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The most abundant evidence of Pampean Pleistocene human presence are modified bones, as lithic procurement sites located farther than 300 km away. Therefore, we focused on the study of bone modifications, in particular cut and percussion marks. We studied Pampean paleontological collections of Argentine and European museums as an alternative resource of previously unnoticed human modification evidences. We compared marks characteristics with those of archaeological collections from diverse climatic and cultural adaptations, from middle Pleistocene sites (Vallonet, Atapuerca, Lazaret, Arago and Terra Amata) to terminal Pleistocene ones (Abri Pataud, Isturiz and La Vache). Marks typologies were defined, leading to the identification of a particular cutmark that we named double parallel considered as highly diagnostic of anthropic use of lithic artifacts. We also propose that hafted artifacts were used on carcass processing. Perimortem bone modifications are classified in relation with mark morphology (e.g., percussion striae), inferred gesture or action (e.g., breakage of diaphysis), and inferred objective of that action (e.g., marrow extraction). The megafauna specimens analyzed from the historical collections (d'Angelis-Vilardebó, 1847, Muñiz-Dupotet, 1842 and Breton-Bonnement, 1881) present modifications compatible with dismemberment, defleshing, tongue and masseter extraction, and utilization as anvils. The lack of contextual data (location, stratigraphy) and the loss due to museum selection/collecting of accompanying material prevent paleoenvironmental and paleoecological inferences. Regional geology indicates that most of the historical collections were exhumed in riverbank cuts with ages between 70 and 13 ky BP. Preliminary direct dating presents evidence of a Pampean human occupation, at least, since OIS 2. [ABSTRACT FROM AUTHOR]

The stable carbon isotope compositions of C 3 plants are controlled by the carbon isotope composition of atmospheric CO 2 ( δ 13 C a ) and by the stomatal response to water stress. These relationships permit the reconstruction of ancient environments and assessment of the water use efficiency of forests. It is currently debated whether the δ 13 C values of C 3 plants are also controlled by atmospheric pCO 2 . Here I show that globally-averaged speleothem δ 13 C values closely track atmospheric pCO 2 over the past 90 kyr. After accounting for other possible effects, this coupling is best explained by a C 3 plant δ 13 C sensitivity of − 1.6 ± 0.3 ‰ / 100 ppmV CO 2 during the Quaternary. This is consistent with 20th century European forest tree ring δ 13 C records, providing confidence in the result and suggesting that the modest pCO 2 -driven increase in water use efficiency determined for those ecosystems and simulated by land surface models accurately approximates the global average response. The δ 13 C signal from C 3 plants is transferred to speleothems relatively rapidly. Thus, the effect of atmospheric pCO 2 should be subtracted from new and existing speleothem δ 13 C records so that residual δ 13 C shifts can be interpreted in light of the other factors known to control spleleothem δ 13 C values. Furthermore, global average speleothem δ 13 C shifts may be used to develop a continuous radiometric chronology for Pleistocene atmospheric pCO 2 fluctuations and, by correlation, ice core climate records. [ABSTRACT FROM AUTHOR]

Earth's climate has undergone dramatic shifts between glacial and interglacial time periods, with high-latitude temperature changes on the order of 5-10 °C. These climatic shifts have been associated with major rearrangements in the deep ocean circulation and stratification, which have likely played an important role in the observed atmospheric carbon dioxide swings by affecting the partitioning of carbon between the atmosphere and the ocean. The mechanisms by which the deep ocean circulation changed, however, are still unclear and represent a major challenge to our understanding of glacial climates. This study shows that various inferred changes in the deep ocean circulation and stratification between glacial and interglacial climates can be interpreted as a direct consequence of atmospheric temperature differences. Colder atmospheric temperatures lead to increased sea ice cover and formation rate around Antarctica. The associated enhanced brine rejection leads to a strongly increased deep ocean stratification, consistent with high abyssal salinities inferred for the last glacial maximum. The increased stratification goes together with a weakening and shoaling of the interhemispheric overturning circulation, again consistent with proxy evidence for the last glacial. The shallower interhemispheric overturning circulation makes room for slowly moving water of Antarctic origin, which explains the observed middepth radiocarbon age maximum and may play an important role in ocean carbon storage. [ABSTRACT FROM AUTHOR]

In the process of reviewing pollen data from Hokkaido and Sakhalin, three facts were confirmed. 1) The climate was revised to one colder than the Last Glacial Maximum (LGM) during the last deglaciation in the last glacial period, called the Kenbuchi Stadial, which was related to the southward shift of the summer position of the Kuroshio-Oyashio sea current boundary, which affected not only northern Hokkaido but also eastern Hokkaido and northwestern Sakhalin. 2) From marine isotope stage 3–8000 Cal. yr BP, grassland and mire that developed in Hokkaido were characterized by expanded spikemoss, which grows in snowpatch grassland and mire in the alpine zone of Hokkaido and northern Honshu today. 3) During the LGM, thermokarst depressions, so-called “alas,” likely formed in eastern Hokkaido along the Sea of Okhotsk based on the yield of the aquatic plants Menyanthes and Botryococcus in LGM sediments. [ABSTRACT FROM AUTHOR]

South China and Indochina host striking species diversity and endemism. Complex tectonic and climatic evolutions appear to be the main drivers of the biogeographic patterns. In this study, based on the geologic history of this region, we test 2 hypotheses using the evolutionary history of Microhyla fissipes species complex. Using DNA sequence data from both mitochondrial and nuclear genes, we first test the hypothesis that the Red River is a barrier to gene flow and dispersal. Second, we test the hypothesis that Pleistocene climatic cycling affected the genetic structure and population history of these frogs. We detect 2 major genetic splits that associate with the Red River. Time estimation suggests that late Miocene tectonic movement associated with the Red River drove their diversification. Species distribution modeling (SDM) resolves significant ecological differences between sides of the Red River. Thus, ecological divergence also probably promoted and maintained the diversification. Genogeography, historical demography, and SDM associate patterns in southern China with climate changes of the last glacial maximum (LGM), but not Indochina. Differences in geography and climate between the 2 areas best explain the discovery. Responses to the Pleistocene glacial-interglacial cycling vary among species and regions. [ABSTRACT FROM AUTHOR]

Aim Biodiversity patterns reflect both ecological and evolutionary processes interacting with geographical variation in climate and the current and historical connectivity between land areas. We sought to disentangle these effects in explaining the organization of ant diversity across geographical areas and islands in East Asia. Location The Japanese Archipelago including the Ryukyu and Ogasawara Islands, Taiwan and coastal continental regions of Korea, China and Russia. Methods We aggregated species occurrence records from published literature, specimen databases and museum records, and compiled climatic variables for islands and politically defined continental areas. Current and historical land connections in the Last Glacial Maximum were determined using bathymetric databases. We analysed factors driving patterns of Simpson composition dissimilarity using multiple regression of distance matrices. Results Temperature was the largest driver of dissimilarity among areas, with geographical distance and historical land contiguity also being important. Current land contiguity had no detectable effect. Main conclusions We found climate to be a primary driver of ant diversity patterns on large scales, consistent with previous work on ants and other organisms. Interestingly, land connectivity during historical periods of low sea level was more important than current land connectivity in explaining faunal similarities. This implies that despite the potential overwater dispersal of ants, overland dispersal via transient land connections is a more important driver of regional-scale biogeographical pattern in East Asia. [ABSTRACT FROM AUTHOR]

