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

Millennial-scale climate variations during the last glacial period, such as Dansgaard–Oeschger (DO) cycles and Heinrich events, have been extensively studied using ice core and marine proxy records. However, there is a limited understanding of the magnitude of these temperature fluctuations in continental regions, and questions remain about the seasonal signal of these climate events. This study presents a 60 000-year-long temperature reconstruction based on branched glycerol dialkyl glycerol tetraethers (brGDGTs) extracted from lake sediments from the Eifel Volcanic Field, Germany. brGDGTs are bacterial membrane-spanning lipids that are known to have a strong relationship with temperature, making them suitable for temperature reconstructions. We test several temperature calibration models on modern samples taken from soils and multiple maar lakes. We find a negative bias in brGDGT-based temperature estimates associated with water depth and anoxic conditions that can be corrected for by accounting for a brGDGT isomer that is only produced in anoxic conditions. The corrected temperature reconstruction correlates with proxy and climate model estimates of temperature spanning the same time period, validating the calibration approach we selected. However, millennial-scale variability is significantly dampened in the brGDGT record, and in contrast to other Northern Hemisphere climate records, during several Heinrich stadials, temperatures actually increase. We demonstrate that these apparent discrepancies can be explained by the unique seasonal response of the brGDGT paleothermometer to temperatures of months above freezing (TMAF). Our data support the view that warm-season temperatures in Europe varied minimally during the last glacial period and that abrupt millennial-scale events were defined by colder, longer winters. Our continuous high-resolution temperature reconstruction provides important information about the magnitude of seasonal climate variability during the last glacial period that can be used to test climate models and inform studies of paleoecological change. [ABSTRACT FROM AUTHOR]

To reconstruct the history of organic carbon (OC) aerosol over south‐eastern Europe, dissolved organic carbon (DOC) and its 14C signature (DO14C) were investigated along an ice core drilled at the Mount Elbrus (ELB) in Caucasus. In summer, compared to pre‐1945 levels, the DOC concentrations increased by 45% after 1960, the mean DO14C depletion in recent ELB ice relative to atmospheric 14CO2 of 32% being attributed to fossil‐fuel sources. DO14C content of ice deposited during the bomb‐peak era (1955–1980) closely followed atmospheric 14CO2 changes caused by atmospheric nuclear tests, suggesting the living biosphere as the main biogenic source of DOC in summer in this region. ELB data contrast with those previously obtained in summer Alpine (western Europe) ice in which a post‐1950 doubling of DOC was observed and attributed to enhanced emissions of organic compounds from vegetation in France. This regional difference is discussed with respect to changes of biogenic organic compound emissions in response to past change of use‐land and global warming. ELB data document, for the first time, changes of DOC and DO14C in winter mountain ice showing an increase by 44% of DOC levels associated with a 14C signature being 47% lower than that of atmospheric 14CO2 in ELB ice deposited after 1960. The 14C winter ELB ice record followed atmospheric 14CO2 changes with a delay of ∼3 years, suggesting that remaining emissions from the living biosphere, together with a small contribution from wood burning, are the main biogenic sources of DOC in winter in this region. Plain Language Summary: A good knowledge of past aerosol load and composition is important for climate change. In addition to sulfate, organic carbon aerosol (OC) is a major constituent of present‐day aerosol but its budget remains far less understood. Ice‐core chemical studies help to quantify natural versus anthropogenic sources over the past. Previous investigations of OC and its radiocarbon signature in Alpine ice had shown a doubling of summer OC due to enhanced emissions from vegetation contrasting with a weak impact of fossil‐fuel emissions in western Europe. The regional character of biogenic emissions motivated, however, further studies conducted in other regions. Investigations of OC and its radiocarbon signature in an ice core extracted in the Caucasus permitted to reconstruct past OC changes in the south‐eastern Europe. It is shown that, even in 1970, vegetation emissions still dominate fossil‐fuel emissions as source of OC in summer. A quite large temporal variability of OC is observed and attributed to variations of vegetation emissions in response to past fluctuations of summer temperature in this region. After 1960, fossil‐fuel emissions in winter became almost as large as biogenic emissions that were related to the living biosphere with a small contribution from wood burning at that season. Key Points: Biogenic sources dominate fossil‐fuel sources of present‐day summer organic carbon aerosol (70% vs. 30%) in south‐eastern EuropeLarge pre‐industrial variability of organic carbon aerosol in summer driven by vegetation emissions modulated by past temperaturesLiving biosphere with a small contribution from wood burning slightly exceeds present‐day fossil‐fuel sources of organic carbon in winter [ABSTRACT FROM AUTHOR]

