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Ostracod shells are small aquatic crustaceans (0.3 - 5 mm) capable of recording climatic and environmental changes at high-resolution in sedimentary archives of modern and ancient lakes. Their stable low-Mg calcite shell mineralogy makes them ideally suited for targeted geochemical analyses. Therefore, ostracods represent the best candidate to develop a new carbonate clumped isotope (∆47) lacustrine paleothermometer that disentangles and quantifies the effects of global climate changes at regional scale. To establish the relationship between ∆47 and the temperature for ostracod shells, three different species were collected in monitored environments at 4°C and 12°C and one was cultivated in the lab at 23°C. Our results show a linear regression between ostracod-∆47 and calcification temperature that is in agreement with previous published calibrations. This implies that ostracods are an equally-good recorder of (paleo)temperatures as other carbonaceous micro- or macrofossils from the marine realm. Moreover, we report the absence of a consistent offset between the species Eucypris virens and Bradleystrandesia fuscata coming from the same environment and precipitated at the same temperature. This observation suggests the absence of a vital effect at the genus and species level. Samples from shallow Lake Trasimeno (Italy) cover the last 50000 years and confirm the ability of the ostracod clumped-isotope thermometer as well as the absence of vital effect in the fossil record. The new paleothermometer identifies warmer/colder and humid/dryer conditions during Greenland Interstadial and Greenland Stadial/Heinrich events respectively.These findings show that the ostracod-∆47 thermometer has several advantages that makes it an attractive tool for scientific drilling: (i) It is independent of ostracod species and geography. Hence, one can also use endemic species. (ii) It is applicable throughout geological time, as extinct species can be used. (iii) Temperature reconstructions for all environments where ostracods live are within reach. We emphasize that also high-diversity lacustrine environments are suitable for ∆47 analysis, by mixing shells of different species together. This is of particular importance when working with small samples size from sediment cores.The establishment of this new lacustrine proxy enables precise paleoclimatic reconstructions from different climate belts. It opens the door to new high-resolution continental paleoclimate and paleoenvironmental reconstructions and therefore has the potential to be a key tool in future lacustrine drilling in the ICDP framework.

The Eemian (~130 to 115 ka yr BP), also called Marine Isotope Stage (MIS) 5 or the Last Interglacial, was the most recent interglacial period prior to the Holocene. Since temperatures during the Eemian were, on average, ~2 °C warmer than today, studies of this period offer insights into how variables like effective moisture may change under near-future warming scenarios. Such information could improve climate projections for drought-prone regions like the Mediterranean that are particularly vulnerable to future warming. Therefore, a study was initiated to investigate carbonate-rich, Eemian-aged sediments from Padul Wetland (southern Iberia), a site which contains one of the oldest (>200 ka yr) continuous sediment records in the Mediterranean. The resulting proxy record includes stable isotope (δ13C and δ18O) and clumped isotope (Δ47) compositions of aquatic gastropods (e.g., Radix balthica, Anisus spirorbis) and bivalves (e.g., Pisidium sp.). An age-depth model for the entire 200 000-year record was previously established using a mixture of 43 Accelerator Mass Spectrometry (AMS) radiocarbon dates, 10 Amino Acid Racemization (AAR) dates from gastropods (hydrobiid Milesiana schuelei), and two different sediment accumulation rates (SAR) for peat and carbonate/marl lithologies. Variations in δ18O and δ13C closely correspond with the Pollen Climate Index (PCI) for Padul, which is used to discriminate between cold/arid and warm/humid conditions. The close resemblance of these records suggests that variations in δ18O and δ13C at Padul are also sensitive to moisture changes. Variations in δ18O and δ13C of shelly fauna at Padul also resemble shifts in δ18O from the NGRIP ice core(Greenland) and alkenone-based marine sea surface temperature (SST) records of the western Mediterranean region. Similarities among these records underscore the sensitivity of Padul Wetland to regional- and global-scale climatic changes as well as more local moisture variations. One measurement of Δ47 in the aquatic gastropod Radix balthica suggests that average temperatures at Padul during the Eemian were 19.7 ± 2.6 °C, which is consistent with marine records from the Iberian margin. The interpretation of Δ47 in Pisidium sp. is more complicated, perhaps due to vital effects or because Pisidium sp. have highly variable lifespans and individuals that lived only a few months may not reflect average annual conditions. In summary, the stable and clumped isotope records generated in this ongoing study build on previous Eemian-aged reconstructions from southern Iberia by providing higher resolution proxy data constrained by quantitative temperature reconstructions. This research deepens our understanding of how effective moisture in southern Iberia may change in the near future.

