area of 0.22 and 1.25 km2, respectively, in the basin. Glacial lakes are the prominent features in the higher reaches of the basin and occupy an area ranging from 0.01 to 0.70 km2. Downstream, the river is characterized by large channel width, anomalous sinuosity, braided pattern, and the presence of unpaired fluvial terraces. The large channel width depicts the enormous discharge from the glacial- and snow-melt during the Late Pleistocene when glaciers covered most of the Pir Panjal. After LGM, the glacier cover and the river discharge significantly decreased as highlighted by a large number of braided bars and the narrow stream to which the river is reduced. The warming trends observed across the Himalayas encompassing the Pir Panjal Range since the last century has further contributed significantly to the glacier recession in the basin.

Characterising glaciological change within the tropical Andes is important because tropical glaciers are sensitive to climate change. Our understanding of glacier dynamics and how tropical glaciers respond to global climate perturbations is poorly constrained. Studies of past glaciation in the tropical Andes have focused on locations where glaciers are still present or recently vacated cirques at high elevations. Few studies focused on lower elevation localities because it was assumed glaciers did not exist or were not as extensive. We present the first geomorphological evidence for past glaciations of the Lagunas de Las Huaringas, northern Peru, at elevations of 3,900–2,600 m a.s.l. Mapping was conducted using remotely-sensed optical imagery and a newly created high-resolution (∼2.5 m) digital elevation model (DEM). The area has abundant evidence for glaciation, including moraines, glacial cirques, hummocky terrain, glacial lineations and ice-sculpted bedrock. Two potential models for glaciation are hypothesised: 1) plateau-fed ice cap, or 2) valley glaciation. Assuming glaciers reached their maximum extent during the Local Last Glacial Maximum (LLGM), between 23.5 ± 0.5 and 21.2 ± 0.8 ka, the maximum reconstructed glacial area was 75.6 km2. A mean equilibrium line altitude (ELA) of 3,422 ± 30 m was calculated, indicating an ELA change of −1,178 ± 10 m compared to modern snowline elevation. There is an east to west ELA elevation gradient, lower in the east and higher in the west, in-line with modern day transfer of moisture. Applying lapse rates between 5.5 and 7.5°C/km provides a LLGM temperature cooling of between 6.5–8.8°C compared to present. These values are comparable to upper estimates from other studies within the northern tropical Andes and from ice-core reconstructions. The mapping of glacial geomorphology within the Lagunas de las Huaringas, evidences, for the first time, extensive glaciation in a low elevation region of northern Peru, with implications for our understanding of past climate in the sub-tropics. Observations and reconstructions support a valley, rather than ice cap glaciation. Further work is required to constrain the timing of glaciations, with evidence of moraines younger than the LLGM up-valley of maximum glacier extents. Numerical modelling will also enable an understanding of the controls of glaciation within the region.

Abstract The Antarctic Intermediate Water (AAIW) is an essential global ocean water mass at intermediate depths. Coupled climate models in isotope‐enabled (δ18O, δD), fully coupled Community Earth System Model and Paleoclimate Model Intercomparison Project Phase 3 consistently show shallower AAIW depth at the Last Glacial Maximum (LGM) due to the northward shift of AAIW. More importantly, modeling results suggest that the northward shift of AAIW can be caused by sea ice expansion and the weakened hydrological cycle under the glacial climate. On the contrary, the AAIW under global warming tends to shift poleward compared to the pre‐industrial period driven by the retreating sea ice and strengthened hydrological cycle. However, the AAIW depth will shallow in response to the ongoing warming, likely due to the overwhelming effects of enhanced stratification and shallowing mixed layer.

The cold and warm intervals during the Plio‐Pleistocene provide an opportunity to assess the response of the Asian summer monsoon (ASM) to different levels of global warming. In this study, the northern edge of the ASM, a sensitive indicator of the advance and retreat of the ASM rain belt, was analyzed using climate outputs from PMIP3 and PlioMIP1, for the Last Glacial Maximum (LGM, ∼21,000 yr BP), the preindustrial, the mid‐Holocene (∼6,000 yr BP), and the mid‐Pliocene (∼3.3–3.0 Ma), among which the global temperature increased sequentially. The results show that the northern edge of the ASM migrated northwestward by ∼200 km, ∼50 km, and ∼50 km with global warming from the LGM to preindustrial, from the preindustrial to mid‐Holocene, and from the mid‐Holocene to mid‐Pliocene, respectively. These results are generally consistent with geological records. The simulations show that the western Pacific subtropical high (WPSH) intensified and expanded geographically, and the intertropical convergence zone (ITCZ) migrated northward over the Indian Ocean and was shifted southward over the western Pacific. This led to a northwestward shift of the Asian monsoonal rain belt, and consequently to wetter conditions in India and northern China. During the mid‐Pliocene, pronounced warming substantially intensified the WPSH, leading to the suppression of moisture transport from the Indian Ocean to southern China and the Indo‐China Peninsula. Our results suggest that if the planet returns to a Pliocene warm world, precipitation will increase in northern China, while southern China and the Indo‐China Peninsula will experience more frequent droughts. Key Points: Simulations show a warming‐induced northwestward shift of the Asian summer monsoon, which are consistent with geological recordsThe western Pacific subtropical high intensified and expanded in response to past global warmingThe intertropical convergence zone (ITCZ) moved north (south) over the Indian (West Pacific) Ocean in a warmer world [ABSTRACT FROM AUTHOR]