Dansgaard‐Oeschger (D‐O) climate variability during the last glaciation was first evidenced in ice cores and marine sediments, and is also recorded in various terrestrial paleoclimate archives in Europe. The relative synchronicity across Greenland, the North Atlantic and Europe implies a tight and fast coupling between those regions, most probably effectuated by an atmospheric transmission mechanism. In this study, we investigated the atmospheric changes during Greenland interstadial (GI) and stadial (GS) phases based on regional climate model simulations using two specific periods, GI‐10 and GS‐9 both around 40 ka, as boundary conditions. Our simulations accurately capture the changes in temperature and precipitation as reconstructed by the available proxy data. Moreover, the simulations depict an intensified and southward shifted eddy‐driven jet during the stadial period. Ultimately, this affects the near‐surface circulation toward more southwesterly and cyclonic flow in western Europe during the stadial period, explaining much of the seasonal climate variability recorded by the proxy data, including oxygen isotopes, at the considered proxy sites. Plain Language Summary: The climate during the last ice age varied between colder and warmer periods on timescales ranging from hundreds to thousands of years. This variability was first detected in Greenland ice cores and marine sediment cores of the North Atlantic, as well as in continental geological records in Europe. The variation between the colder and warmer periods occur mostly simultaneously in Greenland and in Europe, which is why the atmosphere is assumed to have an important role in transferring the climate signals. We simulated two different periods of the last ice age, one colder and one warmer around 40,000 years ago, using a regional climate model. The aim was to study how the climate and atmospheric circulation changed during these two periods. We find the eddy‐driven jet over the North Atlantic intensified and shifted southward during the colder period. The jet influences the near‐surface atmospheric circulation and leads to more southwesterly and cyclonic flow in western Europe. Oxygen isotope variations observed in western European paleoclimate records may be partly explained by different, more southern moisture sources on top of changes in seasonal temperatures. Key Points: Simulated temperatures agree with proxy data; precipitation is biased but GI‐10 versus GS‐9 differences are well capturedThe stadial winter jet stream is intensified and shifted southward, consistent with dominant southwesterly/cyclonic flow in western EuropeOxygen isotope signal changes at western European proxy sites may be explained not only by temperature but also by varying moisture sources [ABSTRACT FROM AUTHOR]

Freshwater, in the form of terrestrial runoff, is hypothesized to have played a critical role in past centennial to millennial scale climate variability by suppressing the production of deep-water in the North Atlantic. It may also play a central role in future climate change as ice sheet and glacier melt accelerates under anthropogenic climate change. In model studies of both past and future climate change, freshwater Hosing (i.e. injection across wide bands in the North Atlantic) is typically used as a means-to-an-end by inducing a strong thermohaline circulation and climate response, with little regard for the other roles that freshwater plays in a complex coupled climate environment. Herein, we evaluate the realism of Hosing relative to two more sophisticated freshwater injection methods, all under glacial boundary conditions: regional injection (allowing the relatively coarse-resolution climate model to transport the freshwater) and a novel freshwater fingerprint method. The latter approach distributes freshwater into an eddy-parametrizing ocean model based upon where it is transported to in a higher resolution eddy-permitting model. Here the COSMOS Earth system model is used as the eddy-parametrizing model, and a configuration of the MITgcm model as the eddy-permitting model. This analysis address three primary questions. Firstly, where is freshwater routed at moderate versus eddy-permitting resolution? Secondly, does the freshwater fingerprint method allow the coarser resolution model to reproduce the net-results of eddy-permitting behaviour? Thirdly, how do climate impacts vary between different forms of freshwater injection? Of the four outlets tested, we find that freshwater released at the Mackenzie River (MAK) outlet results in the most similar freshwater transport patterns at both the eddy-parametrizing and the eddy-permitting resolutions. However at eddy-permitting resolution there is a greater freshening of the contemporary Labrador Sea deep water formation region and mixing of freshwater into the Icelandic Sea. Similarly, Fennoscandian (FEN) freshwater discharge at eddy-permitting resolution results in more freshening of the Greenland-Iceland-Norwegian (GIN) Seas. Freshwater released from within the Gulf of St. Lawrence (GSL) demonstrates large-scale differences between coarse-resolution versus eddy-permitting distributions over the whole North Atlantic. At eddy-permitting resolution, GSL-sourced freshwater freshens the North Atlantic (specifically deep water formation regions important during cold glacial periods) more effectively than at eddy-parametrizing resolution. In COSMOS, freshwater deposited into the GOM results in a larger salinity anomaly at sites of deep-water formation in the northern North Atlantic than freshwater deposited into the GSL, whereas this relationship is reversed in MITgcm. When instead the freshwater fingerprint method is used in COSMOS, the relative strengths of GOM and GSL salinity anomalies in this deep-water formation region align with the eddy-permitting responses. However, for all injection locations considered, the pattern of MITgcm salinity anomalies are best matched by the COSMOS regional injection simulations and not the fingerprint injection simulations. Hosing the North Atlantic in COSMOS results in stronger and earlier sea ice growth and surface cooling versus either regional injection or the fingerprint methods. Comparing regional injections to their respective fingerprint counterparts, injecting freshwater at the outlets results in earlier, but not faster, climate changes in the GIN Seas, mainland Europe, and GRIP ice core regions for the MAK and FEN regions relative to the fingerprint methods. For these injections, regional simulations show both a stronger and faster initial AMOC reduction than the fingerprint simulations. In short, for at least the COSMOS model, both the hosing and fingerprint methodologies are inferior to regional injection when considering salinity distributions alone but when considering AMOC and freshening of deep-water formation regions the fingerprint method corrects the response of the GSL and GOM outlets. [ABSTRACT FROM AUTHOR]