In the Mérida Andes, a detailed deglaciation history reconstruction is difficult to achieve due to scattered deglaciation chronologies available. This paper contributes with 24 exposure ages of glacial landforms sampled in the Gavidia valley. Exposure ages were obtained based on terrestrial cosmogenic nuclide 10 Be dating. Results indicate deglaciation mainly occurred between ∼21 ka and 16.5 ka and the complete deglaciation occurred at ∼16.0 ka. The glacier retreated in two different phases. The oldest one occurred since the LGM until middle OtD or the local climate event El Caballo Stadial. The youngest phase occurred at ages younger than ∼16.5 ka until complete deglaciation. A combination of topographic features and changes in the paleoclimate conditions at the end of the El Caballo Stadial seems leaded the fastest former glacier extinction. The topographic feature which seems contributed to the fastest glacier extinction was the low valley bottom slopes. In addition, exposure ages of the Gavidia valley were integrated with deglaciation chronologies from the central Mérida Andes to compare deglaciation histories. Asynchronous deglaciation histories were observed. Local paleotemperatures and paleoprecipitations contrasts, different valleys aspects, insolation and catchments steepness could explain different deglaciation histories. [ABSTRACT FROM AUTHOR]

The saiga antelope ( Saiga tatarica ), which today is a specialist steppe herbivore adapted to long-distance migrations in massive herds, appeared at irregular intervals in the Late Pleistocene Europe. Its special ecological requirements limited the number and timing of dispersal events. In the Eemian the saiga was absent on the continent. During MIS 5d-a, MIS 4 and MIS 3 its range was restricted to steppe areas north of the Black Sea. In MIS 2 and the Late Glacial (MIS 1) this species was able to colonize Central Europe at least three or four times and Western Europe at least twice. The most successful second migration dates to part of GS-2c, GS-2b and part of GS-2a, from ca. 19.5 to 15.3 cal ka BP when the saiga reached southern France. During GI-1d (Older Dryas), ca. 14.0 cal ka BP, the saiga reached England. The first migration during the GI-2 warm phase (ca. 23.7–23.3 cal ka BP) and the last one (ca. 13.5 cal ka BP) in the GI–1c 2 cool phase were probably restricted to Central Europe. [ABSTRACT FROM AUTHOR]

Any future changes in the volume of Antarctica’s ice sheets will depend on the dynamic response of outlet glaciers to shifts in environmental conditions. In the Transantarctic Mountains, this response is probably heavily dependent on the geometry of the system, but few studies have quantified the sensitivity of these glaciers to environmental forcings. Here we investigated the controls, along-flow sensitivity and time-dependent dynamics of Skelton Glacier. Three key outcomes were: i) present-day flow is governed primarily by surface slope, which responds to reduced valley width and large bed undulations, ii) Skelton Glacier is more susceptible to changes in atmospheric temperature than precipitation through its effect on basal sliding near the grounding line, and iii) under conditions representative of Pliocene and Quaternary climates large changes in ice thickness and velocity would have occurred in the lower reaches of the glacier. Based on these new quantitative predictions of the past and present dynamics of Skelton Glacier, we suggest that similar Transantarctic Mountain outlet glaciers could experience greater ice loss in their confined, lower reaches through increased basal sliding and ocean melt under warmer-than-present conditions. These effects are greatest where overdeepenings exist near the grounding line. [ABSTRACT FROM AUTHOR]

The analysis of a database of radiocarbon ages is proposed as a tool for investigating major glaciofluvial systems of the Last Glacial Maximum (LGM) in the Alpine foreland, and their relations with glacier dynamics and climatic fluctuations. Our research concerns the Brenta megafan (NE Italy), where 110 radiocarbon dates integrate a robust regional stratigraphic and palaeoclimatic framework. Age-depth models allowed us to calculate sedimentation rates, while the time distribution of peat layers, which recurrently formed in this region during the LGM, were estimated through meta-analysis. The reliability of statistical results was carefully evaluated using Pearson and Spearman coefficients. Sedimentation rates in the Brenta megafan markedly fluctuated during LGM: ≈1.8 m/ka between 40 and 26.7 ka cal BP; ≈3 m/ka between 26.7 and 23.8 ka cal BP and ≈1.4 m/ka from 23.8 to 17.5 ka cal BP, when the distributary system deactivated due to fan-head trenching. This is evidence that sediment input and routing in the glaciofluvial distributary system was particularly efficient during the central part of LGM, when glaciers were stable at their outermost position. Meta-analysis indicates an increase in peat formation in correspondence with global (Heinrich Event 3 and/or the Greenland Interstadial 5.1 and 4 for the 30.5, 29.6 and 28.8 ka cal BP peaks) and regional (23.5 ka cal BP) wet events. Other peaks at 22.2, 21.8, 20.2 and 19 ka cal BP correlate with fluctuations of south-eastern Alpine glaciers. Significant peat formation continued until ≈18 ka cal BP, when the last peak occurred. A marked decrease in peat formation is recorded concomitantly with the onset of Heinrich Event 2 (i.e. the 26 ka cal BP trough). The good correspondence of sedimentary events in the Brenta glaciofluvial system with the dynamics of glaciers and glaciofluvial and lacustrine systems in the southern Eastern Alps suggests a common climatic forcing on the whole region during the LGM. Peat layer formation in the floodplain fens increased significantly in correspondence with glacier withdrawals and/or wetter climatic episodes, constituting a good proxy for climatic fluctuations during glacial periods. It also allows correlations across different continental environments and regions in the northern hemisphere. [ABSTRACT FROM AUTHOR]

Although geomorphological evidences of Quaternary glaciations of the Southern Carpathians were extensively studied and discussed, the limited number of chronological studies resulted in poor and controversial knowledge on the age of glaciations and deglaciation of the area. We use new and recalculated in situ produced 10 Be surface exposure ages of glacial landforms to shed light on the age of the maximum glacial extent and the glacier oscillations during the last deglaciation process on the northern side of the Retezat Mountains. According to our data, the maximum ice extent documented by preserved moraines occurred around 21.0 − 1.5 + 0.8 ka, coincident with the global Last Glacial Maximum (LGM). The deglaciation process during the Lateglacial was characterized by two glacial advances at 18.6 − 0.8 + 0.9 and 16.3 − 0.6 + 0.6 ka. Inferred stabilization date of the penultimate glacial stage at 15.2 − 0.8 + 0.7 ka was closely followed by the abrupt warming at the onset of the Bølling/Allerød documented by a local chironomid-based temperature reconstruction. The last small glacier advance was dated to 13.5 − 0.4 + 0.5 ka. These recessional/readvance phases agree with other European glacial chronologies. [ABSTRACT FROM AUTHOR]

