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At present, the Mediterranean is connected to the Atlantic Ocean through the narrow Strait of Gibraltar (only 13 km wide). The latter, in the late Miocene, most probably did not exist, and the Mediterranean – Atlantic water exchange took place through the Betic (Southern Spain) and Rifian (Northern Morocco) corridors. Studying the evolution of such gateways is fundamental when investigating the extraordinary event known as the Messinian Salinity Crisis (5.96 – 5.33 Ma), when the connection between the Mediterranean Sea and Atlantic Ocean significantly diminished or even ceased. In this work we present a new high resolution geochemical (XRF and stable isotope) record of the Tortonian – Messinian interval of the Montemayor-1 and Huelva-1 cores located in the Betic corridor, current Guadalquivir Basin. Our new data enabled in the first place the high-resolution tuning of the 7.4 – 5.8 Ma time interval, and consequently to precisely date environmental changes and relate them to Mediterranean and global events.Our results indicate that, at 7.17 Ma and in concomitance with a shallowing of the basin, the bottom water residence time, temperature and salinity increased. These changes have been associated with a reduction of the Mediterranean Outflow Water reaching the Guadalquivir Basin as a consequence of the restriction of the last strand of the Betic corridor connecting the Mediterranean and the Atlantic. This hypothesis is in line with the analogous changes observed in several Mediterranean Sea locations, where from 7.17 Ma a reduced Mediterranean – Atlantic connection is visible. Nonetheless, even if such reduction of the connection was feasible, the same changes in isotope record and analogous cyclicity observed both in the Guadalquivir and Alboran Basin record imply that the Mediterranean signal was still reaching the Betic gateway to some degree. In addition, the significant offset present between our and North Atlantic oxygen stable isotope records entails how the signal in the Guadalquivir basin could not have been purely Atlantic. Consequently, we conclude that a significant Mediterranean signal was still present in the Betic corridor during the Messinian.

Antequera in southern Spain is widely recognised as an outstanding example of the European megalithic phe- nomenon. One of its most remarkable features is the evident relationship between conspicuous natural for- mations and human-built monuments. Here, the authors report the results of their investigation of a tomb newly discovered at the site of Piedras Blancas at the foot of La Peña de los Enamorados, a limestone massif that dominates the Antequera plain. Excavation and multidisciplinary study, including geological, architectural and archaeoastronomical investigations, have revealed a complex funerary monument that is part natural, part built, part hypogeum, part megalith. The results emphasise the centrality of La Peña in the Neolithic worldview and encourage wider investigation of prehistoric place-making.

Antarctic sea-ice extent, primary productivity and ocean circulation represent interconnected systems that form important components of the global carbon cycle. Subdecadal to centennial-scale variability can influence the characteristics and interactions of these systems, but observational records are too short to evaluate the impacts of this variability over longer timescales. Here, we use a 170-m-long sediment core collected from Integrated Ocean Drilling Program Site U1357B, offshore Adélie Land, East Antarctica to disentangle the impacts of sea ice and subdecadal climate variability on phytoplankton bloom frequency over the last ~11,400 years. We apply X-ray computed tomography, Ice Proxy for the Southern Ocean with 25 carbon atoms, diatom, physical property and geochemical analyses to the core, which contains an annually resolved, continuously laminated archive of phytoplankton bloom events. Bloom events occurred annually to biennially through most of the Holocene, but became less frequent (~2–7 years) at ~4.5 ka when coastal sea ice intensified. We propose that coastal sea-ice intensification subdued annual sea-ice break-out, causing an increased sensitivity of sea-ice dynamics to subdecadal climate modes, leading to a subdecadal frequency of bloom events. Our data suggest that projected loss of coastal sea ice will impact the influence of subdecadal variability on Antarctic margin primary productivity, altering food webs and carbon-cycling processes at seasonal timescales., This research used samples and data provided by IODP expedition 318, sponsored by the US National Science Foundation (NSF) and participating countries under the management of the Consortium for Ocean Leadership, including the Australian and New Zealand International Ocean Discovery Program Consortium. Funding was provided by Royal Society Te Apārangi Marsden Fund (18-VUW-089 to R.M.M. and 15-VUW-131 to N.A.N.B.) and the New Zealand Ministry of Business, Innovation and Employment through the Antarctic Science Platform (ANTA1801). Funding was also provided by the New Zealand Ministry of Business, Innovation and Employment Strategic Science Investment Fund (SSIF) through GNS Science (grant 540GCT32). We acknowledge funding from the Dumont d’Urville NZ-France Science and Technology Programme, MARICE project (Marine and Ice core reconstruction of East Antarctic sea ice variability over the past 2,000 years) (project nos. 45455NF and 19-VUW-047-DDU Catalyst Fund, RSNZ). J.E. and X.C. acknowledge funding by the ERC StG ICEPROXY (203441), the ANR CLIMICE and the FP7 Past4Future (243908) projects. F.J.J.-E. was funded by project 201830I092 (Spanish Research Council). C.E. and F.J.J.-E acknowledge funding by the Spanish Ministry of Science and Innovation (grant CTM2017-89711-C2-1-P), co-funded by the European Union through FEDER funds. C.R.R. was funded by a University of Otago research grant and a L’Oréal-UNESCO For Women in Science Australia and New Zealand Fellowship. The Natural Environment Research Council funded K.E.A. (CENTA PhD; NE/L002493/1) and J.B. (standard grant Ne/I00646X/1). Y.Y. was funded by the Japan Society for Promotion of Science (JSPS) grant no. JP20H00193. S.F.P. was supported by National Science Foundation grant OPP-0732796. R.B.D. was supported by National Science Foundation grants PLR-1644118 and OCE-1129101. The authors acknowledge the Norwegian Polar Institute’s Quantarctica package, and the use of imagery from the NASA Worldview application (https://worldview.earthdata.nasa.gov/), part of the NASA Earth Observing System Data and Information System.

This study was supported by the action "Proyectos I + D + i del Programa Operativo FEDER 2018-Junta de Andalucia-UGR"& nbsp;[grant number B-RNM-144-UGR] , the Spanish Government (Ministerio de Economia y Competividad) and the European Regional Development Fund (ERDF-FEDER) [grant numbers CGL2013-47038-R and CGL2017- 85415-R] , and the Junta de Andalusia [grant numbers P18-RT-871 and Retos P20_00059, and research group RNM-190] . A.G.-A. was supported by a Ramon y Cajal Fellowship RYC of the Spanish Government (Ministerio de Economia y Competividad) [grant number 2015-18966] . A.L.-A PhD was funded by a fellowship of the Spanish Government (Ministerio de Economia y Competividad) [grant number BES-2018-084293] . F.G was financially supported by a Ramon y Cajal Fellowship (RYC2020-029811-I) of the Spanish Government (Ministerio de Economia y Competividad) . The Open Access Publication Charge was funded by the University of Granada/CBUA., Evaporitic lakes such as playa-lakes are characteristic of many arid regions and are unique environments with respect to fauna and flora, while being very vulnerable to climate and environmental fluctuations and threatened by the current global change scenario. Water balance oscillations in these systems can trigger the precipitation or dissolution of different evaporitic minerals, negatively impacting local biodiversity and economic activities. Here, we study the sedimentary record of a small saline pond from a playa-lake complex in southwestern Iberia in order to reconstruct the paleohydrological evolution of this area and assess potential anthropogenic disturbances. The different proxies studied in the ~11.9 ky old sedimentary record of the Laguna de la Ballestera suggest that the greatest lake extension and the highest water levels occurred during the Early Holocene, pointing to the wettest period of the record. Climate transitioned towards more arid conditions during the Middle Holocene, and even more dramatically during the Late Holocene. In this last stage the wetland surface and the water level largely diminished and gypsum precipitation gradually increased pointing towards a negative precipitation/ evapotranspiration balance and lowest water levels. Summer desiccation likely occurred under this scenario, especially after ~1.0–0.9 cal ky BP coeval with the Medieval Climate Anomaly, when gypsum content started to rise abruptly. However, this significant gypsum precipitation was only associated with a massive drop in the siliciclastic content and scarce carbonates (dolomite and calcite) during the last ~400 years. This evidence suggests a shift from a (semi) permanent to a temporal/seasonal hydrological regime. The environmental evolution of this wetland responded to the general climatic evolution of the western Mediterranean during the Holocene, being mostly controlled by changes in insolation. Our data also show that the environmental response of the studied wetland to natural climate variations was only significantly disturbed by human activities since the 20th century, especially in the second half of the century, deduced by abrupt fluctuations in the siliciclastic, gypsum and organic content in the sediments, as well as by the enhanced sedimentary accumulation rates, probably as a response to changes in the hydroperiod of the lake and in the catchment land use., Spanish Government B-RNM-144-UGR, Proyectos I + D + i del Programa Operativo FEDER 2018-Junta de Andalucia-UGR B-RNM-144-UGR, Spanish Government RNM-190, European Commission B-RNM-144-UGR BES-2018-084293, Junta de Andalusia CGL2013-47038-R CGL2017- 85415-R P18-RT-871, Ramon y Cajal Fellowship RYC of the Spanish Government (Ministerio de Economia y Competividad) Retos P20_00059 2015-18966, University of Granada/CBUA RYC 2020-029811-I

In this study, we studied palynomorphs from the alpine record from Laguna Seca in Sierra Nevada, southern Spain to investigate the response of forests and lake environments in the western Mediterranean area to climate changes and to human impact during the latest Pleistocene and Holocene. Xerophyte herbs such as Artemisia, Ephedra, and Amaranthaceae are highest during the late Bölling-Allerod (BA) and Younger Dryas (YD) indicating aridity. Poaceae (grasses) are maximum in the BA and Early Holocene, probably indicating expansion in the barren areas left by glaciers after deglaciation. Forest abundance and composition, in particular of deciduous Quercus and Pinus species indicates maximum humidity during the Early Holocene and aridification in the Middle and Late Holocene. Microcharcoal analysis done on the palynological preparations agrees with the vegetation changes, showing maxima in the Early and Middle Holocene and a decrease in the Late Holocene when the Mediterranean vegetation, and thus fuel availability, diminished. The record of Laguna Seca is particularly interesting with respect to the algae and other aquatic microscopic remains. Pediastrum algae only occurred and showed very high abundances during the end of Heinrich Stadial 1 and beginning of the BA, probably indicating deepest lake conditions with deglaciation. Botryococcus, Debarya, Spirogyra and Zygnema algae also peaked at that climate transition, also supporting lake conditions. Botryococcus increased during the Early Holocene, while the rest of the algae almost vanished, which could indicate that the lake became shallower but very productive until 8200 cal yr BP. From then on, the lake level lowered and became a seasonal lake in the Middle-Late Holocene transition.