This visual essay presents drawings related to a research project that sought to develop a visual language that communicates the precarity of clothing items that have emerged from alpine glaciers in Europe. These artworks achieve a poetic effect that recalls the tensions and challenges of preserving these artifacts of glacial archaeology. This essay focuses on selected drawings of footwear from the exhibition Emergency! at Drawing Projects UK (November 10, 2022–February 4, 2023) and articulates how drawing was used as a form of touching to imaginatively translate the experience of encountering these items of footwear into artworks. The artworks offer an example of how artistic engagement with museum collections can generate a creative response to traces of the past and invite reflection on the future of our planet. [ABSTRACT FROM AUTHOR]

Millennial-scale climate variations during the last glacial period, such as Dansgaard–Oeschger (D/O) cycles and Heinrich events, have been extensively studied using ice core and marine proxy records. However, there is a limited understanding of the magnitude of these temperature fluctuations in continental regions, and questions remain about the seasonal signal of these climate events. This study presents a 60,000-year long temperature reconstruction based on branched glycerol dialkyl glycerol tetraethers (brGDGTs) extracted from lake sediments from the Eifel volcanic field, Germany. brGDGTs are bacterial membrane lipids that are known to have strong relationship with temperature, making them suitable for temperature reconstructions. We test several temperature calibration models on modern samples taken from soils and multiple maar lakes. We find a bias associated with water depth and anoxic conditions that can be corrected for by accounting for a brGDGT isomer that is only produced in anoxic conditions. The corrected temperature reconstruction correlates with proxy and model temperature record spanning the same time period, validating the calibration model. However, millennial-scale variability is significantly dampened in the brGDGT record, and in contrast to other northern hemisphere climate records, during several Heinrich stadials, temperatures actually increase. We demonstrate that these apparent discrepancies can be explained by the unique seasonal response of the brGDGT paleothermometer to temperatures of months above freezing (TMAF). Our data support the view that warm season temperatures in Europe varied minimally during the last glacial period, and that abrupt millennial-scale events were defined by colder, longer winters. Our continuous high-resolution temperature reconstruction provides important information about the magnitude of seasonal climate variability during the last glacial period that can be used to test climate models and inform studies of paleoecological change. [ABSTRACT FROM AUTHOR]

Individual high-Alpine ice cores have been proven to contain a well-preserved history of past anthropogenic air pollution in western Europe. The question of how representative one ice core is with respect to the reconstruction of atmospheric composition in the source region has not been addressed so far. Here, we present the first study systematically comparing longer-term ice-core records (1750–2015 CE) of various anthropogenic compounds, such as major inorganic aerosol constituents (NH4+ , NO3- , SO42-), black carbon (BC), and trace species (Cd , F- , Pb). Depending on the data availability for the different air pollutants, up to five ice cores from four high-Alpine sites located in the European Alps analysed by different laboratories were considered. Whereas absolute concentration levels can partly differ depending on the prevailing seasonal distribution of accumulated precipitation, all seven investigated anthropogenic compounds are in excellent agreement between the various sites for their respective, species-dependent longer-term concentration trends. This is related to common source regions of air pollution impacting the four sites less than 100 km away including western European countries surrounding the Alps. For individual compounds, the Alpine ice-core composites developed in this study allowed us to precisely time the onset of pollution caused by industrialization in western Europe. Extensive emissions from coal combustion and agriculture lead to an exceeding of pre-industrial (1750–1850) concentration levels already at the end of the 19th century for BC, Pb , exSO42- (non-dust, non-sea salt SO42-), and NH4+ , respectively. However, Cd , F- , and NO3- concentrations started surpassing pre-industrial values only in the 20th century, predominantly due to pollution from zinc and aluminium smelters and traffic. The observed maxima of BC, Cd , F- , Pb , and exSO42- concentrations in the 20th century and a significant decline afterwards clearly reveal the efficiency of air pollution control measures such as the desulfurization of coal, the introduction of filters and scrubbers in power plants and metal smelters, and the ban of leaded gasoline improving the air quality in western Europe. In contrast, NO3- and NH4+ concentration records show levels in the beginning of the 21th century which are unprecedented in the context of the past 250 years, indicating that the introduced abatement measures to reduce these pollutants were insufficient to have a major effect at high altitudes in western Europe. Only four ice-core composite records (BC, F- , Pb , exSO42-) of the seven investigated pollutants correspond well with modelled trends, suggesting inaccuracies of the emission estimates or an incomplete representation of chemical reaction mechanisms in the models for the other pollutants. Our results demonstrate that individual ice-core records from different sites in the European Alps generally provide a spatially representative signal of anthropogenic air pollution trends in western European countries. [ABSTRACT FROM AUTHOR]