The present paper provides new information on Pleistocene glacial activity in a mountainous area of the Iberian Central System. A sediment analysis associated with Pleistocene modelling was carried out using: (1) granulometric and morphometric procedures, (2) quartz grain microtexture techniques (SEM) to discriminate between glacial and no glacial origins of sediments, (3) clay X-ray diffraction study to determine intra-Pleistocene climate variability, and (4) optically stimulated luminescence (OSL) absolute dating. The results show that the sediments were formed in two different phases associated with glacial dynamics, one of them was 35–30 ky BP and another was 25–20 ky BP, separated by a short intermediate warm-wet period. Identification of glacial phenomena is new for the northern slopes of the Guadarrama Mountains (facing the north Meseta, Duero basin), although they are not unusual within the general context of the Iberian Central System. From the data provided, we deduce that glaciation in these mountains was much more intense and widespread than had previously been thought because, on the northern slopes, glaciers occupied large areas reaching the base of the mountains. The evidence favours new interpretations of Pleistocene morphology in the centre of the Iberian Peninsula and, by extension, on the southwestern edge of Europe; it also highlights the sensitivity of mountainous areas with regard to Quaternary climate changes. [ABSTRACT FROM AUTHOR]

At the last glacial maximum, the Gravettian human groups moved to southern European Peninsulas: Iberian, Italian, Balkan and the gulfs: Tyrrhenian, Adriatic, Aegean and around the Black Sea (a lake at this time). There, they differentiated: Solutrean in Western Europe, Epigravettian in Central Europe and in Eastern Europe. Human groups, constrained in their new southern territories, returned to a system of small territories and low mobility, which required them to change the food resource system (gregarious mammal hunting replacing migratory herd hunting), sources of raw material procurement (reuse of quartzite), and, as a result, technology (return to flake knapping, importance of lamellar knapping) and industry. This local opportunistic strategy involved territories of less than 1000 km 2 and low mobility. The climate variations of the last glacial maximum reveal two wetter episodes, clearly visible in the sequences of loess of Central and Eastern Europe and in non-anthropogenic records around 20–19 000 BP and 18.5–17 000 BP. During these two episodes, human groups moved northward during the summer, in a seasonal mobility strategy, involving hunting of migratory animals and use of outcrops of good flint. These two systems existed during the last glacial maximum in Western, Central, and Eastern Europe, where, despite typological differences in assemblages, common characteristics may be highlighted. [ABSTRACT FROM AUTHOR]

Background: Adolescence is a period of vulnerability regarding the emergence of internalizing disorders such as anxiety. Anxiety symptoms can persist into adulthood and involve negative outcomes. The aim of the study was to examine the developmental trajectory of several anxiety subtypes by gender, in a non-clinical sample of early adolescents over three phases. Method: Using a prospective design, 1514 children (mean-age = 10.23, SD = 1.23) underwent anxiety and depression screening in the first phase. Then, 562 children (mean-age = 11.25, SD = 1.04) participated in the second phase, and 242 (mean-age = 13.52; SD = .94) were followed up in the third phase. The Screen for Child Anxiety Related Emotional Disorders was administered in all phases. Developmental trajectories of anxiety scores were examined using latent growth modelling. Results: Manifestations of social phobia and generalized anxiety disorders remained stable. Gender differences were found: boys showed a significant decrease in the developmental trajectories of somatic/panic symptoms, separation anxiety disorder and total anxiety in comparison to girls. Conclusions: The data indicate that anxiety symptomatology is a significant clinical phenomenon in school-age children but that it does not increase throughout early adolescence. It is important to identify developmental patterns for anxiety subtypes and in relation to gender. [ABSTRACT FROM AUTHOR]

The deep Pacific Ocean holds the largest oceanic reservoir of carbon which may interchange with the atmosphere on climatologically important timescales. The circulation of the deep Pacific during the Last Glacial Maximum (LGM), however, is not well understood. Neodymium (Nd) isotopes of ferromanganese oxide coatings precipitated on planktonic foraminifera are a valuable proxy for deep ocean water mass reconstruction in paleoceanography. In this study, we present Nd isotope compositions ( ε Nd ) of planktonic foraminifera for the Holocene and the LGM obtained from 55 new sites widely distributed in the Pacific Ocean. The Holocene planktonic foraminiferal ε Nd results agree with the proximal seawater data, indicating that they provide a reliable record of modern bottom water Nd isotopes in the deep Pacific. There is a good correlation between foraminiferal ε Nd and seawater phosphate concentrations ( R 2 = 0.80 ), but poorer correlation with silicate ( R 2 = 0.37 ). Our interpretation is that the radiogenic Nd isotope is added to the deep open Pacific through particle release from the upper ocean during deep water mass advection and aging. The data thus also imply the Nd isotopes in the Pacific are not likely to be controlled by silicate cycling. In the North Pacific, the glacial Nd isotopic compositions are similar to the Holocene values, indicating that the Nd isotope composition of North Pacific Deep Water (NPDW) remained constant (−3.5 to −4). During the LGM, the southwest Pacific cores throughout the water column show higher ε Nd corroborating previous studies which suggested a reduced inflow of North Atlantic Deep Water to the Pacific. However, the western equatorial Pacific deep water does not record a corresponding radiogenic excursion, implying reduced radiogenic boundary inputs during the LGM probably due to a shorter duration of seawater–particle interaction in a stronger glacial deep boundary current. A significant negative glacial ε Nd excursion is evident in mid-depth (1–2 km) cores of the eastern equatorial Pacific (EEP) which may suggest a stronger influence of NPDW return flow to the core sites and decreased local input in the EEP. Taken together, our Nd records do not support a dynamically slower glacial Pacific overturning circulation, and imply that the increased carbon inventory of Pacific deep water might be due to poor high latitude air–sea exchange and increased biological pump efficiency in glacial times. [ABSTRACT FROM AUTHOR]

Vegetation and climate during the last ice age and the Last Glacial Maximum (LGM, ∼23,000–19,000 cal BP) were considerably different than during the current interglacial (Holocene). Cold climatic conditions and growing ice-sheets during the last glaciation radically reduced forest extent in Europe to a restricted number of so-called “refugia”, mostly located in the southern part of the continent. On the basis of paleobotanical analyses the Euganian Hills (Colli Euganei) in northeastern Italy have previously been proposed as one of the northernmost refugia of temperate trees (e.g. deciduous Quercus, Tilia, Ulmus, Fraxinus excelsior, Acer, Abies alba, Fagus sylvatica, Carpinus and Castanea ) in Europe. In this study we provide the first quantitative, vegetation independent summer air temperature reconstruction for Northern Italy spanning the time ∼31,000–17,000 cal yr BP, which covers the coldest periods of the last glacial, including the LGM and Heinrich stadials 1 to 3. Chironomids preserved in a lake sediment core from Lago della Costa (7m a.s.l.), a small lake at the south-eastern edge of the Euganean Hills, allowed quantitative reconstruction of Full and Late Glacial summer air temperatures using a combined Swiss-Norwegian temperature inference model based on chironomid assemblages from 274 lakes. Chironomid and pollen evidence from Lago della Costa derives from finely stratified autochthonous organic gyttja sediments, which excludes major sediment mixing or reworking. After reconstructing paleo-temperatures, we address the question whether climate conditions were warm enough to permit the local survival of temperate tree species during the LGM and whether local expansions and pollen-inferred contractions of temperate tree taxa coincided with chironomid-inferred climatic changes. Our results suggest that chironomids at Lago della Costa have responded to major climatic fluctuations such as temperature decreases during the LGM and Heinrich stadials. The vegetation of the Euganean Hills shows responses to these climatic oscillations although the effects of temperature changes were probably also strongly influenced by changes in humidity. Reconstructed July air temperatures at Lago della Costa never fell below 10–13 °C (error range of reconstruction ∼ ±1.5–1.6 °C), which is considerably above the limit considered necessary for forest growth (8–10 °C). Instead rather mild climatic conditions prevailed ∼31,000–17,000 cal yr BP with average summer temperatures between ∼12 and 16 °C, which most likely allowed survival of temperate tree taxa in the warmest (and moistest) microhabitats of the Euganean Hills during the LGM. Only assuming local survival is it possible to explain the repeated expansions and collapses of temperate trees at Lago della Costa which faithfully accompanied the climatic oscillations. [ABSTRACT FROM AUTHOR]