The Mediterranean region is a vulnerable area affected, among other environmental threats, by aridification and desertification processes that can cause soil salinization in areas rich in evaporite deposits. This is especially evident in the evaporite lake systems of southern Iberia, where a combination of both natural and anthropogenic causes gives rise to aridification and land degradation. In this study, we performed a multiproxy analysis (magnetic susceptibility, lithology, bulk organic geochemistry, inorganic geochemistry, and mineralogy) in the sedimentary record of the Laguna de la Ballestera playa-lake in southwestern Iberia in order to reconstruct the environmental evolution of this evaporitic area and potential human impacts during the Holocene. The most humid period registered in the Laguna de la Ballestera record was the Early Holocene with significant catchment runoff and high lake water levels. The lake size, lake level and catchment runoff decreased throughout the Middle and Late Holocene. This aridification trend is especially evident in the Late Holocene when gypsum precipitation enhanced. The highest gypsum contents were registered in the last millennium, especially after 1600 cal yr CE, probably related to important changes in the hydrology of the area, shifting from a (semi) permanent to a temporal and seasonal hydrological regime. These trends represent the local environmental responses to the western Mediterranean climate during the Holocene. The studied proxies did not evidence any potential human impact until the last century, when the catchment runoff and the playa-lake hydroperiod changed, probably related to changes in the land use.

We present a high-resolution analysis of seven marine sediment records from the western Mediterranean in a transect from the Algero-Balearic basin to the Alboran Sea, spanning the last 20 ka, to decipher the paleoenvironmental and paleoceanographic evolution of the western Mediterranean Sea. To do so, diverse elemental ratios have been used for reconstructing sediment input variations and paleo-oxygen conditions. In particular, the Ti/Ca ratio has been used to reconstruct variations in the terrigenous and carbonate fractions. However, the specific sedimentary processes controlling this ratio are still poorly understood thus, we also provide new insights for appropriate interpretations in the studied zone. Our results suggest that the Ti/Ca ratio at the suborbital scale is mostly controlled by bottom current intensity, and less influenced by marine productivity, sea level variations and fluvial and eolian inputs. Comparison of diverse records within the western Mediterranean reveals that the Ti/Ca ratio depicted a similar trend in both regions, except during the Heinrich Stadial 1 (HS1) and the Middle Holocene. The HS1 is recorded as a single-phase event in the Algero-Balearic basin, whereas three phases are recognized in the Alboran Sea basin, with a relative minimum in the Ti/Ca ratio. Conversely, during the Middle Holocene, an increase in the Ti/Ca ratio is recorded in the Alboran Sea but not in the Algero-Balearic basin, which could be related to the establishment of the Alboran gyres. Redox sensitive proxies, in particular the Mo/Al, U/Al and Mn/Al ratios, point to different phases within the Organic Rich Layer 1 (ORL1): the ORL1a (15- 11.7 ka cal BP), characterized by more reducing conditions in the Alboran Sea sediments, and the ORL1b 11.7- ~9 ka cal BP) characterized by suboxic-ferruginous conditions. The sea level transgression, the enhanced fluvial input and the shelf flooding played a key role during the ORL1 onset and demise, ncreasing the sedimentation rate in the basin and preventing the organic matter oxidation. During the last 2 ka cal BP, an unprecedented common response is recognized in all the studied regions, showing an overall increase in the Ti/Ca ratio, which may be related to intensified human activity in the Mediterranean area, promoting a greater terrigenous input., SI

Acknowledgments This study was supported by the project B-RNM-144-UGR18 and ARNM- 336-UGR20 of the action “Proyectos I + D + i del Programa Operativo FEDER 2018 - Junta de Andalucía-UGR”, the projects CGL2013-47038-R and CGL2017-85415-R, of the “Ministerio de Economía y Competitividad of Spain and Fondo Europeo de Desarrollo Regional FEDER”, and the research group RNM-190 (Junta de Andalucía), and the projects P18-RT-871 and Retos P20_00059 of Junta de Andalucia. A.G.-A. was also supported by a Ram´on y Cajal Fellowship RYC-2015-18966 of the Spanish Government (Ministerio de Economía y Competividad). A.L.-A PhD is funded by BES-2018-084293 (Ministerio de Economía y Competividad). We thank the Paleomagnetic Laboratory CCiTUB-Geo3Bcn CSIC for the support on paleomagnetic analysis. LV and EB thank the Geomodels Research Institute (UB). We are very grateful to two anonymous reviewers and to the editor Christian Zeeden., The Padul-15-05 sediment core provides an exceptional perspective of the paleoenvironmental and climate change in the Western Mediterranean region for the last ca. 200 kyr. However, even though a robust chronology mainly relying on radiometric dating is available for the last 50 ka, the chronology for the older sediments is not yet fully resolved. Ages for the bottom part of the core (>21 m) were previously inferred from amino-acid racemization dating and sediment accumulation rates. In this work, we provide a more accurate chronology for the older part (>100 kyr) of the Padul-15-05 sediment core record based on the recognition of past Earth's magnetic excursions. We identify an interval prone of reversed polarity samples close to MIS-5e/5 d transition that we correlate to the Blake geomagnetic excursion (116.5 kyr–112 kyr). In addition, we identify an interval of low inclinations and two reversed samples that we interpret as the Iceland Basin geomagnetic excursion (192.7 kyr–187.7 kyr: wide scenario of VGP, Project B-RNM-144-UGR18 and ARNM- 336-UGR20 of the action “Proyectos I + D + i del Programa Operativo FEDER 2018 - Junta de Andalucía-UGR”, Projects CGL2013-47038-R and CGL2017-85415-R, of the “Ministerio de Economía y Competitividad of Spain and Fondo Europeo de Desarrollo Regional FEDER”, Research group RNM-190 (Junta de Andalucía), Projects P18-RT-871 and Retos P20_00059 of Junta de Andalucia, Ramón y Cajal Fellowship RYC-2015-18966 of the Spanish Government (Ministerio de Economía y Competividad), Funded by BES-2018-084293 (Ministerio de Economía y Competividad)

This project was funded through the Joint Industry Project supported by BP, ENI, ExxonMobil, TOTAL, Wintershall Dea and TGS, within the framework of "The Drifters" Research Group at Royal Holloway University of London (RHUL), in conjunction with the projects CTM 2012-39599-C03, CGL2015-66835-P, CTM2016-75129C3-1-R, CGL2016-80445-R (AEI/FEDER, UE) and B-RNM-072-UGR18. This research used data and samples collected by IODP Expedition 339 aboard the Joides Resolution. Data was acquired at the XRF Core Scanner Lab at MARUM -Center for Marine Environmental Sciences, University of Bremen, Germany. Our thanks to Dr Javier Dorador (RHUL, UK) for the high-resolution core imaging treatment, to Dr David Roque (ICMAN-CSIC, Spain) for his help in the hydrographic panels from Fig. 2, and to Dr Angel Puga-Bernabeu (University of Granada, Spain) for revision that helped to improve the original version of the manuscript before submission. This study significantly benefited from discussions with all who attended the IODP Exp. 339 MOW meeting in Heidelberg (Germany) in January 2019. We would like to thank Associate Editor Dr Adam McArthur and the three reviewers, Dr Rachel Brackenridge, Dr Giancarlo Davoli and Dr Adriano Viana, for their positive and constructive comments that helped us improve the manuscript., Despite numerous efforts to properly differentiate between contourites and other deep‐water deposits in cores and outcrops, reliable diagnostic criteria are still lacking. The co‐occurrence of downslope and along‐slope sedimentary processes makes it particularly difficult to differentiate these relatively homogeneous deposits. The main aim of this paper is to identify differences in deep‐water sediments based on Principal Component Analysis of grain size and geochemistry, sedimentary facies, and reinforced by microfacies and ichnofacies. The sediments studied were obtained from two International Ocean Drilling Program Expedition 339 sites in mounded and sheeted drifts in the Gulf of Cadiz. The statistical approach led to the discernment of hemipelagites, silty contourites, sandy contourites, bottom current reworked sands, fine‐grained turbidites and debrites over a range of depositional and physiographic elements. These elements are linked to contourite drifts, the drift‐channel transition, the contourite channel and distal upper slope. When bottom currents or gravity‐driven flows are not the dominant depositional process, marine productivity and continental input settling forms the main depositional mechanism in deep‐water environments. This is reflected by a high variability of the first principal component in hemipelagic deposits. The stacked principal component variability of these deposits evidences that the contourite drift and the adjacent contourite channel were influenced by the interrelation of hemipelagic, gravitational and bottom current induced depositional processes. This interrelation questions the paradigm that a drift is made up solely of muddy sediments. The interrelation of sedimentary processes is a consequence of the precession‐driven changes in the intensity of the Mediterranean Outflow Water related to Mediterranean climate variability, which are punctuated by millennial‐scale variability. Associated vertical and lateral shifts of the Mediterranean Outflow Water, and therefore of its interface with the East North Atlantic Central Water, controlled sediment input and favoured turbulent sediment transport in the middle slope. During the interglacial precession maxima/insolation minima, a more vigorous upper core of the Mediterranean Outflow Water and the enhanced impact of the East North Atlantic Central Water – Mediterranean Outflow Water interface allowed for the development of the sandier contourite deposits., BP within the "The Drifters" Research Group at Royal Holloway University of London (RHUL), ENI within the "The Drifters" Research Group at Royal Holloway University of London (RHUL), ExxonMobil within the "The Drifters" Research Group at Royal Holloway University of London (RHUL), TOTAL within the "The Drifters" Research Group at Royal Holloway University of London (RHUL), Wintershall Dea within the "The Drifters" Research Group at Royal Holloway University of London (RHUL), TGS within the "The Drifters" Research Group at Royal Holloway University of London (RHUL), AEI/FEDER, UE CTM 2012-39599-C03 CGL2015-66835-P CTM2016-75129C3-1-R CGL2016-80445-R, B-RNM-072-UGR18

We estimate the rate of upward pore fluid flow and chlorinity (Cl−) concentrations at depth through a joint analysis of Cl− concentration and temperature versus depth profiles obtained from gas hydrate related test sites drilled and cored in the Krishna-Godavari Basin off the eastern coast of India. Cl−, measured on conventional core samples, decreases with depth at all sites but some of the Cl−profiles show a prominent convex shape, whereas in situ temperature profiles, obtained by the Advanced Piston Coring Temperature probe, are mostly linear at all sites established during the National Gas Hydrate Program 02 Expedition (NGHP-02). Assuming a one-dimensional, time-dependent model for the advection of pore fluid including the sedimentation effect and depth-dependent diffusivity, we estimate darcy velocity and the Cl− concentrations at depth. The best-fit darcy velocity of 1.2–1.6 × 10−11 m/s was estimated for the sites along the crest of the regional anticlinal structure in the NGHP-02 Area B, which was significantly faster than those on the flanks of the anticline. Because the thermal diffusion coefficient is much larger than the chloride ion diffusion coefficient, estimated darcy velocities are not great enough to generate nonlinear temperature profiles with depth, which is consistent with observed linear thermal profiles.