Emission inventories indicate that thallium, a highly toxic metal, is emitted during coal burning and cement production. These estimates have been established only for the 1980s and 1990s but up to now they have not been compared to long‐term observations. Here we used alpine ice cores to document thallium pollution over Europe since ∼1850. Ice‐core thallium concentrations increased from 1890 to 1910, and decreased after 1965 to concentrations that were half 1890 levels. Comparison of ice‐core trends, estimated past emissions, and state‐of‐the‐art atmospheric aerosol transport modeling suggest that coal burning was responsible for thallium pollution in Europe, particularly from 1920 to 1965 because of high coal consumption at that time. The subsequent decline resulted from decreased coal consumption and reduced emissions following technological improvements. The ice‐core data suggest that the rapid growth of cement production that took place in Europe after 1950 had a limited impact on thallium pollution. Plain Language Summary: Although less prevalent in the environment than toxic metals such as lead and cadmium, thallium is a highly toxic metal even at very low levels. Because reliable measurements are difficult at such low concentrations, thallium pollution is far less documented than other toxic metals. Cement production originally was estimated to be the primary source of thallium pollution at the global scale, but it was later recognized that coal burning was likely the main source. These previous estimates refer to the recent decades but no longer‐term inventories were available. Furthermore, no inventories were established at the scale of the European continent. Detailed measurements in Alpine ice cores show that thallium pollution after the late 19th century primarily was the result of coal burning in western Europe, and was largest between 1920 and 1965 as expected from coal consumption records. The rapid growth of cement production that took place after World War II had only limited impact on thallium pollution in Europe. Key Points: Alpine ice core data indicate thallium pollution in western Europe since ∼1850Emissions from growing cement production after World War II contributed little to European thallium pollutionAnthropogenic thallium emissions in western Europe were dominated by coal burning throughout the 20th century [ABSTRACT FROM AUTHOR]

Information about past ecosystem dynamics and human activities is stored in the ice of Colle Gnifetti glacier in the Swiss Alps. Adverse climatic intervals incurred crop failures and famines and triggered reestablishment of forest vegetation but also societal resilience through innovation. Historical documents and lake sediments record these changes at local—regional scales but often struggle to comprehensively document continental‐scale impacts on ecosystems. Here, we provide unique multiproxy evidence of broad‐scale ecosystem, land use, and climate dynamics over the past millennium from a Colle Gnifetti microfossil and oxygen isotope record. Microfossil data indicate that before 1750 CE forests and fallow land rapidly replaced crop cultivation during historically documented societal crises caused by climate shifts and epidemics. Subsequently, with technology and the introduction of more resilient crops, European societies adapted to the Little Ice Age cold period, but resource overexploitation and industrialization led to new regional to global‐scale environmental challenges. Plain Language Summary: Sophisticated microscopy and geochemistry analyses of glacier ice from the Monte Rosa Massif in the Swiss Alps reveal close linkages among European climate, vegetation, agriculture, pollution, pests, and fire during the past millennium. Our novel time series shows that societal and environmental dynamics were mainly controlled by climate, pandemics, and technological innovations. By placing the glacial information into historical context, we reveal some of the mechanisms that created prosperity and peril in Europe's past. Industrialization and import of maize and other new crops enabled European societies to transcend the crop failures and famines of the Little Ice Age climate period during the 19th century, but unintended environmental consequences resulted, which are now culminating in global warming and species loss. Key Points: Novel ice core microfossil data reveal large‐scale dynamics among ecosystems, land use, and climate in EuropeProxies preserved in ice cores link land‐use change to societal challenges caused by climate events and epidemicsAgricultural reforms and industrialization disrupted links between climate and land use and led to current environmental challenges [ABSTRACT FROM AUTHOR]

The H1N1 "Spanish influenza" pandemic of 1918–1919 caused the highest known number of deaths recorded for a single pandemic in human history. Several theories have been offered to explain the virulence and spread of the disease, but the environmental context remains underexamined. In this study, we present a new environmental record from a European, Alpine ice core, showing a significant climate anomaly that affected the continent from 1914 to 1919. Incessant torrential rain and declining temperatures increased casualties in the battlefields of World War I (WWI), setting the stage for the spread of the pandemic at the end of the conflict. Multiple independent records of temperature, precipitation, and mortality corroborate these findings. Plain Language Summary: A new, high‐resolution climate record from Europe shows a once‐in‐a‐century climate anomaly that occurred during the years of World War I and the Spanish flu pandemic. Mortality data from all causes show increases in times of worsening weather, precipitation, and temperatures, a factor in many of the major battles of WWI, as well as a possible exacerbating factor for the virulence of the pandemic. Key Points: Novel, high‐resolution climate record from Europe shows strong influx of marine air in a 1914–1918 climate anomaly unmatched in 100 yearsIndependent precipitation, temperature, and historical records corroborate the timing and extent of the anomalyHistorical and epidemiological records indicate that this climate anomaly affected the mortality in WWI as well as the "Spanish flu" pandemic [ABSTRACT FROM AUTHOR]