Although Siberia was inhabited by modern humans at an early stage, there is still debate over whether it remained habitable during the extreme cold of the Last Glacial Maximum or whether it was subsequently repopulated by peoples with recent shared ancestry. Previous studies of the genetic history of Siberian populations were hampered by the extensive admixture that appears to have taken place among these populations, because commonly used methods assume a tree-like population history and at most single admixture events. Here we analyze geogenetic maps and use other approaches to distinguish the effects of shared ancestry from prehistoric migrations and contact, and develop a new method based on the covariance of ancestry components, to investigate the potentially complex admixture history. We furthermore adapt a previously devised method of admixture dating for use with multiple events of gene flow, and apply these methods to whole-genome genotype data from over 500 individuals belonging to 20 different Siberian ethnolinguistic groups. The results of these analyses indicate that there have been multiple layers of admixture detectable in most of the Siberian populations, with considerable differences in the admixture histories of individual populations. Furthermore, most of the populations of Siberia included here, even those settled far to the north, appear to have a southern origin, with the northward expansions of different populations possibly being driven partly by the advent of pastoralism, especially reindeer domestication. These newly developed methods to analyze multiple admixture events should aid in the investigation of similarly complex population histories elsewhere [ABSTRACT FROM AUTHOR]

The Indo-Pacific Warm Pool holds a unique place on the globe. It is a large area [>30 × 10 km] that is characterised by permanent surface temperature >28 °C and is therefore called the 'heat engine' of the globe. High convective clouds which can reach altitudes up to 15 km generate much latent heat in the process of convection and this area is therefore called the 'steam engine' of the world. Seasonal and contrasting monsoonal activity over the region is the cause for a broad seasonal change of surface salinities, and since the area lies along the path of the Great Ocean Conveyor Belt, it is coined the 'dilution' basin due to the high incidence of tropical rain and, away from the equator, tropical cyclones contribute to a significant drop in sea water salinity. Discussion about what may happen in the future of the Warm Pool under global warming is presented together with a description of the Warm Pool during the past, such as the Last Glacial Maximum when sea levels had dropped by ~125 m. A call for urgent monitoring of the IPWP area is justified on the grounds of the significance of this area for global oceanographic and climatological processes, but also because of the concerned threats to human population living there. [ABSTRACT FROM AUTHOR]

An eyed bone needle fragment found in Shizitan 29 site, Shanxi Province, dated to ca . 23–26 ka cal BP, is one of the early needles with a precise stratigraphic context and date among the open-air Palaeolithic sites in North China. Although the needle was found broken, based on microwear observation and experiments in making and using bone needles, we conclude that it had been used for sewing. Further archaeological evidence, including a sandstone needle-shaping stone, drilling tools, perforated ornaments, and microscopic evidence of thread, support the presence of a bone needle at the Shizitan 29 site. It was the same type as the bone needles used in Siberia during the Late Pleistocene, and the use of needles at Shizitan was one of the strategies for making warm clothes to adapt to the coming of the Last Glacial Maximum (LGM, 24,000–18,000 cal BP). [ABSTRACT FROM AUTHOR]

Aim Our research attempts to provide an explicit explanation of human-biome interactions during the last glacial period and how these have influenced current human population genetics at the global scale. Publications to date have not addressed this topic. Location World-wide. Methods Using climate, terrain, hydrographic, fossil pollen and plant-macrofossil data we developed a model of the distribution of biomes during climate deteriorations of the last glacial period. Subsequently, we analysed current human genetic diversity, the origins of genetic lineages and Palaeolithic human sites in relation to the inferred biomes. Results Our analyses indicated that: (1) current human Y- DNA diversity, the places of origin of human Y- DNA lineages and the distribution of Palaeolithic human settlements are best explained by distance from savanna and dry woodland during a series of glacial maxima, and (2) during periods of relatively benign climate conditions, humans dispersed through areas of high primary productivity while avoiding dense forest cover. Main conclusions In a metapopulation of Palaeolithic humans, the biome of savanna and dry woodland supported source populations and other biomes acted as sinks. Present-day genetic, phenotypical and linguistic differences are largely related to discontinuity of and impeded migration between human source populations during glacial periods, rather than simply geographical distance, and in the post-glacial period there has not been enough time for displacements and admixture of human populations to completely blur these differences. [ABSTRACT FROM AUTHOR]

The distributions of frozen ground and active layer thickness (ALT) during the last glacial maximum (LGM) and pre-industrial periods in China were investigated using Coupled Model Intercomparison Project Phase 5 (CMIP5) model experiments. Compared to the pre-industrial period, the LGM climate was ~ 5 °C colder and featured significantly higher freezing indices on the Tibetan Plateau and in Northeast China. Frozen ground expanded widely in the LGM. The extents of permafrost and seasonally frozen ground in China were 4.11 × 10 6 km 2 and 4.97 × 10 6 km 2 , respectively, which are 2.42 × 10 6 km 2 larger and 1.45 × 10 6 km 2 smaller, respectively, than the pre-industrial levels. Moreover, the colder climate and longer duration also resulted in LGM ALT values that were 1.3 m less than the pre-industrial values in the permafrost areas common to both periods. Altitudinal permafrost was present mainly on the Tibetan Plateau and adjacent mountains in West China between 28°N and 41°30′N and covered an area of ~ 2.63 × 10 6 km 2 . Latitudinal permafrost was present mainly in Northeast China and occupied an area of 1.48 × 10 6 km 2 . The southern limit of latitudinal permafrost was located ~ 10° of latitude farther south during the LGM than during the pre-industrial period. The LGM simulation results agree reasonably well with previous reconstructions, with the exception of an underestimation in the permafrost extent. Although relatively high-level disagreement exists between the models in terms of the exact locations of the southern limits, the ensemble average is still able to represent the large-scale spatial pattern of frozen ground remarkably well. [ABSTRACT FROM AUTHOR]