National Gas Hydrate Program Expedition 02 was conducted in 2015 by D/V Chikyu in the western Bay of Bengal, India. Analyses of interstitial water in sediment from four drilling sites along the eastern and western transect in the Krishna–Godavari Basin show that dissolved chloride (Cl−) concentrations decreased with depth from seawater values (>550 mM) near the sediment surface to 300–400 mM at 350–400 m below seafloor (mbsf), suggesting the upward advection of low-Cl– fluid. Excursions of Cl− concentrations toward low values in gas hydrate zones were attributed to the presence of fresh water released by dissociation of gas hydrate during core recovery. At Sites in the western transect, Cl− concentrations below the gas hydrate reservoir (around 280 mbsf) were ca. 60 mM and ca. 45 mM lower than those from above the reservoir, and δ18O and δD values were 1–2‰ and 0.7–1.3‰ higher than those from above the reservoir, respectively. These results suggest that a fraction of migrating low-Cl– fluid is trapped in the gas hydrate zone, causing decreases of δ18O and δD in the residual water due to isotopic fractionation during gas hydrate formation. From mass-balance calculations, we estimated that 10–20% of the advected fluid is trapped at the gas hydrate zone. At all sites, the δ18O and δD values below the gas hydrate zone, representing relatively unaltered low-Cl– fluid, were 0.5–1‰ higher and ca. 13–15‰ lower than those of seawater, respectively. This trend is consistent with water derived from the dehydration of clay minerals, which generally occurs in deeply buried sediments. The contribution of clay mineral dehydration is relatively large at the western transect compared to that in the eastern transect. Our results imply that fluid advection contributes to the accumulation of gas hydrate in the study area.

A new sediment core from Padul, Padul-15-05, provides a long and continuous sedimentary and paleoenvironmental record of the last ∼200 kyr. Here we present a detailed palynological study from this sedimentary sequence with new vegetation and paleoenvironmental data and a climatic interpretation for the last two climatic cycles from the southern Iberian Peninsula in the western Mediterranean region. Pollen analysis from this core shows orbital-scale vegetation oscillations (mainly forced by precession and eccentricity) pointing into insolation as the principal factor controlling vegetation changes at this latitude. The last two glacial-interglacial cycles (from MIS 6 to the present) as well as stadial and interstadial phases are well represented and characterized by significant oscillations in Mediterranean forest in the area, but several differences with respect to other Mediterranean long pollen records can be recognized. Some of these disparities between regions seem to be more related to different precipitation rates linked to the specific geographical features (e.g. strong topographic relief) than to latitudinal differences between the sites. In addition, a lake level reconstruction based on palynological data was developed and compared with the previous reconstruction from this record, representing local environmental changes in the Padul wetland that seems to be related to precipitation/evapotranspiration balance, and therefore, to changes in regional climate conditions. During glacial/stadial conditions recorded by maxima in xerophytes, the p/e increased due to very low evapotranspiration, resulting in high lake levels, while during warmer interglacial/interstadial phases (except for the MIS 5e), mainly represented in this record by maxima in the Mediterranean forest, water level decreased as a result of high evapotranspiration exceeding precipitation input. The comparison of the new Padul-15-05 pollen record with the two previous palynological studies from Padul shows significant differences mainly due to disagreements in the age control of the sequences. This study shows that an accurate age-depth model becomes essential when interpreting long paleoenvironmental and paleoclimate records., This research is supported by the projects CGL2013-47038-R and CGL-2017-85415-R funded by Ministerio de Economía y Competitividad of the Spanish Government, project P11-RNM-7332 from the Junta de Andalucía and the research group RNM0190 (Junta de Andalucía). Jon Camuera acknowledges the PhD funding (BES-2014-069117) provided by the Ministerio de Economía y Competitividad of the Spanish Government under the project CGL2013-47038-R. María J. Ramos-Román also acknowledges the PhD and post-PhD fellowship (P11-RNM-7332) from the Conserjería de Economía, Innovación, Ciencia y Empleo of the Junta de Andalucía. Antonio García-Alix was supported by a Ramón y Cajal fellowship (RYC-2015-18966) from the Ministerio de Economía y Competitividad of the Spanish Government. Thanks to Javier Jaimez for helping with the coring (CIC-UGR). José Carrión thanks the Ministerio de Economía y Competitividad of the Spanish Government (grant number CGL-BOS-2012-34717 and CGL-BOS 2015-68604) and Fundación Séneca (grant number 19434/PI/14).

金沢大学理工研究域地球社会基盤学系, Detailed reconstruction of Indian summer monsoons is necessary to better understand the late Quaternary climate history of the Bay of Bengal and Indian peninsula. We established a chronostratigraphy for a sediment core from Hole 19B in the western Bay of Bengal, extending to approximately 80kyr BP and examined major and trace element compositions and clay mineral components of the sediments. Higher δ 18 O values, lower TiO 2 contents, and weaker weathering in the sediment source area during marine isotope stages (MIS) 2 and 4 compared to MIS 1, 3, and 5 are explained by increased Indian summer monsoonal precipitation and river discharge around the western Bay of Bengal. Clay mineral and chemical components indicate a felsic sediment source, suggesting the Precambrian gneissic complex of the eastern Indian peninsula as the dominant sediment source at this site since 80kyr. Trace element ratios (Cr/Th, Th/Sc, Th/Co, La/Cr, and Eu/Eu*) indicate increased sediment contributions from mafic rocks during MIS 2 and 4. We interpret these results as reflecting the changing influences of the eastern and western branches of the Indian summer monsoon and a greater decrease in rainfall in the eastern and northeastern parts of the Indian peninsula than in the western part during MIS 2 and 4. © 2018. American Geophysical Union. All Rights Reserved.

Mangroves are key ecosystems which respond to global changes in tropical and subtropical regions worldwide. We describe late Holocene mangroves that established close to the southernmost limit (28°S) for this type of ecosystem in South America. Our findings are based on a C dated core obtained from Babitonga Bay, Santa Catarina State, Brazil (26°12′S, 48°33′W). Analysis of palynology, sedimentary facies, isotopic and elemental data shows that mangrove establishment took place ~500 yrs. B.C.E., following an increase in humidity, and expanded further during the Roman Warm Period and at the end of Dark Age Cold Period. Mangrove and precipitation proxies records appear to be sensitive to rainfall patterns imposed both by the expansion/retraction of the Intertropical Convergence Zone and also the interaction with the South Atlantic Subtropical Anticyclone which affects coastal region due to sea surface temperature variations., The authors thank the Coastal Dynamic Laboratory (LADIC-UFPA) , C-14 Laboratory of the Center for Nuclear Energy in Agriculture (CENA-USP) , University of Joinville (UNIVILLE) and Radiocarbon Laboratory (LAC-UFF) for all infrastructure and support. We also thank three anonymous Reviewers and Prof. H. Falcon-Lang for their constructive comments. The first and third author thanks Brazilian Council for Technology and Science-CNPq for fellowship (process 131813/2016-1 , 165911/2015-8 and 305074/2017-2 ). This study was financed by CNPq ( 445111/2014-3 , 405060/2013- 0 ) and FAPESP ( 2011/00995-7 , 2017/03304-1, and 2020/13715-1 ). This study also was financed in part by the Coordenação de Aperfeiçoamento de Pessoal Nível Superior – Brazil (CAPES) – Finance Code 001 .

Oxygen and hydrogen stable isotopes (δ18O and δD) of lake water are sensitive to long-term changes in environmental conditions, including relative humidity, temperature and the evaporation/outflow ratio of the lake. Lacustrine gypsum (CaSO4·2H2O) forms in equilibrium with its parent fluid, so the isotopic composition of its structurally bonded hydration water (GHW) can reflect the δ18O and δD of lake water at the time of mineral formation, with insignificant effects of temperature and salinity on the water-GHW isotope fractionation factors. Using the stable isotope content of gypsum-rich sediment cores as a paleoclimatic proxy, the environmental conditions prevailing in the lake setting at the time of gypsum crystallization can be investigated.Here we apply this method to reconstruct the δ18O and δD of paleo-water in La Ballestera Playa-lake (Seville, southern Spain) throughout the Holocene, from 11.2 cal kyr BP to the present. Gypsum crystallization took place punctually at 11.2 and 4.4 cal kyr BP, and did continuously from 2.9 cal kyr BP to the present. The δ18O and δD showed the lowest values at ~11.2 cal kyr BP (2.3‰ and -1.1‰, respectively) and were significantly higher at ~4.4 cal kyr BP (8.8‰ and 29.2‰, respectively). Likewise, relatively higher values (8.2‰ and 29.8‰, respectively) were recorded at ~2.9 cal kyr BP. Thereafter, the isotopic ratios increased until the present (11.4‰ and 37.1‰, respectively), suggesting increasing aridity and/or hydrological closeness of the lake. A relative minimum in δ18O and δD occurred at ~2.3 cal kyr BP, during the wetter stage of the Iberian Roman Humid Period, while a relative maximum at ~1.1 cal kyr BP was recorded during the Medieval Warm Period.We use a steady-state Isotope Mass Balance to investigate the paleo-hydrological conditions in the lake setting at different stages of the Holocene. Our results suggest that at ~11.2 cal kyr BP La Ballestera Playa-lake was a flow-through lake closely connected to the aquifer with and evaporation/outflow ratio AcknowledgementThis study was supported by the Junta del Andalucía PY18-871 to FG, the project CGL2017-85415-R of the Ministerio de Economía y Competitividad of Spain and Fondo Europeo de Desarrollo Regional FEDER, the project B-RNM-144-UGR18, Proyectos I+D+i del Programa Operativo FEDER 2018 and the research groups RNM-189 y RNM-190 (Junta de Andalucía). Dr. Antonio García-Alix acknowledges the Ramón y Cajal fellowship, RYC-2015-18966. Fernando Gázquez acknowledges the postdoctoral “HIPATIA” program of University of Almería.