The climate of east-central Europe (ECE) is the result of a combination of influences originating in the wider North Atlantic realm, the Mediterranean Sea, and the western Asian and Siberian regions. Previous studies have shown that the complex interplay between the large-scale atmospheric patterns across the region results in strongly dissimilar summer and winter conditions on timescales ranging from decades to millennia. To put these into a wider context, long-term climate reconstructions are required, but, largely due to historical reasons, these are lacking in ECE. We address these issues by presenting a high-resolution, radiocarbon-dated record of summer temperature variations during the last millennium in ECE, based on stable isotope analysis of a 4.84 m long ice core extracted from Focul Viu Ice Cave (Western Carpathians, Romania). Comparisons with both instrumental and proxy-based data indicate that the stable isotope composition of cave ice records the changes in summer air temperature and has a similar temporal evolution to that of the Atlantic Multidecadal Oscillation on decadal to multidecadal timescales, suggesting that changes in the North Atlantic are transferred, likely via atmospheric processes towards the wider Northern Hemisphere. On centennial timescales, the data show little summer temperature differences between the Medieval Warm Period (MWP) and the Little Ice Age (LIA) in eastern Europe. These findings are contrary to those that show a marked contrast between the two periods in terms of both winter and annual air temperatures, suggesting that cooling during the LIA was primarily the result of wintertime climatic changes. [ABSTRACT FROM AUTHOR]

Ravine slopes at the recently discovered Nesseltalgraben site in southeastern Germany provide a unique last glacial sediment record for the Northern Calcareous Alps. The 21 m-long profile is dominated by fine-grained lacustrine-palustrine sediments overlain by several metres of glacifluvial gravels and lodgement tills of the Last Glacial Maximum and underlain by a diamicton. The age model includes 29 radiocarbon analyses and one paleomagnetic anomaly (Laschamp event) together providing a modelled age range from c. 59 to 29.6 ka cal BP, i.e. Marine Isotope Stage (MIS) 3. Apart from a description of the lithofacies, X-ray-fluorescence (XRF) scanning and elemental analyses provide high-resolution records of the geochemical composition. Multivariate analyses of XRF data separate Ca from other major elements. Carbonate contents, represented by Ca and total inorganic carbon, reach maxima in repeatedly occurring calcareous silty to sandy layers and are related to glacigenic origin. These indicate repeated inner-alpine local glaciations during stadials of MIS 3. Scanning electron microscopy and XRF data confirm the detrital origin of these layers. In contrast, organic matter and elements more resistant to chemical weathering (Si, Ti, Zr) accumulated during interstadials and concurrently elevated Rb/Sr ratios indicate intensified weathering. The high-frequency proxy variations determined for Nesseltalgraben reflect interstadial-stadial climate variability comparable with oxygen-isotope records from Greenland ice cores and Alpine speleothems. Thus, Nesseltalgraben is among the very few independently dated sediment records from continental Europe covering the entire MIS 3 and reflecting the full Dansgaard-Oeschger climate variability. • A 21 m sediment profile from the northern Alps provides a complete MIS 3 record. • Repeated inner Alpine glaciations are indicated by calcareous silt layers. • Geochemical variations reflect interstadials and stadials. • The Nesseltalgraben record resembles Dansgaard-Oeschger climate variability. [ABSTRACT FROM AUTHOR]

Despite the fact that the Little Ice Age (LIA) is well documented for the European Alps, substantial uncertainties concerning the regional spatio-temporal patterns of temperature changes associated with the LIA still exist, especially for their eastern sector. Here we present a high-resolution (4–10 years) 700-year long mean July air temperature reconstruction based on subfossil chironomid assemblages from a remote lake in the Austrian Eastern Alps to gain further insights into the LIA climatic deterioration in the region. The record provides evidence for a prolonged period of predominantly cooler conditions during AD 1530–1920, broadly equivalent to the climatically defined LIA in Europe. The main LIA phase appears to have consisted of two cold time intervals divided by slightly warmer episodes in the second half of the 1600s. The most severe cooling occurred during the eighteenth century. The LIA temperature minimum about 1.5 °C below the long-term mean recorded in the mid-1780 s coincides with the strongest volcanic signal found in the Greenland ice cores over the past 700 years and may be, at least in part, a manifestation of cooling that followed the long-lasting AD 1783–1784 Laki eruption. A continuous warming trend is evident since ca AD 1890 (1.1 °C in 120 years). The chironomid-inferred temperatures show a clear correlation with the instrumental data and reveal a close agreement with paleotemperature evidence from regional high-elevation tree-ring chronologies. A considerable amount of the variability in the temperature record may be linked to changes in the North Atlantic Oscillation. [ABSTRACT FROM AUTHOR]