Tierra del Fuego in Argentina is a unique location to examine past Holocene wind variability since it intersects the core of the Southern Hemisphere Westerly Winds (SHWW). The SHWW are the most powerful prevailing winds on Earth. Their variation plays a role in regulating atmospheric CO2 levels and rainfall amounts and distribution, both today and in the past. We obtained a piston core (LF06-PC8) from Bahia Grande, a protected sub-basin at the southern margin of Lago Fagnano, the largest lake in Tierra del Fuego. This article focuses on the uppermost 185 cm of this core, corresponding to laminated sediment from the last similar to 6.3 ka. Laminations consist of millimetre-scale paired dark and light layers. Previous studies and new geochemical analysis show that the dark and light layers are characterized by differing concentrations of Mn and Fe. We attribute the distribution of Mn and Fe to episodic hypolimnic oxic-anoxic variations. The age model suggests an approximately bidecadal timescale for the formation of each layer pair. We propose a new model of these redox changes with the SHWW variations. The most likely phenomenon to produce complete water-column mixing is thermobaric instability, which occurs in colder winters with low-intensity SHWW (El Nino-like conditions). In contrast, windier winters are characterized by higher temperatures and reduced mixing in the water column, facilitating a decline in oxygen concentration. Laminations, and the inferred presence of periodic hypolimnion redox changes, are common features of the past similar to 6.3 ka. Geochemical proxy variability is compatible with an intensification of El Nino/Southern Oscillation activity during the past similar to 2 ka., Beatriu de Pinos postdoctoral programme at Agencia de Gestio Academica i Universitaria at Generalitat de Catalunya, National Science Foundation (NSF) ATM-0408668 EAR-1103550, Spanish Government CTM2017-89711-C2-1-P, European Union through FEDER funds, Spanish Government RYC2015-18966

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 North Atlantic Oscillation (NAO) has a major effect on the modern precipitation patterns in the southern Iberian Peninsula and also controlled the hydroclimate of this region in the past [1,2]. The oxygen and hydrogen stable isotopes (δ18O and δD) of lake waters are sensitive to long-term changes in hydrological conditions (e.g. relative humidity, evaporation/outflow ratio, etc.). Here we reconstruct the δ18O and δD values of Laguna Grande de Archidona Lake (Málaga Province, southern Spain) from the stable isotopes of hydration water of gypsum (CaSO4·2H2O) [3] that precipitated and deposited in the lake from 2.7 to 1.4 ka BP.The maximum δ18O and δD of values of the lake water (7.8‰ and 23.9‰, respectively) were recorded at 2.7 ka BP (~700 BCE), suggesting that relatively dry conditions prevailed during the Early Iron Age in southern Iberia. Subsequently, the δ18O and δD of the lake decreased to minimum values (3.0 and -2.2‰, respectively) at 2.4 ka BP, during the early stages of the Iberian Roman Humid Period (~600 BCE to ~400 CE). A relatively arid phase was also recorded at 2.2 ka BP, which preceded a wetter stage at 2.0 ka BP. A longer drier phase occurred later on, from 1.6 ka to 1.4 ka BP, coinciding with the decline of the Western Roman Empire (395-476 CE).The comparison of our paleo-humidity proxy with long-term NAO index [4] shows that the lake water was isotopically enriched during periods of persistent NAO+ mode, suggesting drier and more evaporative conditions and probably lake level lowstands. In contrast, lower δ18O and δD of values of the lake water occurred during periods of NAO- configuration, resulting in wetter and less evaporative conditions and lake level highstands. In summary, our results indicate that the hydrologic balance of Laguna Grande de Archidona during the Iberian Roman Humid Period was controlled by the strength of the long-term NAO and that stable isotopes of gypsum hydration water are a powerful tool for paleo-hydrologic reconstructions. [1] Toney et al. (2020), Quat. Sci. Rev. 106395; [2] Martín-Puertas et al. (2009), Quat. Res. 71, 108–120; [3] Gázquez et al. (2018), Earth Plan. Sci. Lett. 48, 177–188; [4] Faust et al., (2016), Earth Plan. Sci. Lett. 435, 84-93.AcknowledgementThis study was supported by projects PY18-871 and Retos P20_00059 of the Junta de Andalucía, the project CGL2017-85415-R of the Ministerio de Economía y Competitividad of Spain and Fondo Europeo de Desarrollo Regional FEDER and the project B-RNM-144-UGR18. Dr. Antonio García-Alix acknowledges the Ramón y Cajal fellowship, RYC-2015-18966. Dr. Fernando Gázquez acknowledges the Ramón y Cajal fellowship, RYC2020-029811-I.