The Last Glacial Termination is marked by changing environmental conditions affected by abrupt and rapid climate oscillations, such as Heinrich Stadial 1 (HS1), which is characterized by extremely low sea surface temperatures (SST) and significant changes in northern hemisphere terrestrial landscape (e.g., vegetation) and human dispersion. Previous studies show that overall cold/dry conditions occurred during HS1, but the lack of high-resolution records precludes whether climate was stable or instead characterized by instability. A high-resolution paleoclimatic record from the Padul wetland (southern Iberian Peninsula), supported by a high-resolution chronology and contrasted with other records from southern Europe and the Mediterranean region, shows 1) that the age boundaries of HS1 in this area occurred at ∼18.0 kyr BP (median age = 17,970 cal yr BP; mean age = 18,030 ± 330 cal yr BP) and ∼15.2 kyr BP (median age = 15,210 cal yr BP; mean age = 15,200 ± 420 cal yr BP) and 2) that climate during HS1 was non-stationary and centennial-scale variability in moisture is superimposed on this overall cold climatic period. In this study, we improve the pollen sampling resolution with respect to previous studies on the same Padul-15-05 sedimentary core and suggest a novel subdivision of HS1 in 7 sub-phases, including: i) 3 sub-phases (a.1-a.3) during an arid early phase (HS1a; ∼18.4–17.2 kyr BP), ii) a relatively humid middle phase (HS1b; ∼17.2–16.9 kyr BP), and iii) 3 sub-phases (c.1-c.3) during an arid late phase (HS1c; ∼16.9–15.7 kyr BP). This climatic subdivision is regionally supported by SST oscillations from the Mediterranean Sea, suggesting a strong land-sea coupling. A cyclostratigraphic analysis of pollen data between 20 and 11 kyr BP indicates that the climate variability and the proposed subdivisions characterized by ∼2000 and ∼800-yr periodicities could be related to solar forcing controlling climate in this area., This research is supported by the projects CGL 2013-47038-R and CGL-2017-85415-R, B-RNM-144-UGR18, PhD funding BES-2014-069117 (J.C.) and Ramón y Cajal fellowship RYC-2015-18966 (A.G.-A.) provided by the Ministerio de Economía y Competitividad of the Spanish Government. Additional funding was provided by the project number 316702 from the Academy of Finland for a postdoctoral research contract (J.C.) and the research group RNM0190 and the project P11-RNM-7332 with a postdoctoral fellowship (M.J.R.-R.) from the Junta de Andalucía. M.J.R.-R. acknowledges the postdoctoral funding provided by the European Commission /H2020 (ERC-2017-ADG, project number 788616 ). Finally, we acknowledge two anonymous reviewers and the editor (Donatella Magri) for their very useful corrections and suggestions.

This study was supported by the project B-RNM-144-UGR18 of the action "Proyectos I+D+i del Programa Operativo FEDER 2018 -Junta de Andalucia-UGR", the projects CGL2013-47038-R and CGL201785415-R, of the "Ministerio de Economia y Competitividad of Spain and Fondo Europeo de Desarrollo Regional FEDER", and the research group RNM-190 (Junta de Andalucia). A.G.-A. was also supported by a Marie Curie Intra-European Fellowship of the 7th Framework Programme for Research, Technological Development and Demonstration of the European Commission (NAOSIPUK. Grant Number: PIEF-GA-2012-623027) and by a Ram ' on y Cajal Fellowship RYC-2015-18966 of the Spanish Government (Ministerio de Economia y Competividad). J.C. acknowledges the postdoctoral funding provided by the Academy of Finland (project number 316702). J.L.T. hosted the NAOSIPUK project (PIEFGA-2012-623027) at the University of Glasgow. A.L.-A PhD is funded by BES-2018-084293 (Ministerio de Economia y Competividad). M.J.R.R. acknowledges the postdoctoral funding by the European Research Council (ERC-2017-ADG-788616). This study was supported by an ERC Consolidator Grant (STEEPclim) to D.S. (Grant Agreement No. 647035). E.S. is supported by the DFG Cluster of Excellence 2077 >The Ocean Floor -Earth's Uncharted Interface < at MARUM. We thank Ralph Kreutz for analytical support., The transitional regions between the low and high latitudes of the Northern Hemisphere are highly vulnerable to future climate change yet most of the current climate models usually diverge in their projections. To better understand the dynamics in these regions, the reconstruction of past hydrological fluctuations and precipitation patterns is of paramount importance to accurately constrain present and future climate scenarios. In this study, we investigated paleohydrological dynamics in the western Mediterranean region, a transitional zone between low-mid latitudes and Atlantic - Mediterranean realms. We reconstruct precipitation and moisture source changes during the last -35 ka in order to propose the potential mechanisms driving these oscillations. To do so, we use hydrogen isotopes from sedimentary leaf waxes, more specifically the C31 n-alkane homologue, and a precipitation proxy based on previously published pollen data from a sedimentary core (Padul-15-05) in southern Iberia (Padul wetland -37-N). With this combination we disentangle the coupled effect of precipitation amount and source on the hydrogen isotopic signature of the studied C31 n-alkane record. Our results show three main periods characterized by different precipitation patterns. Low precipitation, mainly linked to a significant contribution from an isotopically-enriched Mediterranean precipitation source, occurred from -30 to -15.5 ka BP and during the last -5 ka, whereas enhanced precipitation with a predominant isotopically-depleted Atlantic precipitation source prevailed from -15.5 to -5 ka BP. This latter stage is here defined as the Western Mediterranean Humid Period (WMHP). In addition, some occasional millennial-scale opposite precipitation patterns can be observed during these climatically distinct periods. These changes in the source of precipitation were likely coupled to a shift in the main rainy season from winter, when Atlantic precipitation prevailed, to late winter-early spring, when the contribution of Mediterranean moisture is higher. Comparison between the studied mid-latitude terrestrial Padul-15-05 core and a low-latitude marine record offshore of northwestern Africa shows clear long-term synchronous responses of both western Mediterranean precipitation and western African monsoon systems to northern Hemisphere atmospheric dynamics, ultimately controlled by orbital forcing and ice-sheets fluctuations., action "Proyectos I+D+i del Programa Operativo FEDER 2018 -Junta de Andalucia-UGR" B-RNM-144-UGR18, Ministerio de Economia y Competitividad of Spain CGL2013-47038-R CGL201785415-R, Junta de Andalucia RNM-190, Marie Curie Intra-European Fellowship of the 7th Framework Programme for Research, Technological Development and Demonstration of the European Commission (NAOSIPUK) PIEF-GA-2012-623027, Spanish Government (Ministerio de Economia y Competividad) RYC-2015-18966, Academy of Finland, European Commission 316702, NAOSIPUK project at the University of Glasgow PIEFGA-2012-623027, Ministerio de Economia y Competividad BES-2018-084293, European Research Council (ERC), European Commission ERC-2017-ADG-788616, ERC Consolidator Grant (STEEPclim) 647035, DFG Cluster of Excellence 2077 >The Ocean Floor -Earth's Uncharted Interface < at MARUM, European Commission

Late Miocene sedimentary records in the Gibraltar arch region hold fundamental information on the Atlantic-Mediterranean connectivity before, during and after the Messinian Salinity Crisis (MSC; 5.96-5.33 Ma). In this work we tackle this still unresolved problem through a detailed foraminifer-based biostratigraphy, micropaleontological and geochemical analyses of four available records (ODP 976B and DSDP 121) and boreholes (Andalucia-G1 and Alboran A1) in the West Alboran Basin (WAB). The combined use of these different analytical techniques together with new seismic stratigraphy enabled us to create a new and revised Upper Tortonian-Lower Pliocene Alboran Sea chronostratigraphic framework and estimate the magnitude of the Zanclean erosion. At Site 976, the dominance of a peculiar cold planktonic foraminifer fauna in the late Tortonian-early Messinian could possibly imply the existence of a proto-Gibraltar Strait, while at ~7.2 Ma, changes towards warmer foraminifer assemblages, increasingly stratified water column and sharp increase in terrestrial input indicate the beginning of the restriction of the Mediterranean from the Atlantic Ocean. Cyclical changes visible both in the elemental composition and foraminifer assemblages from here onward highlight a strong precessional cyclicity, which can be correlated to the first signs of reduced ventilation and sapropel deposition in the Eastern Mediterranean. The integration of seismic profiles and core analyses finally revealed that the Messinian expression in the Alboran basin is limited to two units: one hemipelagic and one chaotic, most probably connected to the MSC final stages. The Messinian succession in the Alboran basin is topped by an unconformity, most likely related with the Zanclean reflooding, which eroded a sedimentary succession of ~1.67 Ma. An extremely rare phosphate (canaphite) and Mg rich minerals were recognized described and associated to interstitial fluids and diagenetic processes.

During the Holocene, 180 m of diatom ooze sediments were deposited in the Antarctic Wilkes Land margin continental shelf at site U1357A (Integrated Ocean Drilling Program Expedition 318, Escutia et al., 2011). Holocene sediments are dominated by rhythmic laminated deposits above a poorly sorted gravelly siltstone diamicton from the Last Glacial Maximum (LGM). CT-scans reveal three events of gravel/sand/silt sediments interbedded within the laminated sediments and interpreted as ice rafted debris (IRD). Two of these events (from 185,1 to 185,45 and 174, 8 to 175,37 meters below seafloor, mbsf) are characterized by dispersed large clasts (1-5cm) within a muddy matrix at the base, transitioning to the top to millimetre-size clasts that are either aligned with the dark and light laminae or dispersed. A third event (176,2 to 177,2 mbsf) is characterized by a structureless sediment sequence with high concentrations of dispersed clasts that are up to 1-2 cm size. We used ImageJ/Fiji software, to conduct a quantitative analysis of grains bigger than 1mm in CT Scan 3D images. Measured parameters include grain size (Feret length), grain orientation (Feret angle), circularity and roundness, among other. In addition, grey scale profiles have been created from the sediment CT-scan images as a density proxy. Quantitative data and density profiles have been used to aid the sedimentological characterization of the Holocene deglaciation section and to infer depositional environment and patterns of deglaciation.Escutia, C., Brinkhuis, H., Klaus, A., and the Expedition 318 Scientists, Proc. IODP, 318: Site 1357. Tokyo (Integrated Ocean Drilling Program Management International, Inc.). doi:10.2204/​iodp.proc.318.105.2011

Palaeoceanographic evidence suggests that glacial periods of the Mid to Late Pleistocene were characterized by markedly different global ocean circulation patterns to modern; in the Atlantic basin, deep waters of Southern Ocean origin increased in volume while above them the core of the North Atlantic Deep Water (NADW) shoaled. Whilst proxy records and modelling efforts continue to clarify this picture, an evidence alluding to the origin of this phenomenon remains elusive. Because of this, our understanding of the sequence of events leading to global glacial conditions remains incomplete. Here we present multi-proxy evidence showing that northward shifts in Antarctic iceberg melt in the Indian–Atlantic Southern Ocean (0–50°E) systematically preceded deep-water mass reorganizations by 1-2 thousand years during Pleistocene-era glaciations. With the aid of iceberg-trajectory model experiments, we demonstrate that such a shift in iceberg trajectories during glacial periods can result in a considerable redistribution of freshwater in the Southern Ocean. This, in concert with increased sea-ice cover, may have enabled positive buoyancy anomalies to effectively escape into the ‘upper’ Atlantic overturning circulation limb, providing a teleconnection between surface Southern Ocean conditions and the formation of NADW. Furthermore, we observe a distinct obliquity pacing of Antarctic iceberg melt both preceding and following the Mid-Pleistocene Transition, become obscured during this interval. With new and existing data we investigate the evolution of orbital forcing at the Agulhas Plateau, considering the implications for ‘Southern Escape’ of freshwater as a key feedback in the transition to the ‘100-kyr world’.