Abstract According to the findings of a complex radiocarbon dated sedimentological, geochemical, anthracological, phytolite, malacological study implemented on an open 1036 cm wind-blown sand, loess, sandy loess and fossil soils profile of western part of brickyard at Katymár village in Hungary. Increased boreal mixed-leaved forest steppe and temperate grassland cover characterized the interstadials in the SE Great Hungarian Plain during the terminal phase of MIS3 stage and MIS2 stage. These interstadials correlate well with the Dansgaard-Oeschger (DO) interstadials 8, 7, 6, 5, 4, 3, 2 and the post LGM warm interval (DO1) seen in the Greenland ice core oxygen isotope records. Intervening cold phases, on the other hand, their start correlating with Heinrich event 1, 2, 3, 4 and the LGM. These data overall confirm that millennial scale climate variability during MIS3 and MIS2 stages had profound effect on the terrestrial ecosystems in the continental interior of SE Europe leading to periodic mixed-leaved boreal forest steppe within mosaic structure expansions in the interstadias and cold steppe, taiga and tundra like spots mosaic and mixed vegetation expansion in the stadial phases. 1400–1500 year long drier interstadial and humid, extended vegetation covered stadial periods interchanged at Katymár sequence, therefore the vegetation and fauna development was different from the Atlantic and Central European schemes and inferred an independent local and regional South Carpathian Basin trend. [ABSTRACT FROM AUTHOR]

Marine isotope stage 3 (MIS 3) was characterised by marked oscillations of extreme cold episodes with very short warm events during the stadial, and several regional differences have been recorded in the ice cores and marine deposits. The aim of this study is to reconstruct this period by evaluating both terrestrial and regional responses. Cova del Coll Verdaguer, a site located on the Iberian Peninsula, preserves a sedimentary deposit dated to between 34 and 56 ka BP and provides an opportunity for evaluating the impact of climate changes on the regional landmass during a period that coincided with the last Neanderthal population on the Iberian Peninsula. Several dating methods, including U-series, electron spin resonance, amino acid racemization and radiocarbon (14C), were applied to the site and the ages obtained show good agreement. The biotic evidence obtained is substantial, comprising floristic data from palynology and charcoal analysis, and faunal data from large and small mammals, birds and gastropods. Environmental reconstruction points to an initially open meadow landscape at the base of the sequence (∼56 ka) that progressively changes to a woodland environment dominated by conifers (∼34 ka). The presence of few thermophilous taxa, in contrast with lower latitudes of the Iberian Peninsula, is also detected. The environmental conditions of mid-altitude, Mediterranean, limestone mountains for the last Neanderthal populations appear to have been dominated by a forested landscape comprising boreal or mixed coniferous forest, characterised by a low usable biomass with poor comestible plant resources and dispersed herbivore populations. [ABSTRACT FROM AUTHOR]

The longest six instrumental temperature records of monthly means reach back maximally to 1757AD and were recorded in Europe. All six show a V-shape, with temperature drop in the 19th and rise in the 20th century. Proxy temperature time series of Antarctic ice cores show this same characteristic shape, indicating this pattern as a global phenomenon. We used the mean of the six instrumental records for analysis by discrete Fourier transform (DFT), wavelets, and the detrended fluctuation analysis (DFA). For comparison, a stalagmite record was also analyzed by DFT. The harmonic decomposition of the abovementioned mean shows only six significant frequencies above periods over 30 yr. The Pearson correlation between the mean, smoothed by a 15-yr running average (boxcar) and the reconstruction using the six significant frequencies, yields r = 0.961. This good agreement has a > 99.9% confidence level confirmed by Monte Carlo simulations. It shows that the climate dynamics is governed at present by periodic oscillations. We find indications that observed periodicities result from intrinsic dynamics. [ABSTRACT FROM AUTHOR]