The evolution of precipitation is a key question concerning future climatic changes, especially in regions like the Mediterranean area which are currently prone to droughts. The influence of atmospheric circulation changes (in the mid-latitude westerlies or in the strength of the subtropical subsidence), along with changes in local mechanisms generating precipitation (such as convection) make it difficult to predict precipitation changes confidently over this area. Understanding its governing mechanisms is crucial. A possible approach is to test our understanding on different documented past climatic contexts. This paper focuses on the Last Glacial Maximum period (LGM) over the western Mediterranean region and puts in perspective the available information inferred from paleo-climatic records and the outputs of nine global climate models. We first review the available information on LGM precipitation in this region and find that the environmental conditions prevailing at this period range from humid to semi-arid, depending on the proxies. Model outputs from the PMIP3-CMIP5 database also yield a wide range of mean annual responses in this area, from wetter to drier conditions with respect to the pre-industrial period. This variety of responses allows to investigate the mechanisms governing LGM precipitation in the western Mediterranean area. Over the Iberian Peninsula and northern Morocco, most models simulate a larger amount of LGM precipitation in winter w.r.t. the pre-industrial period. This feature is mainly due to the large-scale effect of the southward shift of the North Atlantic jet stream, which is closely associated with the surface air temperature changes over the northwestern North Atlantic. In summer, precipitation changes mainly result from convection and are correlated to local surface air temperature anomalies, highlighting the key role of local processes. These contrasted changes in winter and summer, linked to different mechanisms, could explain the range of various signals derived from paleo-climatic archives, especially if the climatic indicators are sensitive to seasonal precipitation. [ABSTRACT FROM AUTHOR]

Albania is a possible stepping-stone for the dispersal of Homo sapiens into Europe, since Palaeolithic traces (namely from the so-called Uluzzian culture) have been discovered in neighboring Greece and Italy. After two years of searching for evidence of modern humans in Albania we here report on excavated test trenches representing two time slices: an Aurignacian open-air site from southern Albania and two Epigravettian cave sites in central and northern Albania—areas heretofore archaeologically unknown. The new Albanian data fill a gap in the eastern Adriatic archaeological record for Marine Isotope Stages 3 and 2. Adding current knowledge of Late Pleistocene landscape evolution, a “contextual area model” can be constructed describing the habitats of these human populations. [ABSTRACT FROM PUBLISHER]

Repeated global climatic cooling and warming cycles during the Pleistocene played a major role in the distribution and evolution of the Earth biota. Here, we integrate phylogeography, coalescent-based Bayesian estimation of demographic history, and species distribution modeling (SDM) to understand the genetic patterns and biogeography of the flowering dogwood, Cornus florida subsp. florida L., since the Last Glacial Maximum (LGM). Natural populations of the species are severely threatened by dogwood anthracnose. We genotyped 306 plants from 73 locations of the species across most of its native distribution with three DNA regions from the plastid genome, ndhF-rpl32, rps16 and trnQ-rps16. The genealogy and haplotype network reconstruction revealed two haplotype lineages diverging ≈3.70 million years ago. We detected no clear geographic structuring of genetic variation, although significant local structure appeared to be evident, likely due to a combination of substantial localized seed dispersal by small mammals and small population size/limited sampling at a location. The spatial distribution of haplotype frequencies, estimated population demographic history, and results from hindcasting analysis using SDM suggested refugia in southeastern North America and population reduction during the LGM, followed by rapid post-glacial expansion to the north. Forecasting analysis using SDM predicted range shifts to the north under ongoing global warming. Our results further suggested that gene flow via seed dispersal has been high but insufficient to counter the effect of genetic drift. This study demonstrates the benefit of integrating genetic data and species distribution modeling to obtain corroborative evidence in elucidating recent biogeographic history and understanding of genetic patterns and species evolution. [ABSTRACT FROM AUTHOR]

Molecular studies support the hypothesis that Corsica Island was a glacial refugium for a number of forest birds during the Pleistocene. We focused on the Corsican nuthatch ( Sitta whiteheadi ), an endemic passerine strongly associated with the laricio pine ( Pinus nigra laricio ). The range of laricio pine has been impacted by the Pleistocene glacial periods and forest has been recently fragmented by cutting and fires. Using both molecular (mitochondrial and nuclear) and morphological characters, we assessed the variation within the nuthatch population. Our results are consistent with the hypothesis that the Corsican nuthatch endured through the late Pleistocene and Holocene climatic variations, and sustained the subsequent cycles of forests reduction/expansion. The results also suggest that the recent anthropization of the landscape resulted in the isolation of a cluster of populations in the northern part of the island. The fragmentation of the habitat of the nuthatch may impede the future of the bird by creating isolated population units between which the gene flow is reduced. [ABSTRACT FROM AUTHOR]

Although deglaciation is one of the crucial factors controlling the stability of slopes in high mountains, the chronological response of rock slope failure (RSF) to glacier retreat still remains poorly known. Here we provide the first cosmogenic ( 10 Be) age constraints on prominent rock avalanches and rockfalls (collectively termed ‘rock slope failures’ – RSFs) from the Tatra Mountains, the highest mountain range with the most pronounced glacier morphology within the Carpathians. Six representative RSFs were selected for surface exposure dating in the mountain range. Two sites are situated in the western part with less pronounced local relief and gentler slope gradient, and four come from the highest eastern part with oversteepened rock slopes. Our dataset also contains the largest known RSF in the Tatra Mountains; the Koprová rock avalanche with a volume of ~ 5.4 × 10 6 m 3 . Based on 26 10 Be dated boulders, the weighted mean ages of individual RSF accumulations range between 20.2 ± 1.2 and 10.1 ± 0.3 ka. Our results suggest that smaller, structurally predisposed failures (mainly rockfalls) in the steepest parts of the mountains reacted immediately (i.e. a few hundred years) to deglaciation, whereas more complex slope deformations in terrain with lower local relief, involving the largest rock avalanche in the Tatra Mountains, experienced a substantial time lag (i.e. several millennia) in respect to ice retreat. In the case of delayed RSFs, their origin can be well correlated with warmer and more humid periods in the Lateglacial/early Holocene such as the Bølling–Allerød chronozone and after the onset of the Holocene. [ABSTRACT FROM AUTHOR]