This study was supported by the projects CGL2013-47038-R and CGL2017-85415-R funded by Ministerio de Economia y Competitividad of Spain and Fondo Europeo de Desarrollo Regional FEDER; Seneca Project 20788/PI/18; Junta de Andalucia FEDER Project B-RNM-144-UGR18, Proyectos I + D + i del Programa Operativo FEDER 2018 and the research group RNM-190 (Junta de Andalucia). Alejandro Lopez Aviles acknowledges the PhD funding, BES-2018-084293, provide by Ministerio de Economia y Competitividad of the Spanish Government. Antonio Garcia-Alix acknowledges the Ramon y Cajal fellowship, RYC-2015-18966, provided by the Ministerio de Economia y Competitividad of the Spanish Government. R. Scott Anderson acknowledges travel support from Northern Arizona University., Several organic and inorganic geochemical analyses have been carried out in the sedimentary record of the Borreguil de los Lavaderos de la Reina (BdlR-03), an alpine peat bog located on the north face of the Sierra Nevada (southern Iberian Peninsula). This study permitted a high-resolution reconstruction of paleoenvironmental evolution for the last similar to 2700 cal yr BP in the highest mountain range of southern Iberian Peninsula. An overall trend towards a climatic aridification and a reduction of aquatic environments is observed in this record. Insolation and long-term positive North Atlantic Oscillation trends were the most important factors controlling this aridification, forcing regional and local environmental changes. Four phases are differentiated within the paleoenvironmental evolution of BdlR-03: (1) a pre-bog environment from 2700 to 2600 cal yr BP with important siliciclastic sedimentation and low organic content; (2) a bog environment with important presence of terrestrial vascular plant, water availability and maximum humid conditions between similar to 2600 and similar to 1870 cal yr BP, coinciding with the Iberian-Roman Humid Period; (3) a subsequent drier bog environment, between similar to 1870 and similar to 300 cal yr BP during the Dark Ages, the Medieval Climate Anomaly and the first stages of the Little Ice Age, characterized by lower productivity that affected the development of terrestrial vascular plants and aquatic environments; and (4) a wetland environment with an increase of aquatic algae, development of ephemeral pools and unstable climate conditions between similar to 300 cal yr BP and the present, coinciding with the final stages of the Little Ice Age and the Modern Global Warming. This recent environmental pattern, which is opposite to the general aridification trend in the western Mediterranean, is likely explained by the gradual melting of the perennial ice and/or snow packs at higher elevations in the last centuries. Aeolian inputs would have continuously contributed nutrients to these nutrient-impoverished alpine environments. High dust inputs are especially noticed during the last similar to 200 years, which can be explained by human-induced enhanced aridification and the development of the commercial agriculture in some North African regions. In addition, the environmental signal in the last century seems to be significantly affected by human activities., Ministerio de Economia y Competitividad of Spain CGL2013-47038-R CGL2017-85415-R, European Commission, Junta de Andalucia FEDER Project B-RNM-144-UGR18, Ministerio de Economia y Competitividad of the Spanish Government BES-2018-084293, Ramon y Cajal fellowship by the Ministerio de Economia y Competitividad of the Spanish Government RYC-2015-18966, Fundacion Seneca 20788/PI/18, Junta de Andalucia, Proyectos I + D + i del Programa Operativo FEDER 2018

Comprehending the effects of climate variability and disturbance on forested ecosystems is paramount to successfully managing forest environments under future climate scenarios (e.g., global warming, aridification increase). Changes in fossil pollen abundance in sedimentary archives record past vegetation dynamics at regional scales, mainly related to climate changes and, in the last few millennia, to human impact. Pollen records can thus provide long databases with information on how the environment reacted to climate change before the historical record. In this study, we synthesized fossil pollen data from seven sites from the Sierra Nevada in southern Spain to investigate the response of forests in the western Mediterranean area to millennial-scale climate changes and to human impact during the Holocene. In particular, here we focused on Cedrus pollen abundances, which most-likely originated from Northern Africa and were carried to Sierra Nevada by wind. Cedrus pollen has received little attention in the Iberian Peninsula palynological records, for it occurs in low concentrations and has an African source, and thus this article explores the potential to reconstruct its past history and climate. Although Cedrus abundances are generally lower than 1% in the studied pollen samples, a comparison with North African (Moroccan) Cedrus pollen records shows similar trends at long- and short-term time-scales. Therefore, this record could be used as a proxy for changes in this forest species in North Africa. As observed in the Sierra Nevada synthetic record, the increasing trend of Cedrus pollen during the Middle and Late Holocene closely correlates with decreasing summer insolation. This would have produced overall cooler annual temperatures in Northern Africa (Middle Atlas and Rif Mountains) as well as lower summer evaporation, benefiting the growth of this cool-adapted montane tree species while increasing available moisture during the summer, which is critical for this water-demanding species. Millennial-scale variability also characterizes the Sierra Nevada Cedrus synthetic pollen record. Cedrus abundance oscillations co-vary with well-known millennial-scale climatic variability that controlled cedar abundance and altitudinal distribution in montane areas of N Africa., Support for this study comes from projects CGL2013-47038-R and CGL2017-85415-R funded by Ministerio de Economía y Competitividad of Spain and Fondo Europeo de Desarrollo Regional FEDER; Séneca Project 20788/PI/18; Junta de Andalucía FEDER Project B-RNM-144-UGR18, UGR-FEDER B-RNM-144-UGR18 Proyectos I + D + i del Programa Operativo FEDER 2018 and the research group RNM-190 (Junta de Andalucía). M.J.R.R. acknowledges the postdoctoral funding provided by the European Commission/H2020 (ERC-2017-ADG, project number 788616). J.C. acknowledges the postdoctoral funding provided by the Academy of Finland (project number 316702). A.G.-A. acknowledges the Ramón y Cajal fellowship RYC-2015-18966 provided by the Ministerio de Economía y Competitividad of the Spanish Government. This paper greatly benefited from the reviews of two anonymous reviewers and from the editor Giovanni Zanchetta. Thanks to Rachid Cheddadi, William Fletcher and Nathalie Combourieu-Nebout for kindly providing pollen data from the Alboran Sea and N Morocco records.

The westernmost Mediterranean basins is an exceptional and sensitive region for reconstructing past climate and oceanographic conditions. Geochemical signatures from diverse sediment records in the Alboran Sea and the Balearic basin, in particular, Ti/ca and Fe/Ca ratios, as proxies for the relative abundance of siliciclastic vs. carbonate fraction, have been investigated. These have also been compared with other previously studied records from the western Mediterranean and the Gulf of Cadiz to elucidate the mechanisms triggering the relative variations between the carbonate and siliciclastic fraction. The lithogenic fraction represents around 70% of the sediment in the Alboran basin, which mainly derived from riverine discharge and coastal erosion. Resuspension of fine sediment particles from the slope and the sea floor by bottom-water currents is a relevant process in these basin. The studied records are located between 850 m and 2400 m below the sea level, under the influence of the Western Mediterranean Deep Water (WMDW), which is restricted to a water depth below 500-600 m and to the Moroccan margin. This deep current is formed in the Gulf of Lion, when the superficial and intermediate waters sink by a density increase, and flow out the basin through the Gibraltar Strait, contributing to the Mediterranean Outflow Water (MOW) along with the Levantine Intermediate Water (LIW). The WMDW formation is enhanced during cold and arid periods. The comparison with other previously studied records, support important variations of the mechanisms triggering the relative contribution of carbonate and siliciclastic fractions during the last 20,000 yrs. The, Ti/Ca and Fe/Ca ratios increased during cold and arid periods, such as the Heinrich Event 1 (HE1) and the Younger Dryas (YD). These changes are more prominent in the Balearic basin and the eastern Alboran basin than in the western Alboran basin and the Gulf of Cadiz. Thus, we hypothesized that the increase in the Ti/Ca and Fe/Ca ratios is rather related to the enhanced WMDW production and more remobilization of fine siliciclastic sediments.

EGU General Assembly 2020, Online 4–8 May 2020, [EN] The geometry of large-scale deep ocean circulation is closely linked to processes occurring in the Southern Ocean (SO). The SO is the ‘window’ through which much of the world’s ocean interior interacts with the atmosphere, and understanding the complex relationships coupling SO dynamics to deep circulation can provide valuable insights into biogeochemical and physical processes important to global climate. Of particular interest is how these processes interacted with, and behaved under different climate states, such as the glacial-interglacial cycles of the Pleistocene (0-2.8 Ma), and the intensification of Northern Hemisphere glaciation during the transition from the warm Mid-Pliocene (3.3-3.1 Ma) to the early Pleistocene. Here, we utilise new composite sediment core records (41oS, 25oE, 2700-2900 m water depth) to reconstruct deep chemical and physical ventilation at the Agulhas Plateau, as well as the competing presence of warm Subtropical waters vs cold Subantarctic waters in the surface, over the past ~3 Ma. We present records of the ‘sortable silt’ flow speed proxy, the stable isotope (δ18O, δ13C) composition of benthic foraminifera, bulk sediment element concentrations, and the accumulation of ice-rafted debris (IRD). The sortable silt proxy demonstrates that deep physical ventilation is largely decoupled from deep chemical ventilation as indicated by benthic δ13C, with higher flow speeds coincident with more depleted δ13C. Furthermore, deep ventilation is related to changes in the terrigenous sediment composition: deep flow speeds and δ13C vary concurrently with bulk sediment geochemistry (K/Al, Ti). At the Agulhas Plateau, we interpret deep chemical ventilation and near-bottom flow speeds to reflect changes in the advection of northern-sourced deep waters (e.g. North Atlantic Deep Water and its glacial equivalent) and meridional variability in the location of the deep-reaching Antarctic Circumpolar Current (ACC) and its associated fronts. The presence of IRD at the Agulhas Plateau is controlled primarily by the equatorward survivability far-travelling Antarctic icebergs, and therefore represents the relative presence of cold, iceberg-bearing Subantarctic Zone (SAZ) surface waters. Generally, at times of high near-bottom flow speed and more ‘southern’ terrigenous sediment composition, IRD is higher, implying a meridional expansion of the SAZ. Together, these proxy records provide a continuous and long-term insight into the evolution of coupled surface-deep conditions at the Agulhas Plateau. We postulate that these conditions may reflect the wider geometry of ocean circulation in the SO, documenting the interactions between the ACC and circum-Antarctic fronts with the upwelling, conversion, and export of deep water masses. Our records represent the first multi-proxy reconstruction of this system across climate transitions of the past ~3 Ma, allowing us to explore its evolution across a range of timescales, from million-year to orbital-scale. Furthermore, by measuring multiple proxies on the same samples, we are able to determine the relative phasing between different processes independent of chronostratigraphic uncertainties, for example the timing of SAZ changes vs perturbations in deep ocean circulation at the site.