Until recently, several hypotheses on the origin(s) and dispersion of microblade technology in Northeast Asia have been presented and discussed. Although various definitions of microblade and bladelet have been proposed in diverse geographic and chronological contexts, several researchers may agree that the pressure knapping technique for microblade production plays a paramount role in the process of significant changes in lithic technology and human behaviours between marine isotope stages (MIS) 3 and 2. One of the main topics in the study of microblade technology in Northeast Asia is establishing a systematic and reliable method for identifying microblade knapping techniques that are quantitatively verified. This paper attempts to present a more improved method for identifying microblade knapping techniques by dealing with the analysis of fracture wings which are the reliable indicators of the crack velocity. The focus of this paper is on identifying obsidian microblade-like debitage knapping techniques in the Last Glacial Maximum (LGM) assemblage of Kawanishi-C in Hokkaido, Northern Japan. The results of fracture wing analysis show that the microblade-like longitudinal debitage production at the Kashiwadai-C site was employed by not pressure but percussion techniques. This gives new insights into the diversity of microblade and microblae-like debitage reduction sequences in the LGM Hokkaido and complex process of significant changes in lithic technology, especially in relation to the emergence of microblade technology. In addition, this study shows that the analysis of fracture wings can allow appropriate technological evaluation of the microblades and microblade-like longitudinal debitage production in the period before and around the LGM in Northeast Asia. [ABSTRACT FROM AUTHOR]

The Antarctic Intermediate Water (AAIW) is an essential global ocean water mass at intermediate depths. Coupled climate models in isotope‐enabled (δ18O, δD), fully coupled Community Earth System Model and Paleoclimate Model Intercomparison Project Phase 3 consistently show shallower AAIW depth at the Last Glacial Maximum (LGM) due to the northward shift of AAIW. More importantly, modeling results suggest that the northward shift of AAIW can be caused by sea ice expansion and the weakened hydrological cycle under the glacial climate. On the contrary, the AAIW under global warming tends to shift poleward compared to the pre‐industrial period driven by the retreating sea ice and strengthened hydrological cycle. However, the AAIW depth will shallow in response to the ongoing warming, likely due to the overwhelming effects of enhanced stratification and shallowing mixed layer. Plain Language Summary: The Antarctic Intermediate Water (AAIW) is an important component of global ocean circulation, and processes involved in AAIW variability have been extensively studied, particularly for its role in ventilating CO2 from deep oceans to the atmosphere during the last deglaciation. However, there is scarce information about changes in AAIW vertical extent and existing studies even seem to be controversial. In this study, modeling results consistently show a shallowing AAIW depth at the Last Glacial Maximum (LGM), mainly because of the equatorward shift of the entire AAIW. More importantly, we found that the northward shift of AAIW can be caused by the northward expansion of sea ice and the weakened hydrological cycle at the LGM. Under global warming conditions, the AAIW shifts poleward due to the retreating sea ice and strengthened hydrological cycle. However, the AAIW depth also shallows, likely due to overwhelming effects of enhanced stratification and shallower mixed layer. The results in this study are model‐based, and further studies, including more robust paleo observations, are needed to better understand the mechanisms that control the AAIW depth and extent. Key Points: The Antarctic Intermediate Water (AAIW) depth shallows due to the northward shift of AAIW at the Last Glacial Maximum (LGM)The northward shift of AAIW can be forced by sea ice expansion and the weakened hydrological cycle at the LGM [ABSTRACT FROM AUTHOR]