Magnetic characterization of sediments from the Ulleung basin in the East Sea (Japan Sea) was carried out to decipher changes in environmental conditions over the last ~ 39,000 years. Magnetic susceptibility (χ), intensities of natural remanent magnetization (NRM), anhysteretic remanent magnetization (ARM), partial ARM (pARM), and saturation isothermal remanent magnetization (SIRM) were measured. For selected samples, IRM acquisition, hysteresis and first-order reversal curve (FORC) measurements were made. The ratios of rock-magnetic parameters, such as χ ARM /χ, SIRM/ARM and S-ratio, were determined to identify magnetic grain size and mineralogical variations along with electron microscope observations of magnetic mineral extracts. Down-core variations in rock-magnetic parameters for the 5.21-m-long sediment core reveal distinct intervals with different grain size, concentration and composition of magnetic minerals. The uppermost portion and the high magnetic intensity zone (HIZ) in marine isotope stage (MIS) 2 are characterized by higher concentrations of fine-grained magnetite, whereas the MIS 1 and 3 intervals contain lower concentrations of coarser-grained magnetic minerals with increasing influence of hematite and/or iron sulphide minerals. The HIZ interval is inferred to contain high occurrences of fine-grained bacterial magnetosomes. Based on geochemical proxies, East Sea conditions for the HIZ interval, coincident with the last glacial maximum (LGM), can be summarized as having low total organic carbon (TOC), enhanced eolian contributions from terrestrial organic particles and iron-bearing minerals under the influence of an intensified East Asian winter monsoon, along with iron-reducing, but not sulphidic, conditions that favoured growth and preservation of magnetotactic bacteria. The delicate balance between reductive dissolution of magnetofossils under sulphidic conditions and production and preservation of magnetotactic bacteria in overlying iron-reducing sediments for the HIZ interval is responsible for the resultant abundance variations of magnetosomes in the studied sediments. [ABSTRACT FROM AUTHOR]

The use of the TEX 86 temperature proxy has thus far come to differing results as to whether TEX 86 temperatures are representative of surface or subsurface conditions. In addition, although TEX 86 temperatures might reflect sea surface temperatures based on core-top (Holocene) values, this relationship might not hold further back in time. Here, we investigate the TEX 86 temperature proxy by comparing TEX 86 temperatures to Mg/Ca temperatures of multiple species of planktonic foraminifera for two sites in the eastern tropical Pacific (on the Cocos and Carnegie Ridges) across the Holocene and Last Glacial Maximum. Core-top and Holocene TEX 86 H temperatures at both study regions agree well, within error, with the Mg/Ca temperatures of Globigerinoides ruber , a surface dwelling planktonic foraminifera. However, during the Last Glacial Maximum, TEX 86 H temperatures are more representative of upper thermocline temperatures, and are offset from G. ruber Mg/Ca temperatures by 5.8 °C and 2.9 °C on the Cocos Ridge and Carnegie Ridge, respectively. This offset between proxies cannot be reconciled by using different TEX 86 temperature calibrations, and instead, we suggest that the offset is due to a deeper export depth of GDGTs at the LGM. We also compare the degree of glacial cooling at both sites based on both temperature proxies, and find that TEX 86 H temperatures greatly overestimate glacial cooling, especially on the Cocos Ridge. This study has important implications for applying the TEX 86 paleothermometer in the eastern tropical Pacific. [ABSTRACT FROM AUTHOR]

Glacial landforms are well preserved on Taibai Mountain (3767 m), the main peak of the Qinling mountain range located south of the Loess Plateau and east of the Qinghai-Tibet Plateau. The timing and extent of Quaternary glaciation in the study area is important for reconstructing Quaternary environmental change however numerical ages for glaciation in this study area have not previously been well resolved. Using terrestrial in situ cosmogenic nuclides we dated four samples collected from two glacially eroded rock steps in the upper part of a valley near the main peak, in an area previously identified as having been occupied by ice during the Taibai glaciation. The 10 Be results are all late glacial in age: 18.6 ± 1.1 ka, 16.9 ± 1.0 ka, 16.9 ± 1.1 ka and 15.1 ± 1.0 ka. The spatial pattern of ages in the valley suggests fast retreat, with horizontal and vertical retreat rates estimated to be on the order of 0.4 and 0.09 m a −1 , respectively. A simple extrapolation of these retreat rates from the ages at the two sample sites suggests that the glacier retreat began during Last Glacial Maximum and that glaciers disappeared from the main peak by about 15 ka. [ABSTRACT FROM AUTHOR]

Brown bears are mostly found in relatively low densities in the mountainous forests of Iran, from north to northwest and west, as well. Phylogeographic and genetic relationships between Iranian brown bears and others in the world are still unclear. We sequenced a 614 bp fragment of mtDNA control region of 15 sampled brown bears throughout Iran, where a dataset comprising a total number of 336 sequences belonging to brown and polar bears was included in the analyses. As compared to other brown bears, the Iranian brown bear presents remarkable haplotype diversity (15 individuals, 12 new haplotypes). Phylogenetic analyses revealed one major previously uncharacterized mtDNA lineage within Iranian brown bears, comprising 2–3 subclades: (i) Northern Iran, which includes bears from the Alborz and the Iranian Caucasus Mountains; (ii) Western Iran, including the individuals from the Zagros Mountains; and (iii) Fars, which comprises bears living in the Southern Zagros Mountains. These subclades are found in different geographic locations in Iran, indicating pronounced current population structuring in females. Moreover, statistical analyses of fixation index ( F ST ) and analysis of molecular variance (AMOVA) demonstrate significant genetic structure among the subclades. Fu's F S test suggested that northern and western Iranian brown bears probably underwent a recent population expansion, indicating significant deviations from neutrality. Overall, these findings likely imply the survival of brown bears in several refugia during the last glacial maximum in (or near) Iran. [ABSTRACT FROM AUTHOR]

This study presents GIS-based estimates of permafrost extent in the northern circumpolar region during the Last Glacial Maximum (LGM), based on a review of previously published maps and compilations of field evidence in the form of ice-wedge pseudomorphs and relict sand wedges. We focus on field evidence localities in areas thought to have been located along the past southern border of permafrost. We present different reconstructions of permafrost extent, with areal estimates of exposed sea shelf, ice sheets and glaciers, to assess areas of minimum, likely and maximum permafrost extents. The GIS-based mapping of these empirical reconstructions allows us to estimate the likely area of northern permafrost during the LGM as 34.5 million km2 (which includes 4.7 million km2 of permafrost on exposed coastal sea shelves). The minimum estimate is 32.7 million km2 and the maximum estimate is 35.3 million km2. The extent of LGM permafrost is estimated to have been between c. 9.1 to 11.7 million km2 larger than its current extent on land (23.6 million km2). However, 2.4 million km2 of the lost land area currently remains as subsea permafrost on the submerged coastal shelves. The LGM permafrost extent in the northern circumpolar region during the LGM was therefore about 33 percent larger than at present. The net loss of northern permafrost since the LGM is due to its disappearance in large parts of Eurasia, which is not compensated for by gains in North America in areas formerly covered by the Laurentide ice sheet. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Motivated by indications from paleo-evidence, this paper investigates the changes of the Southern Westerly Winds (SWW) and westerly-wind stress between the Last Glacial Maximum (LGM) and pre-industrial in the PMIP3/CMIP5 simulations, highlighting the role of Antarctic sea ice in modulating the wind effect on ocean. Particularly, a de-correlation occurs between the changes in SWW and westerly-wind stress, caused primarily by an equatorward expansion of winter Antarctic sea ice that undermines the efficacy of wind in generating stress over the liquid ocean. Such de-correlation may reflect the LGM condition in reality, in view of the fact that the model which simulates this condition has most fidelity in simulating modern SWW and Antarctic sea ice. Therein two models stand out for their agreements with paleo-evidence regarding the change of SWW and the westerly-wind stress. They simulate strengthened and poleward-migrated LGM SWW in the atmosphere, consistent with the indications from dust records. Whilst in the ocean, they well capture an equatorward-shifted pattern of the observed oceanic front shift, with most pronounced equatorward-shifted westerly wind stress during the LGM. [ABSTRACT FROM AUTHOR]