Alpine ecosystems of the southern Iberian Peninsula are among the most vulnerable and the first to respond to modern climate change in southwestern Europe. While major environmental shifts have occurred over the last ∼1500 years in these alpine ecosystems, only changes in the recent centuries have led to abrupt environmental responses, but factors imposing the strongest stress have been unclear until now. To understand these environmental responses, this study, for the first time, has calibrated an algal lipid-derived temperature proxy (based on long-chain alkyl diols) to instrumental historical data extending alpine temperature reconstructions to 1500 years before present. These novel results highlight the enhanced effect of greenhouse gases on alpine temperatures during the last ∼200 years and the long-term modulating role of solar forcing. This study also shows that the warming rate during the 20th century (∼0.18 ∘C per decade) was double that of the last stages of the Little Ice Age (∼0.09 ∘C per decade), even exceeding temperature trends of the high-altitude Alps during the 20th century. As a consequence, temperature exceeded the preindustrial record in the 1950s, and it has been one of the major forcing processes of the recent enhanced change in these alpine ecosystems from southern Iberia since then. Nevertheless, other factors reducing the snow and ice albedo (e.g., atmospheric deposition) may have influenced local glacier loss, since almost steady climate conditions predominated from the middle 19th century to the first decades of the 20th century., This research has been supported by the Seventh Framework Programme (grant no. NAOSIPUK (623027)), the Ministerio de Economía y Competitividad, Secretaría de Estado de Investigación, Desarrollo e Innovación (grant no. CGL2017-85415-R), the Ministerio de Economía y Competitividad, Secretaría de Estado de Investigación, Desarrollo e Innovación (grant no. CGL2013-47038-R), the Ministerio de Economía y Competitividad, Secretaría de Estado de Investigación, Desarrollo e Innovación (grant no. CGL2011-23483), and the Consejería de Economía, Innovación, Ciencia y Empleo, Junta de Andalucía, Agencia de Innovación y Desarrollo de Andalucía (grant no. P11-RNM 7332). This research has also been supported by grant no. 87/2007 of the Organismo Autónomo Parques Nacionales (OAPN)-Ministerio de Medio Ambiente, the research group no. RNM-190 of the Plan Andaluz de Investigación, Desarrollo e Innovación (Junta de Andalucía), and the Ramón y Cajal Fellowship (fellowship no. RYC-2015-18966) of the Ministerio de Economía y Competitividad, Secretaría de Estado de Investigación, Desarrollo e Innovación.

This paper constitutes the first comprehensive review of animal fossils retrieved in Iberian archaeological sites. Out of 633 items from 82 sites, 143 were analyzed and a further 13 assessed and their status clarified by us on 20 sites. Among others, this study is the first one in Iberia to assess the role played by fossil scaphopods and to carry out a systematic description of shark teeth. The relevance of those 156 fossils we assessed through a comparison with all the finds located in the Iberian literature. Failure to report fossils properly did not allow us to warrant such status for 352 items. We believe that the poor record of fossils in Iberian archaeological sites is the result of a combination of methodological and theoretical constraints. For that reason, we contend that the items herein reported probably represent a fraction, however substantial, of the evidence at hand. In light of the contrasted relevance of fossils for addressing cultural issues, some recommendations and a plea for a more systematic and rigorous search of archaeological specimens are made., This paper is a contribution to project HUM-949-PAI by the Junta de Andalucía and ICAREHB. The Junta de Andalucía granted permission to excavate Hedionda-IV. The research at La Pileta and El Pirulejo were supported by MEC (Ministerio de Economía y Competividad) grants US-1264079 (I+D+i FEDER Andalucía), HAR2013-44269-P and HAR2016-77789-P. Research also benefited from MEC grants HAR2014-55722-P and HAR2017-88325-P, and from grant 19438/PI/14 (SÉNECA Program). AGA was supported by a MINECO Ramón y Cajal Fellowship (RYC-2015-18966). Alfredo Prada (ANMRC) granted permission to study the specimens from Las Aguas, Tesoro, El Juyo, Rascaño and Altamira, and Lola Hernando (Museo Arqueológico Nacional) facilitate the study of fossils from El Oficio. We thank Ana Gómez Díaz, Ana Pajuelo and Alfred Sanchís for photographing the specimens from Campo Real, Grave-5/Señorío de Guzmán and Parpalló.

EGU General Assembly 2020, Online, 4–8 May 2020, [EN] In this study, we synthesized pollen data from seven sites from the Sierra Nevada in southern Spain to investigate the response of forests in the western Mediterranean area to centennial- and millennial-scale climate changes and to human impact during the Holocene. In particular, here we focused in Cedrus pollen abundances, which most-likely originated from Northern Africa and were carried to Sierra Nevada by wind. Although Cedrus abundances are generally lower than 1% in the studied pollen samples, a comparison with North African pollen records shows similar trends at long- and short-term time-scales. Therefore, this record could be used as a proxy for changes in this forest species in North Africa. A Middle and Late Holocene Cedrus pollen increasing trend has been observed in the Sierra Nevada synthetic record, which seems to be the result of decreasing summer insolation. This would have produced overall cooler annual temperatures in Northern Africa (Atlas and Rif Mountains), benefiting the growth of this cool-adapted montane tree species, and lower summer evaporation, increasing available moisture during the summer, which is critical for this water-demanding species. Millennial- and centennial-scale variability also characterize the Sierra Nevada Cedrus synthetic record. Cedrus abundance oscillations could have been produced by well-known millennial-scale climatic variability that controlled cedar abundance in montane areas of N Africa.

To investigate past changes in the Mediterranean Overflow Water (MOW) to the Atlantic, we analyzed the strength of the MOW and benthic δC along the last 250 kyr at Integrated Ocean Drilling Program (IODP) Site U1389 in the Gulf of Cadiz, near the Strait of Gibraltar. Both the strength of the MOW and the benthic δC were mainly driven by precession-controlled fluctuations in the Mediterranean hydrologic budget. Reduced/enhanced Nile discharge and lower/higher Mediterranean annual rainfall at precession maxima/minima resulted in higher/lower MOW strengths at Gibraltar and stronger/weaker Mediterranean overturning circulation. At millennial scale, the higher heat and freshwater loss to the atmosphere during Greenland stadials increased buoyancy loss in the eastern Mediterranean. This enhanced the density gradient with Atlantic water, resulting in a higher MOW velocity in the Gulf of Cadiz. Unlike non-Heinrich stadials, a lower-amplitude increase in velocity was seen during Heinrich stadials (HSs), and a significant drop in velocity was recorded in the middle phase. This weak MOW was especially recognized in Termination I and II during HS1 and HS11. These lower velocities at the depth of Site U1389 were triggered by MOW deepening due to the lower densities of Atlantic intermediate water caused by freshwater released from the Laurentide and Eurasian ice sheets. The intrusion of salt and heat at deeper depths in the Atlantic during HSs and its shoaling at the end could have contributed to drive the changes in the Atlantic Meridional Overturning Circulation during Terminations., This work was funded by the Ministry of Economy of Spain Project RTI2018‐099489‐B‐I00, CGL2015‐68459‐P, and Junta de Castilla y León (UIC 102). We appreciate the work of Jose Ignacio Martin Cruz in sample processing and the picking of planktic and benthic foraminifers. We are very grateful to IODP for inviting some of us to participate in Expedition 339 Mediterranean Outflow and providing the samples used in this study. Part of this work has been done in colaboration with “The Drifters” Research Group at Royal Holloway University of London (RHUL), and it is related to the projects CTM 2012‐39599‐C03, CGL2016‐80445‐R, and CTM2016‐75129‐C3‐1‐R. Also, we thank María Druet (IGME, Spain) for their help in the base map for Figure 1c. Suggestions and comments from Dr. Antje Voelker and Samuel Toucanne were very helpful and substantially improved the last version of this manuscript.

High-altitude peat bogs and lacustrine records are very sensitive to climate changes and atmospheric dust input. Recent studies have shown a close relationship between regional climate aridity and enhanced eolian input to lake sediments. However, changes in regional-scale dust fluxes due to climate variability at short scales and how alpine environments were impacted by climatic- and human-induced environmental changes are not completely understood.Here we present a multi-proxy (palynological, geochemical and magnetic susceptibility) lake sediment record of climate variability in the Sierra Nevada (southeastern Iberian Peninsula) over the Holocene. Magnetic susceptibility and geochemical proxies obtained from the high mountain lake record of Laguna Hondera evidence humid conditions during the early Holocene, while a trend towards more arid conditions is recognized since ĝ1/4 7000 cal yr BP, with enhanced Saharan eolian dust deposition until the present. This trend towards enhanced arid conditions was modulated by millennial-scale climate variability. Relative humid conditions occurred during the Iberian Roman Humid Period (2600-1450 cal yr BP) and predominantly arid conditions occurred during the Dark Ages and the Medieval Climate Anomaly (1450-650 cal yr BP). The Little Ice Age (650-150 cal yr BP) is characterized in the Laguna Hondera record by an increase in runoff and a minimum in eolian input. In addition, we further suggest that human impact in the area is noticed through the record of Olea cultivation, Pinus reforestation and Pb pollution during the Industrial Period (150 cal yr BP-present). Furthermore, we estimated that the correlation between Zr and Ca concentrations stands for Saharan dust input to the Sierra Nevada lake records. These assumptions support that present-day biochemical observations, pointing to eolian input as the main inorganic nutrient source for oligotrophic mountain lakes, are comparable to the past record of eolian supply to these high-altitude lakes., This study was supported by the project P11-RNM 7332 of the “Junta de Andalucía”, the projects CGL2013-47038-R and CGL2015-66830-R of the “Ministerio de Economía y Competitividad of Spain and Fondo Europeo de Desarrollo Regional FEDER”, and the research groups RNM0190 and RNM179 (Junta de Andalucía). We also thank Unidad de Excelencia (UCE-PP2016-05). Jose Manuel Mesa-Fernández acknowledges the PhD funding provided by Ministerio de Economía y Competitividad (CGL2015-66830-R). Antonio García-Alix was also supported by a Marie Curie Intra-European Fellowship of the Seventh Framework Programme for Research, Technological Development and Demonstration of the European Commission (NAOSIPUK; grant number: PIEF-GA-2012-623027) and by a Ramón y Cajal Fellowship RYC-2015-18966 of the Spanish Government (Ministerio de Economía y Competividad) and Marta Rodrigo-Gámiz from the Andalucía Talent Hub Program co-funded by the European Union's Seventh Framework Program (COFUND; grant agreement no. 291780) and the Junta de Andalucía. We thank Santiago Fernández, Maria Dolores Hernandez and Antonio Mudarra for their help recovering the core and Inés Morales for the initial core description and MS data. We thank Jaime Frigola (Universitat de Barcelona) for his help with XRF core scanning.