Abstract: This report presents a study of the variability in a recently published April to September gridded reconstruction temperatures in Europe and an analysis of their extremes. This reconstruction was based on tree rings, historical documents, pollen assemblages and ice cores. The methodology used, an original spectral analog method, preserves long-term variations and the variability of temperature series, which guarantees the pertinence of the analysis of the extremes over a period as long as the last millennium. The analysis of the extremes was performed with the peak-over-threshold (POT) method over two warm periods (A.D. 1000–1350 and 1880–2007) and a cold period (A.D. 1350–1950). We found that (1) according to the long-term variations shown in this reconstruction, the growing season temperature during the last decade has exceeded all of those observed during the Medieval period; (2) the return period of the maximum event of the Medieval period has been reduced by at least a factor of 5; and (3) all decades before A.D. 1350 were warm on average but relatively heterogeneous, while the last decade was homogeneously warmer. A new result of this study concerning Europe is that this anthropogenic change is characterized by spatial homogeneity, with similar changes in both average temperatures and in the distribution of extreme events, while natural climate forcings induce warm periods with heterogeneous spatial patterns and less frequent extreme events. [Copyright &y& Elsevier]

Evidence of millennial-scale cold events following the last interglacial are well preserved in North Atlantic marine cores, Greenland ice, and pollen records from Europe. However, their timing was previously undetermined by radiometric dating. We report the first precise radiometric ages for two such events, C23 (105.1 ± 0.9 ka to 102.6 ± 0.8 ka) and C24 (112.0 ± 0.8 ka and 108.8 ± 1.0 ka), based on stable carbon and oxygen isotope measurements on a stalagmite from Italy (CC28). In addition to providing new information on the duration of these events in southern Europe, the age data provide invaluable tuning points for the Mélisey I (C24) and Montaigu (C23) pollen zones identified in western Europe. The former event is of particular significance because it represents the end of the Eemian interglacial forest phase in western Europe. The new age data will also allow fine tuning of the timing and duration of Greenland stadial 24 (equivalent to C23) in the North Greenland Ice Core Project ice core and, via a common gas-age chronology, tuning of the Vostok and EPICA (European Project for Ice Coring in Antarctica) ice cores. [ABSTRACT FROM AUTHOR]

129I in the European environment originates predominantly from the industrial nuclear fuel reprocessing plants Sellafield (Great Britain), Marcoule, and La Hague (both France). While reliable data on 129I releases from La Hague exist for the whole period of operation, less is known about the contributions from Sellafield and Marcoule. For those periods where no data are available, i.e., for the first 16 years of the Sellafield operation and for the first 3 decades of the Marcoule operation, we estimated releases into the atmosphere of 118 GBq and 825 GBq, respectively. Hence, Marcoule was the major European source of airborne 129I contributing about 45% to the total airborne 129I releases from all the European reprocessing facilities, until itwas decommissioned in 1997. The estimated total emissions were compared with 129I deposition fluxes for the time period 1970-2002, obtained from the analysis of an ice core from Fiescherhorn glacier, Swiss Alps (46°33'N, 08°04'E; 3900 m asl). The temporal evolution of the 129I deposition agrees well with the total 129I releases into the atmosphere from the European reprocessing facilities and from atmospheric nuclear weapons tests, supporting our estimated release rates. However, the 129I concentrations and deposition fluxes at Fiescherhorn glacier were a factor of 6 lower than values obtained from the analysis of rainwater collected near Zurich (408 m asl) in Switzerland in the years 1994-97. This suggests a strong vertical concentration gradient of 129I typical for water-soluble atmospheric trace species which are removed from the atmosphere in the course of days by precipitation scavenging, and must be taken into account if glaciers are used as an archive for a retrospective quantification of 129I deposition fluxes. In addition, the temporal evolution of the contribution of 129I re-emitted from the ocean's surface for the 129I inventory in the atmosphere was quantified for the first time. Although the annual amount of 129I released this way was very low until the early 1990s, it is similar to the airborne 129I releases from sellafield and La Hague in the present time. [ABSTRACT FROM AUTHOR]

Abstract: Typical rapid climate events punctuating the last glacial period in Greenland, Europe and Antarctica are compared to two rapid events occurring under warmer conditions: (i) Dansgaard–Oeschger event 25, the first abrupt warming occurring during last glacial inception; (ii) 8.2 ka BP event, the only rapid cooling recorded during the Holocene in Greenland ice cores and in Ammersee, Germany. The rate of warming during previous warmer interglacial periods is estimated from polar ice cores to 1.5 °C per millennium, without abrupt changes. Climate change expected for the 21st century should however be at least 10 times faster. To cite this article: V. Masson-Delmotte et al., C. R. Geoscience 337 (2005). [Copyright &y& Elsevier]