Temperate glaciers are very sensitive to changes in the global climate system and provide an excellent opportunity to obtain information on the timing and magnitude of palaeoclimatic changes. Numerous studies in the Mediterranean mountains indicate alternating glacial advance and retreat episodes during the last glacial cycle (110.8 ka to 11.7 ka ago). However, glacial chronology is often restricted to the global Last Glacial Maximum (LGM), and records covering the remainder of the last glacial cycle are less well-known in the eastern Mediterranean region. Here, we present a continuous chronology of glacial stages in the east Mediterranean based on cosmogenic 36Cl terrestrial cosmogenic nuclides (TCN) in glacial landforms. We present 105 36Cl ages (43 new and 62 recalculated from previously published studies) from the moraine, landslide, glacial outwash boulders, and limestone bedrock from Mt. Aladağlar (37°8′N, 35°2′E) in the central Taurus Mountains of Southern Türkiye. Three local icefields (Yedigöller, Körmenlik, and Akçay icefields, covering 20 km2, 8 km2, and 7 km2, respectively, and >3000 m above sea level (asl)) occupied the summits in the past. The bedrock ages obtained from the uppermost parts of the Yedigöller Plateau indicate that the peaks (>3400 m, asl) have been ice-free since about 67 ka. Several glacier tongues descended from the icefields through eight main glacial valleys (three on the western and five on the eastern side). The outwash fan along the SW front of Mt. Aladağlar represents the oldest (about 136 ka) glacial deposits developed during the previous glacial cycle. Four other outwash fans yielded ages that range from about 97 ka to 65 ka, indicating deposition during the last cycle. On the western side, the oldest moraine ages (about 46 ka and 38 ka) from two valleys show pre-LGM advances that could be considered the maximum extent of local glaciers. Intriguingly, global LGM moraines (about 23-19 ka) are relatively small and preserved only at high elevations (>2450 m asl). Recalculated ages of seven consecutive moraines in the longest (17.2 km) and the deepest valley on the eastern side indicate Late Glacial (about 15 ka) to Early Holocene (about 12 ka) deglaciation. Several small moraines also show deglaciation (about 12-10 ka) corresponding to the Younger Dryas and the onset of the Holocene. The ages obtained from Mt. Aladağlar indicate a complete range of glacial conditions during pre-LGM, global LGM, Late Glacial, Younger Dryas, and Early Holocene in the eastern Mediterranean. • A continuous last glacial cycle 36Cl glacial chronology from Mt Aladağlar, Türkiye. • 105 moraine, landslide, glacial outwash boulders and limestone bedrock ages. • Three local icefields (>3000 m) and eight main glacial valleys. • Oldest moraines (46 ka) indicate the maximum extent of local glaciers. • Last Glacial Maximum, Late Glacial, Younger Dryas, and Early Holocene glaciers. [ABSTRACT FROM AUTHOR]

Abstract Climatic oscillations during the last glacial maximum (LGM) significantly affected the distribution patterns and genetic structure of extant plants. Northeast China (NEC) is a major biodiversity center in East Asia, and the influence of historical climate change on NEC populations is critical for understanding species responses to future climate change. However, only a few phylogeographic studies of cool temperate deciduous tree species have been conducted in the area, and results are inconsistent for species with different niches or distribution areas. We employed multiple chloroplast and nuclear markers to investigate the genetic structure of two ecologically contrasting species, Betula platyphylla and B. ermanii, in NEC. Rare haplotypes were identified in the chloroplast genome of these species, and both exhibited high levels of nucleotide diversity based on a fragment of the nuclear gene G3PDH and microsatellites. Moreover, significant phylogeographic structure was detected for B. platyphylla, suggesting that these populations had recolonized from independent glacial refuges, whereas no genetic structure was found for B. ermanii. OPEN RESEARCH BADGES The nSSR datasets used in the current study and the table of pairwise FST (below diagonal) and its standardized F'ST (above diagonal) among 25 populations based on seven SSRs are available from the Dryad (DOI: https://doi.org/10.5061/dryad.230d176). Sequences generated from this study were deposited in GenBank under Accession nos. KY199568–KY200162 and MK819541–MK819970.

Abstract The current phylogeographic pattern of European brown bears (Ursus arctos) has commonly been explained by postglacial recolonization out of geographically distinct refugia in southern Europe, a pattern well in accordance with the expansion/contraction model. Studies of ancient DNA from brown bear remains have questioned this pattern, but have failed to explain the glacial distribution of mitochondrial brown bear clades and their subsequent expansion across the European continent. We here present 136 new mitochondrial sequences generated from 346 remains from Europe, ranging in age between the Late Pleistocene and historical times. The genetic data show a high Late Pleistocene diversity across the continent and challenge the strict confinement of bears to traditional southern refugia during the last glacial maximum (LGM). The mitochondrial data further suggest a genetic turnover just before this time, as well as a steep demographic decline starting in the mid‐Holocene. Levels of stable nitrogen isotopes from the remains confirm a previously proposed shift toward increasing herbivory around the LGM in Europe. Overall, these results suggest that in addition to climate, anthropogenic impact and inter‐specific competition may have had more important effects on the brown bear's ecology, demography, and genetic structure than previously thought.

Palaeoglacier modelling is an important approach for reconstructing the palaeoclimate. The timing of glaciations in the central part of the Gangdise Mountains has been constrained previously, but the palaeoclimate remains unclear. In this paper, the palaeo-temperature and precipitation of the early marine isotope stage (MIS) 2, the Last Glacial Maximum (LGM), and the early Holocene were reconstructed using coupled mass balance and ice flow models. The results show that a series of temperature changes (ΔT) and precipitation factors (Fp) resulted in optimum palaeoglacial extents. The modelled palaeoglaciers during the early MIS 2, the LGM, and the early Holocene cover areas of ~18.1 km2, ~17.4 km2, and ~16.3 km2, respectively, with ice volumes of ~2.18 km3, ~1.99 km3, and ~1.95 km3, respectively. Previous studies on ice cores, pollen samples, and lake sediments were referenced to narrow the range of palaeo-temperatures and precipitations. The reconstructed temperatures during the early MIS 2, LGM, and early Holocene were constrained to 2.4–2.9 °C, 2.15–3.05 °C, and 0.95–1.5 °C lower than today, respectively. Their precipitation levels were 60–80%, 50–80%, and 100–150% of the present-day level, respectively.