Padul is one of the few wetland sites in southern Europe and the Mediterranean region that exhibits an unusually large temporal span (>100 kyr) and continuous Quaternary sedimentary record. Previous core-based studies from Padul yielded paleoecological datasets (i.e., pollen and organic geochemistry), but with a poor age control that resulted in rather arbitrary climate inferences. Therefore, precise age control and a multidisciplinary approach is necessary to understand long-term regional environmental and climate change and the associated local response of the Padul wetland environment. Here we present a new long sediment record (Padul-15-05) from this wetland in the southern Iberian Peninsula with the aim of improving the age control of the sedimentary sequence and carrying out up-to-date high-resolution multiproxy analyses. In this study the age control is based on 61 AMS radiocarbon dates for the last ca. 50 kyr BP and on the extent of amino acid racemization (AAR) in mollusc shells extending back ∼118 kyr BP. No numerical ages are available for the bottom part of the core but the sediment accumulation rates (SAR) and the cyclostratigraphic analysis of the multiproxy data suggest that the core preserves a continuous record of the last ∼197 kyr (from late MIS 7 to present) with millennial-scale time resolution. Sedimentological (lithology, magnetic susceptibility, XRD, color), geochemical (XRF, TOC, C/N, % carbonate content) and paleontological (pollen, charophytes, gastropods) data show co-varying cyclical paleoenvironmental changes linked to orbital-scale climatic variability. Silicon, magnetic susceptibility (MS) and total organic carbon (TOC) data show periodicities between ∼26.2–19.6 kyr linked to insolation, which is strongly dominated by precession cycles at this latitude. High values of Si and MS data have been related to high siliciclastic/detrital input from Sierra Nevada range during minima in insolation due to enhanced soil weathering/erosion during regional aridity and lower forest cover recorded by the arboreal pollen, which could also be favored by a minor biogenic productivity. In addition, warm climate conditions during maxima in insolation mostly resulted in negative precipitation/evapotranspiration balance and low lake levels, while cold glacial and stadial periods were mainly characterized by positive precipitation/evapotranspiration balance, and therefore, high lake levels. The improved chronology of the Padul sedimentary sequence along with a multiproxy study permitted us to better relate environmental and vegetation changes to climatic events and to demonstrate how both local (i.e., lake level, sedimentation) and regional (i.e., vegetation) environments responded to orbital-scale climate changes.

Unusual mafic rock fragments deposited in Plio-Pleistocene-aged marine sediments were recorded at Integrated Ocean Drilling Program (IODP) Site U1359, in Wilkes Land, East Antarctica. These fragments were identified from sediment layers deposited between c. 3 and 1.2 Ma, indicating a sustained supply during this time interval. Clinopyroxenes in these basalts are Al–Ti diopside–hedenbergite, uncommon in terrestrial magmatic rocks. A single strong peak in the Raman spectra of a phosphate-bearing mineral at 963 cm-1 supports the presence of merrillite. Although not conclusive, petrological traits and oxygen isotopic compositions also suggest that the fragments may be extra-terrestrial fragments affected by shock metamorphism. Nevertheless, it is concluded that the basaltic fragments incorporated in marine sediments at Site U1359 represent ice-rafted material supplied to the continental rise of East Antarctica, probably from the bedrocks near the proximal Ninnis Glacier. Further studies on Plio-Pleistocene sediments near Site U1359 are required to characterize the unusual mafic rocks described.

Understanding ice sheet behaviour in the geological past is essential for evaluating the role of the cryosphere in the climate system and for projecting rates and magnitudes of sea level rise in future warming scenarios1–4. Although both geological data5–7 and ice sheet models3,8 indicate that marine-based sectors of the East Antarctic Ice Sheet were unstable during Pliocene warm intervals, the ice sheet dynamics during late Pleistocene interglacial intervals are highly uncertain3,9,10. Here we provide evidence from marine sedimentological and geochemical records for ice margin retreat or thinning in the vicinity of the Wilkes Subglacial Basin of East Antarctica during warm late Pleistocene interglacial intervals. The most extreme changes in sediment provenance, recording changes in the locus of glacial erosion, occurred during marine isotope stages 5, 9, and 11, when Antarctic air temperatures11 were at least two degrees Celsius warmer than pre-industrial temperatures for 2,500 years or more. Hence, our study indicates a close link between extended Antarctic warmth and ice loss from the Wilkes Subglacial Basin, providing ice-proximal data to support a contribution to sea level from a reduced East Antarctic Ice Sheet during warm interglacial intervals. While the behaviour of other regions of the East Antarctic Ice Sheet remains to be assessed, it appears that modest future warming may be sufficient to cause ice loss from the Wilkes Subglacial Basin. Studies of an Antarctic marine sediment core suggest that the East Antarctic Ice Sheet retreated in the vicinity of the Wilkes Subglacial Basin during extended warm periods of the late Pleistocene, when temperatures were similar to those predicted to occur within this century.

By presenting benthic foraminifera isotope profiles and bulk geochemical composition of core sediments, we offer a mutiproxy reconstruction of the central Okhotsk Sea oceanography between ∼130 to and ∼115 kyr, related to the marine isotopic stage 5e (MIS 5e). Sediments from the site MR0604-PC7A have been compared with paleo- sea surface temperatures and other records. This multiparameter approach allowed to recognize three periods for MIS 5e evolution, characterized by variations in marine productivity and bottom oxygenation. These variations have been ultimately associated with the production of Okhotsk Sea Intermediate Water and the presence or absence of nutrient contribution from the Pacific Deep Water into central Okhotsk Sea. Aeolian input reconstructed by Th/Sc ratio indicates higher values during the MIS 6 and MIS 5d compared with the MIS 5e. Eu∗ values indicate an input of detrital material from Kurile Islands and East-Kamchatka during the late MIS 5e, absent during the early MIS 5e and glacial periods.

Holocene centennial-scale paleoenvironmental variability has been described in a multiproxy analysis (i.e., lithology, geochemistry, macrofossil, and microfossil analyses) of a paleoecological record from the Padul Basin in Sierra Nevada, southern Iberian Peninsula. This sequence covers a relevant time interval hitherto unreported in the studies of the Padul sedimentary sequence. The ∼ 4700-year record has preserved proxies of climate variability, with vegetation, lake levels, and sedimentological change during the Holocene in one of the most unique and southernmost wetlands in Europe. The progressive middle and late Holocene trend toward arid conditions identified by numerous authors in the western Mediterranean region, mostly related to a decrease in summer insolation, is also documented in this record; here it is also superimposed by centennial-scale variability in humidity. In turn, this record shows centennial-scale climate oscillations in temperature that correlate with well-known climatic events during the late Holocene in the western Mediterranean region, synchronous with variability in solar and atmospheric dynamics. The multiproxy Padul record first shows a transition from a relatively humid middle Holocene in the western Mediterranean region to more aridity from ∼ 4700 to ∼ 2800 cal yr BP. A relatively warm and humid period occurred between ∼ 2600 and ∼ 1600 cal yr BP, coinciding with persistent negative North Atlantic Oscillation (NAO) conditions and the historic Iberian–Roman Humid Period. Enhanced arid conditions, co-occurring with overall positive NAO conditions and increasing solar activity, are observed between ∼ 1550 and ∼ 450 cal yr BP (∼ 400 to ∼ 1400 CE) and colder and warmer conditions occurred during the Dark Ages and Medieval Climate Anomaly (MCA), respectively. Slightly wetter conditions took place during the end of the MCA and the first part of the Little Ice Age, which could be related to a change towards negative NAO conditions and minima in solar activity. Time series analysis performed from local (Botryococcus and total organic carbon) and regional (Mediterranean forest) signals helped us determining the relationship between southern Iberian climate evolution, atmospheric and oceanic dynamics, and solar activity. Our multiproxy record shows little evidence of human impact in the area until ∼ 1550 cal yr BP, when evidence of agriculture and livestock grazing occurs. Therefore, climate is the main forcing mechanism controlling environmental change in the area until relatively recently.