European paleoenvironmental records through the Last Glacial-Interglacial Transition (LGIT; ca 16-8 cal ka BP) record a series of climatic events occurring over decadal to multi-centennial timescales. Changes in components of the climatic system other than temperature (e.g. hydrology) through the LGIT are relatively poorly understood however, and further records of hydroclimatic changes are required in order to develop a more complete understanding on the phasing of environmental and anthropogenic responses in Europe to abrupt climate change. Here, we present a multiproxy palaeoenvironmental record (macroscale and microscale sedimentology, macrofossils, and carbonate stable isotopes) from a palaeolake sequence in the Vale of Pickering (VoP), NE England, which enables the reconstruction of hydroclimatic changes constrained by a radiocarbon-based chronology. Relative lake-level changes in the VoP occurred in close association (although not necessarily in phase) to threshold shifts across abrupt climate change transitions, most notably lowering during cooling intervals of the LGIT (∼GI-1d, ∼GI-1b, and ∼GS-1). This reflects more arid hydroclimates associated with these cooling episodes in the British Isles. Comparisons to hydrological records elsewhere in Europe show a latitudinal bifurcation, with Northern Europe (50–60°N) becoming more arid (humid), and Southern Europe (40–50°N) becoming more humid (arid) in response to these cooling (warming) intervals. We attribute these bifurcating signals to the relative positions of the Atlantic storm tracks, sea-ice margin, and North Atlantic Polar Front (NAPF) during the climatic events of the LGIT. • Lake-level reconstructions can be used to reconstruct hydroclimatic changes. • Northern (Southern) Europe becomes more arid (humid) during abrupt cooling events. • European hydroclimatic changes were more dynamic than changes in temperature. • Hydroclimatic changes were not concurrent with δ18O in the Greenland ice cores. [ABSTRACT FROM AUTHOR]

Because few ice core records from the Himalayas exist, understanding of the onset and timing of the human impact on the atmosphere of the "roof of the world" remains poorly constrained. We report a continuous 500-y trace metal ice core record from the Dasuopu glacier (7,200 m, central Himalayas), the highest drilling site on Earth. We show that an early contamination from toxic trace metals, particularly Cd, Cr, Mo, Ni, Sb, and Zn, emerged at high elevation in the Himalayas at the onset of the European Industrial Revolution (∼1780 AD). This was amplified by the intensification of the snow accumulation (+50% at Dasuopu) likely linked to the meridional displacement of the winter westerlies from 1810 until 1880 AD. During this period, the flux and crustal enrichment factors of the toxic trace metals were augmented by factors of 2 to 4 and 2 to 6, respectively. We suggest this contamination was the consequence of the long-range transport and wet deposition of fly ash from the combustion of coal (likely from Western Europe where it was almost entirely produced and used during the 19th century) with a possible contribution from the synchronous increase in biomass burning emissions from deforestation in the Northern Hemisphere. The snow accumulation decreased and dry winters were reestablished in Dasuopu after 1880 AD when lower than expected toxic metal levels were recorded. This indicates that contamination on the top of the Himalayas depended primarily on multidecadal changes in atmospheric circulation and secondarily on variations in emission sources during the last 200 y., Competing Interests: The authors declare no competing interest.

This paper compares lithic and faunal assemblages from Milovice (Czech Republic) and Kraków Spadzista (Poland) archaeological sites, with the aim of reconstructing temporal variations and patterning in Gravettian hunting of Mammuthus primigenius (woolly mammoth) in Central Europe. Milovice I was occupied ∼1 ky earlier than Kraków Spadzista, and is contemporaneous with Willendorf-Kostienkan sites. It is dated between 30.1 and 29.2 ka cal BP, overlapping the end of the GS 5.1 stadial in the Greenland ice core paleoclimatic record; the site was formed during cold climatic conditions. Radiocarbon dates from Kraków Spadzista indicate the site was occupied between 28.6 and 27 ka cal BP, spanning periods of significant climate instability through the GI 4 interstadial, GS 4 stadial, and the short interstadial GI 3. The two sites have fundamental differences in armature tool kits, such as raw materials and tool sizes. The hunter-gatherers at both sites had a mammoth-hunting focus, although they used different sized lithic weapon tips for hunting and thus probably had different strategies for procuring prey. The mammoth mortality profiles are significantly different at the two sites. At Milovice I, mid-life adults dominate the profile, while juveniles greatly dominate at Kraków Spadzista. We suggest that climatically mediated differences in mammoth migratory behavior, feeding behavior, population sizes, and demography influenced Gravettian people to manufacture and use different sizes of projectile points and to significantly increase the number of tool types during the most climatically unstable periods; these changes reflected tactical changes in Late Gravettian subsistence hunting in East-Central Europe. • Hunter-gatherers at Milovice I and Kraków Spadzista killed mammoths using different sizes and types of lithic weapon tips. • Climatic conditions and changes observed in lithic toolkits are clues about Late Gravettian mammoth-hunting practices in East-Central Europe. • Changes in mammoth demography, behavior, and ecology influenced human choices of sites, hunting strategies, and weaponry. [ABSTRACT FROM AUTHOR]

The article reports on the move of the U.S. and European researchers in seeking fundings for the chilly storage facilities of ice cores that are used to study the past climate of the Earth. According to the article, the cylindrical ice cores, which is drilled at multi-million-dollar expense from polar and glacial ice, can be kilometers long. It contains tiny bubble of trapped air that allows scientists to measure the concentration of carbon dioxide in the atmosphere from hundreds of thousands of years ago.