To reconstruct the timing of Alpine glacier advances onto the Jura Mountains, we sampled 17 Alpine erratic boulders within and beyond the LGM (Last Glacial Maximum) extent of the Valais Glacier along three transect for the analysis of cosmogenic Be. Our results indicate at least two advances into the study area in Northwestern Switzerland; one during the LGM and one beforehand. Reaching of the maximum extent of by the Valais Glacier into the Jura mountains during the LGM occurred at 21.9 ± 1.8 ka based on erratic boulders exposure ages. Ages of boulders located beyond the LGM extent of the Valais Glacier vary from 19.9 ± 1.6 to 144.0 ± 9.6 ka. These ages indicate that many of the boulders were displaced and re-deposited by local ice in the Jura Mountains both during and perhaps even prior to the LGM. Therefore, the chronology of the pre-LGM advance(s) of Alpine glaciers into the Jura Mountains remains still to be elaborated. [ABSTRACT FROM AUTHOR]

This study presents a reconstruction of mean annual surface temperature in New Zealand over the last glacial period using groundwater noble gas paleothermometry. Low resolution 14 C-derived mean recharge ages of groundwater from the Deep Moutere, Deep Wairau, and Taranaki aquifers range from roughly 41,500 yr to present, including the last glacial maximum (LGM). Modeled noble gas temperatures of probable glacial-age samples range from roughly 3.7–6.2 °C cooler than present. We present an error-weighted mean cooling of 4.6 ± 0.5 °C relative to present during last glacial period. The screened depth intervals of some wells sampled in this study allow for a degree of mixing during extraction between groundwater layers of different recharge age. Mixing with modern groundwater may slightly elevate the noble gas temperatures (NGTs) of glacial-age samples while making them appear substantially younger. Given the uncertainty in dating, we cannot rule out a larger LGM temperature depression of up to ∼6 °C. The ∼4.6 °C cooling estimate agrees with a number of terrestrial paleoclimate reconstructions near the study area as well as the majority of nearby paleoceanographic temperature studies. [ABSTRACT FROM AUTHOR]

The Cuerpo de Hombre paleoglacier occupies the upper sector of the Cuerpo de Hombre river basin, located on the northwest slope of the Sierra de Béjar Mountains (Iberian Central System). At the stage of the maximum ice extent during the last glacial cycle, this paleoglacier was one of the longest tongues emerging from the Sierra de Béjar plateau glacier. The study of the morphostratigraphic succession and the geometric and genetic relations between the geomorphological indicators of this paleoglacier has revealed its evolutionary sequence during the last glacial cycle. The comparison between this sequence and the one previously established by a regional evolutionary pattern shows that although they both coincide in general terms, some stages/substages of this pattern must be corrected or more clearly defined. The absolute chronology of the different stages was obtained using terrestrial cosmogenic nuclides ( 10 Be). The maximum ice extent of Cuerpo de Hombre paleoglacier has been dated to ∼25.0 ka (MIS2 and concurrent with the LGM). This chronology coincides with date obtained for other paleoglaciers in the Iberian Central System, but is slightly more modern than the regional chronology estimated as most likely for the maximum ice extent in these areas. Subsequent to reaching the maximum extent, the glacier had a retreat (minimum age ∼20.6 ka), followed by another stage of expansion or readvance, after which it stabilised until the start of the deglaciation stage (∼17.8 ka). In all previous work, the deglaciation stages in the Iberian Central System have been described as one continuous recession process. However, in the Cuerpo de Hombre paleoglacier, all the data point to stabilisations of considerable magnitude, and particularly to another stage of readvance of the glacier. Based on its chronology (minimum age ∼11.1 ka) and its evolutionary significance, this new readvance has been correlated with the Older Dryas stadial. Finally, the evolutionary context marked by the indicators and its chronology confirm that the whole of the Late Glacial sequence identified in Cuerpo de Hombre can be correlated with the traditionally established in northern Europe (climatic periods or stadials and interstadials): Oldest Dryas-Bølling-Older Dryas-Allerød-Younger Dryas. The minimum ages obtained for the cold periods (stadials) in this sequence in the Cuerpo de Hombre paleoglacier are (respectively): ∼17.5 ka, ∼13.9 ka and ∼11.1 ka. This complete sequence of the Late Glacial Period, including the stadials Older and Younger Dryas, had not been previously identified in any of the paleoglaciers in the Iberian Central System. [ABSTRACT FROM AUTHOR]

Background and Aims: A worldwide increase in tree decline and mortality has been linked to climate change and, where these represent foundation species, this can have important implications for ecosystem functions. This study tests a combined approach of phylogeographic analysis and species distribution modelling to provide a climate change context for an observed decline in crown health and an increase in mortality in Eucalyptus wandoo, an endemic tree of south-western Australia. Methods: Phylogeographic analyses were undertaken using restriction fragment length polymorphism analysis of chloroplast DNA in 26 populations across the species distribution. Parsimony analysis of haplotype relationships was conducted, a haplotype network was prepared, and haplotype and nucleotide diversity were calculated. Species distribution modelling was undertaken using Maxent models based on extant species occurrences and projected to climate models of the last glacial maximum (LGM). Key Results: A structured pattern of diversity was identified, with the presence of two groups that followed a climatic gradient from mesic to semi-arid regions. Most populations were represented by a single haplotype, but many haplotypes were shared among populations, with some having widespread distributions. A putative refugial area with high haplotype diversity was identified at the centre of the species distribution. Species distribution modelling showed high climatic suitability at the LGM and high climatic stability in the central region where higher genetic diversity was found, and low suitability elsewhere, consistent with a pattern of range contraction. Conclusions: Combination of phylogeography and paleo-distribution modelling can provide an evolutionary context for climate-driven tree decline, as both can be used to cross-validate evidence for refugia and contraction under harsh climatic conditions. This approach identified a central refugial area in the test species E. wandoo, with more recent expansion into peripheral areas from where it had contracted at the LGM. This signature of contraction from lower rainfall areas is consistent with current observations of decline on the semi-arid margin of the range, and indicates low capacity to tolerate forecast climatic change. Identification of a paleo-historical context for current tree decline enables conservation interventions to focus on maintaining genetic diversity, which provides the evolutionary potential for adaptation to climate change. [ABSTRACT FROM AUTHOR]