S. Fernández, J.S. Carrión, J. Ochando, P. González-Sampériz, M. Munuera, G. Amorós, J.M. Postigo-Mijarra, C. Morales-Molino, P. García-Murillo, G. Jiménez-Moreno, J.A. López-Sáez, F. Jiménez-Espejo, L.M. Cáceres, J. Rodríguez-Vidal, G. Finlayson, S. Finlayson, C. Finlayson Erratum to “New palynological data from the Late Pleistocene glacial refugium of South-West Iberia: The case of Doñana” [Review of Palaeobotany and Palynology (2021) PALBO 104431] Review of Palaeobotany and Palynology, Volume 296, January 2022, Pages 104566, The Doñana area in southern Iberia is one of the most renowned protected areas of Europe, mostly due to the diversity and value of its wetland ecosystems. The large biogeographical significance of this territory and the outstanding availability of sedimentary archives have made this region a hotspot of paleobotanical research in the Iberian Peninsula. Specifically, the organic deposits on El Asperillo Cliff have been studied during the past few decades from the geomorphological and paleobotanical (pollen, macrofossils) points of view. However, large uncertainties remain concerning the chronology of certain sections of the exposed profile and the paleobotanical potential of this site has not been fully exploited yet. In this study, we revisited El Asperillo with the aims of completing the paleobotanical record and refining the chronology of this site. The age of the studied deposits ranges from ca. 22,000 to 30,900 cal. yr BP according to the radiocarbon dates obtained, thus embracing the particularly cold and dry Heinrich Event 2 and the Last Glacial Maximum. Our palynological results allow inferring the presence of a coastal marshland system. Additionally, the new pollen records highlight the relevance and diversity of pines (Pinus nigra-sylvestris type, P. pinaster, P. halepensis-pinea type) in the Late Pleistocene landscape of Doñana, reinforcing the native status of pines. Last but not least, the results stress the persistence of a highly diverse woody flora in Doñana during the harshest periods of the last glacial cycle, highlighting the importance of this enclave in postglacial vegetation recolonization of the Iberian Peninsula., The development of this work was supported by Projects FEDER/Ministry of Science and Innovation, Agencia Estatal de Investigación CGL-BOS2015-68604-P and PID2019-1049449GB-I00), 261-2011 Organismo Autónomo de Parques Nacionales and Fundación Séneca grant 20788/PI/18

Heinrich Stadial 1 (HS1) is one of the most extreme climate periods of the last glacial cycle, generating extremely low sea surface temperatures (SST) and significant changes in terrestrial landscape (e.g., vegetation). Previous studies show that overall cold/dry conditions occurred during HS1, but the lack of high-resolution records precludes whether climate was stable or instead characterized by instability. A high-resolution paleoclimatic record from Padul (southern Iberian Peninsula), supported by a robust chronology, shows that climate during HS1 was non-stationary and centennial-scale variability in moisture is superimposed on this overall cold climatic period. In this study we improve the resolution and suggest a novel subdivision of HS1 in 7 sub-phases, including: i) 3 sub-phases (a.1–a.3) during an arid early phase (HS1a; ∼18.4–17.2 kyr BP), ii) a humid middle phase (HS1b; ∼17.2–16.7 kyr BP), and iii) 3 sub-phases (c.1–c.3) during an arid late phase (HS1c; ∼16.7–15.6 kyr BP). This climatic subdivision is regionally supported by SST oscillations from the Mediterranean Sea, suggesting a strong land-ocean relationship. A cyclostratigraphic analysis of our pollen data indicates that HS1 climate variability, and thus this subdivision, is characterized by &sim:2000 and ∼800-yr periodicities, suggesting solar forcing controlling climate in this area.

Water masses and depositional environments over the last 500 ka were reconstructed using absolute and relative abundances of lithogenous, biogenous and redox-sensitive elements in four sediment cores from two channel-levee systems of the Wilkes Land continental slope (East Antarctica). Sediments older than the Mid-Bruhnes event (MBE, 430 ka BP) show reduced glacial/interglacial variability in the abundance of elements associated to the terrigenous mineral phases (i.e. Al, Ti, Fe and partly Si). This suggests minor ice-sheet size changes occurred in the Antarctic margin during the pre-MBE “lukewarm” interval. Post-MBE sediments record instead a high variability between glacial and interglacial periods in the concentration of terrigenous and biogenous (i.e. Ca, Ba) elements suggesting larger amplitude changes in both ice-sheet size and ocean conditions toward the gradual establishment of last glacial cycle conditions. Moreover, a marked increase of Mn during the glacial to interglacial transitions, indicates a post-depositional migration of the redox front and re-oxidation of the surface sediment layers linked to major changes in bottom water oxygen conditions associated to Antarctic Bottom Water formation along the margin at the onset of deglaciations., All scientific participants are thanked for shipboard collaboration in the data collection and post-cruise discussions and sample management. U1361 samples were provided by the Integrated Ocean Drilling Programme, Expedition 318. WEGA and MOGAM core samples were provided by the Italian “Programma Nazionale di Ricerche in Antartide”, Antarctic Expeditions 2000 and 2006. MD03-2603 core samples were provided by the Images X-CADO programme. MP acknowledges the EC Human Resources and Mobility Activity - Marie Curie European Re-Integration Grant (ERG) “HoloSed”, Contract 039566. CE and FJJE acknowledge funding from the Ministry of Science and Innovation Grants CTM2017-89711-C2-1-P co-financed by the European Regional Development Fund (FEDER). FJJE acknowledges JAMSTEC-MEXT support. RM was funded by the Royal Society Te Apārangi (NZ) Marsden Fund (18-VUW-089). CT-Scanning was carried out at the Division of Petrophysics of ENI, San Donato Milanese. This paper is a contribution to the SCAR PAIS Programme.

The evaporites of the Realmonte salt mine (Sicily, Italy) are important archives recording the most extreme conditions of the Messinian Salinity Crisis (MSC). However, geochemical approach on these evaporitic sequences is scarce and little is known on the response of the biological community to drastically elevating salinity. In the present work, we investigated the depositional environments and the biological community of the shale¿anhydrite¿halite triplets and the K¿Mg salt layer deposited during the peak of the MSC. Both hopanes and steranes are detected in the shale¿anhydrite¿halite triplets, suggesting the presence of eukaryotes and bacteria throughout their deposition. The K¿Mg salt layer is composed of primary halites, diagenetic leonite, and primary and/or secondary kainite, which are interpreted to have precipitated from density-stratified water column with the halite-precipitating brine at the surface and the brine-precipitating K¿Mg salts at the bottom. The presence of hopanes and a trace amount of steranes implicates that eukaryotes and bacteria were able to survive in the surface halite-precipitating brine even during the most extreme condition of the MSC. Graphical abstract: [Figure not available: see fulltext.]. © 2019, The Author(s)., This work was performed with the support of Japan Society for the Promotion of Science (JSPS) Research Fellowship (16 J07844) to YI and JAMSTEC President Fund to NO.

Alpine ecosystems of the southern Iberian Peninsula are among the most vulnerable and the first to respond to modern climate change in southwestern Europe. While major environmental shifts have occurred over the last ~ 1500 years in these alpine environments, only changes in the recent centuries have led to extreme responses, but factors imposing the strongest stress have been unclear until now. To understand these environmental responses, here, for the first time, we calibrated algal lipids (long-chain diols) to instrumental data extending alpine temperatures backward 1500 years. These novel results highlight the enhanced effect of greenhouse gases on alpine temperatures during the last ~ 200 years and the long-term modulating role of solar forcing. This study also shows that warming rates during the 20th century (~ 0.18 ºC/decade) increased ~ 2.5 times with respect to the last stage of the Little Ice Age (~ 0.07 ºC/decade), even exceeding temperature trends of the high-altitude Alps during the 20th century. As a consequence, temperature exceeded the pre-industrial threshold in the 1950s, being one of the major forcings of the enhanced recent change in the alpine ecosystems from southern Iberia. Nevertheless, other factors reducing the snow and ice albedo (i.e. atmospheric deposition) may have influenced local glacier loss, since steady climate conditions predominated from middle 19th century to the first decades of the 20th century.

The Middle (MP) and Early Upper Paleolithic (EUP) evidences of shellfish collection on the southern Iberian site of Bajondillo cave are presented and compared with Westernmost Mediterranean archaeological sites. The main feature is stasis for Mytilus galloprovincialis represents the dominant taxon during a ∼120kyr temporal sequence. The second feature is the decrease of the shellfishing signal when site distance to the coast increases. The data reveal that shellfish collection was practiced during Marine Isotopic Stage 4, a poorly documented stage in terms of aquatic adaptations. Striking is also that mollusc assemblages evidence an uninterrupted decreasing trend in terms of remains from the earliest to the latest levels, in particular when H. sapiens replaced H. neanderthalensis. Although taxa of secondary importance are too scarce to make reliable inferences, another difference between the MP and EUP collections is the substantial increase of infaunal bivalves in the latter cultural period. Warm and cold water mollusc records match temperature rises and drops although the scarcity of data do not allow one to proceed beyond qualitative statements. Likewise, the prevalence of fresh and brackish water mollusc hint at a permanent presence of freshwater around the site at all times. When compared with assemblages from the Alboran sea region (Westernmost Mediterranean Sea), the Bajondillo cave collections are remarkable for their abundance of mussels. Comparison between Bajondillo cave and Pinnacle Point reveal that infaunal bivalve abundances in the South African site are far higher than those recorded in the MP levels, though not those from the EUP. Whether this feature hints at subtle differences existing between the collection of shellfish by H. sapiens and H. neanderthalensis, reflects a behavioral convergence between the two hominine lineages or represents an inherited cognitive trait from a common ancestor is an issue in need of further analysis., The research of the Bajondillo faunal assemblages was allowed by the Consejería de Cultura of the Junta de Andalucía (Spain) (UPPH/49/06) to one of the authors (MCS). This research has been sponsored by Grants HAR2013-44269-P, HAR2014-55722-P, HAR2016-77789-P and HAR2017-88325-P from the Spanish Ministerio de Economía y Competitividad and 19438/PI/14. The paper constitutes a contribution of Research Group HUM-949 (University of Sevilla, Spain) and the ICArEHB (Universidade do Algarve, Portugal).

The biogeochemistry of hypersaline environments is strongly influenced by changes in biological processes and physicochemical parameters. Although massive evaporation events have occurred repeatedly throughout Earth history, their biogeochemical cycles and global impact remain poorly understood. Here, we provide the first nitrogen isotopic data for nutrients and chloropigments from modern shallow hypersaline environments (solar salterns, Trapani, Italy) and apply the obtained insights to ¿ 15 N signatures of the Messinian salinity crisis (MSC) in the late Miocene. Concentrations and ¿ 15 N of chlorophyll a, bacteriochlorophyll a, nitrate, and ammonium in benthic microbial mats indicate that inhibition of nitrification suppresses denitrification and anammox, resulting in efficient ammonium recycling within the mats and high primary productivity. We also suggest that the release of 15 N-depleted NH 3(gas) with increasing salinity enriches ammonium 15 N in surface brine (¿34.0¿). Such elevated ¿ 15 N is also recorded in geoporphyrins isolated from sediments of the MSC peak (¿20¿), reflecting ammonium supply sufficient for sustaining phototrophic primary production. We propose that efficient nutrient supply combined with frequent bottom-water anoxia and capping of organic-rich sediments by evaporites of the Mediterranean MSC could have contributed to atmospheric CO 2 reduction during the late Miocene. © 2019, The Author(s)., We are grateful to SoSalt Spa and R.N.O Saline di Trapani e Paceco for permission to sample the Trapani solar works. We are also grateful to A. Suzuki of AIST for the measurements of salinity. We thank H. Suga of JAMSTEC for assistance with laboratory work. This study was partly supported by a Japan Society for the Promotion of Science (JSPS) Research Fellowship (16J07844) to YI, Grants-in-Aid (16H02236) and the JAMSTEC President Fund to NO.