A new high-resolution palynological record from the Sea of Galilee (Israel), roughly spanning the Last Glacial Maximum (LGM) obtained from a trench dug in the vicinity of the well-dated prehistoric site of Ohalo II (23–24 ka cal. BP) — combined with detailed litho-stratigraphic and magnetic susceptibility analyses — provides evidence of vegetation, lake levels and climate change in the northern Jordan Valley. The sequence begins with laminated marls of the last Lake Lisan high stand and ends with the near-shore deposits containing the prehistoric site. Palynologically, the early phase of the high stand (pollen zone 1) is characterised by high-AP (mainly Quercus ithaburensis), reflecting a relatively humid climate. During its later part (zone 2), the increase in Artemisia indicates a regional drying. Several fluctuations in lake levels and humidity are recorded (pollen zones 3–4) prior to human occupation at the prehistoric camp, during a renewed humid climate (pollen zone 5); in its early phase Quercus calliprinos spread again in the mountainous areas around the lake, while the maquis of the later phase was typified by the deciduous Q. ithaburensis. The fact that a variety of data sets were retrieved from the very same section renders their correlation and combined environmental interpretation reliable and unique for this time period in the southern Levant. The reconstructed palaeoenvironmental picture indicates a rather mild LGM in the northern Jordan Rift. Although there are 17 14C and U-Th dates from the studied section, dating inconsistencies prevent direct correlations between the observed regional fluctuations and global events. [ABSTRACT FROM AUTHOR]

We present a paleoenvironmental reconstruction for the mountain fringe between the South-Eastern Alps and the Northern Dinarides (NE-Italy/W-Slovenia) during the Last Glacial Maximum. We focused on a new sedimentary and paleoecological archive spanning the LGM acme, located in an aggrading, permanently flooded and ponded plain, dammed by an active fluvioglacial megafan. The ecosystem reconstruction, based on two high resolution pollen records, is supported by a rich plant macrofossil flora and constrained by a robust radiocarbon chronology between 26 and 22 cal ka BP. We show evidence for persistence of boreal trees and of different open boreal forest types throughout the LGM at the south-eastern mountain fringe of the Alps and the Northern Dinarides. Fire frequency is responsible for high, oscillating forest openness. The paleobotanical record is discussed in the light of the ecogeographic diversity of the region. A belt formed by Swiss stone pine, larch and dwarf mountain pine on limestone bedrock, and accompanied by Spruce in the floodplain, extended uphill, while proximal outwash plain supported Scots pine and dwarf mountain pine. These differences arise from groundwater regimes rather than from local climate variability. A steep moisture gradient from the semiarid pedoclimatic regime prevailing in the Adriatic alluvial plain to the forested mountain fringe is related to the orographic rainout triggered by southern air circulation. Mesophytic broad-leaved forest trees did not withstand the LGM temperature extremes in zonal ecosystems at the Alpine–Dinaric fringe; however, the fossil evidence suggests a number of microrefugia in karstic and thermal spring habitats of the northern Adriatic. [ABSTRACT FROM AUTHOR]

The Last Glacial Maximum (LGM) is widely used to refer to the episode when global ice volume last reached its maximum and associated sea levels were at their lowest. However, the boundaries of the interval are ill-defined and the term and acronym have no formal stratigraphical basis. This is despite a previous proposal to define it as a chronozone in the marine records on the basis of oxygen isotopes and sea levels, spanning the interval 23–19 or 24–18 ka and centred on 21 ka. In terrestrial records the LGM is poorly represented since many sequences show a diachronous response to global climate changes during the last glacial cycle. For example, glaciers and ice sheets reached their maximum extents at widely differing times in different places. In fact, most terrestrial records display spatial variation in response to global climate fluctuations, and changes recorded on land are often diachronous, asynchronous or both, leading to difficulties in global correlation. However, variations in the global hydrological system during glacial cycles are recorded by atmospheric dust flux and this provides a signal of terrestrial changes. Whilst regional dust accumulation is recorded in loess deposits, global dust flux is best recorded in high-resolution polar ice-core records, providing an opportunity to define the LGM on land and establish a clear stratigraphical basis for its definition. On this basis, one option is to define the global LGM as an event between the top (end) of Greenland Interstadial 3 and the base (onset) of Greenland Interstadial 2, spanning the interval 27.540–23.340 ka (Greenland Stadial 3). This corresponds closely to the peak dust concentration in both the Greenland and Antarctic ice cores and to records of the global sea-level minima. This suggests that this definition includes not just the coldest and driest part of the last glacial cycle but also the peak in global ice volume. The later part of the LGM event is marked by Heinrich Event 2, which reflects the onset of the collapse of the Laurentide at c. 24 ka, together with other ice sheets in the North Atlantic region. A longer and later span for the LGM may be desirable, although defining this in chronostratigraphical terms is problematic. Whichever formal definition is chosen, this requires the contribution of the wider Quaternary community. [ABSTRACT FROM AUTHOR]

We investigate the response of the atmospheric and land surface components of the CMIP5/AR5 Earth System model HadGEM2-ES to pre-industrial (PI: AD 1860) and last glacial maximum (LGM: 21 kyr) boundary conditions. HadGEM2-ES comprises atmosphere, ocean and sea-ice components which are interactively coupled to representations of the carbon cycle, aerosols including mineral dust and tropospheric chemistry. In this study, we focus on the atmosphere-only model HadGEM2-A coupled to terrestrial carbon cycle and aerosol models. This configuration is forced with monthly sea surface temperature and sea-ice fields from equivalent coupled simulations with an older version of the Hadley Centre model, HadCM3. HadGEM2-A simulates extreme cooling over northern continents and nearly complete die back of vegetation in Asia, giving a poor representation of the LGM environment compared with reconstructions of surface temperatures and biome distributions. The model also performs significantly worse for the LGM in comparison with its precursor AR4 model HadCM3M2. Detailed analysis shows that the major factor behind the vegetation die off in HadGEM2-A is a subtle change to the temperature dependence of leaf mortality within the phenology model of HadGEM2. This impacts on both snow-vegetation albedo and vegetation dynamics. A new set of parameters is tested for both the pre-industrial and LGM, showing much improved coverage of vegetation in both time periods, including an improved representation of the needle-leaf forest coverage in Siberia for the pre-industrial. The new parameters and the resulting changes in global vegetation distribution strongly impact the simulated loading of mineral dust, an important aerosol for the LGM. The climate response in an abrupt 4× pre-industrial CO simulation is also analysed and shows modest regional impacts on surface temperatures across the Boreal zone. [ABSTRACT FROM AUTHOR]

Pleistocene glaciations were among the important historic events that shaped the population structures of marine organisms. Genetic studies of different marine fauna and flora have demonstrated the effect of Pleistocene glaciations on taxa that reside in marginal seas. However, how marine island species responded to Pleistocene glaciations remains relatively unstudied, especially in Asia. Genetic analyses based on the island-associated barnacle Chthamalus moro collected from 14 sites in Asia reveal that C. moro comprises three distinct lineages, with COI divergence ranging from 3.9 to 8.3%. Population genetic analyses on respective lineages reveal signs of demographic expansion within the Pleistocene epoch at different times. The Ogasawara lineage, which has a more oceanic distribution, expanded the earliest, followed by the population expansion of the Ryukyu and Southern lineages that inhabit islands closer to the continent. The data suggest that the inhabitants of outer islands may have been less affected by Pleistocene glaciations than those that reside closer to the continent, as the former were able to maintain a large, stable, effective population size throughout the late Pleistocene. [ABSTRACT FROM AUTHOR]