The continental and marine pollen-based quantitative reconstructions and the West Saharan dust records of the last 150,000 years are excellent paleoclimate proxies to observe variations in humidity and aridity as well as to evaluate similarities and differences in the climate history of the West Mediterranean and West African regions. The quantitative mean annual precipitation reconstruction from the western Mediterranean (southern Iberia and Alboran Sea) shows that during the Last Interglacial and the Early Holocene, the mean annual precipitation in this region was around 600-650 mm/yr, 200 mm/yr higher than the recent values (ca. 450 mm/yr). With respect to the cold Heinrich Stadials (from HS1 to HS6), the West Mediterranean and West Sahara show similar climatic trends and are characterized by strong and synchronous droughts. In particular, during these periods the West Mediterranean stack suggests mean annual precipitation values of 200-350 mm/yr. Here, we aim to elucidate the climate mechanisms affecting both regions during the most arid events of the last glacial period (i.e., Heinrich Stadials) as well as the similarities/differences between the African Humid Periods and the West Mediterranean Humid Periods for the last interglacial-glacial cycle.

This study is was supported by the I + D + i projects CGL2013- 47038-R and CGL2017-85415-R funded by Ministerio Ciencia e Innovación/Agencia Estatal de Investigación/ 10.13039/ 501100011033/ and Fondo Europeo de Desarrollo Regional “Una manera de hacer Europa”, I + D + i projects B-RNM-144-UGR18 and P20_00059 of the action “Proyectos I + D + i del Programa Operativo FEDER - Junta de Andalucía - UGR” and the research group RNM-190. Alejandro López Avilés acknowledges the predoctoral fellowship BES- 2018-084293 provide by the MCIN/ AEI/ 10.13039/501100011033/. Antonio García-Alix acknowledges the Ramón y Cajal fellowship RYC- 2015-18966 provided by the MCIN/ AEI/ 10.13039/501100011033/. Fernando García García collaboration in this study was supported by the I + D + I project CGL2017-89618-R funded by MCIN/ AEI/ 10.13039/ 501100011033/ and FEDER “Una manera de hacer Europa” and the research group RNM-178. José Carrión collaboration in this study was supported by the I + D + I project PID2019-1049449 GB-I00 funded by MCIN/ AEI/ 10.13039/501100011033/ and FEDER “Una manera de hacer Europa” and the fellowship 20788/PI/18 of Fundación Séneca., In an effort to understand how alpine environments from the western Mediterranean region responded to climate variations since the last glacial-interglacial transition, a detailed chronological control and sedimentological analysis, supported by magnetic susceptibility, total organic carbon and C/N data, were carried out on the sedimentary record of Laguna Seca (LS). This is a latitudinal and altitudinally (2259 masl) key alpine wetland site located in the easternmost area of the Sierra Nevada, southern Iberian Peninsula, where sediments accumulated during Heinrich Stadial 1, Bølling-Allerød (B-A) and the Younger Dryas (YD) - previously unrecorded in alpine Sierra Nevada. Climate controlled sedimentation in LS and three coarse-grained and one fine-grained facies association are differentiated, which help us decipher the paleoenvironmental evolution of LS: (1) subaerial cohesionless debris flows during a paraglacial stage; (2) till or nival diamicton during a small glacier/nivation hollow stage; (3) massive mudstone by suspension settling of clays into standing water during a lacustrine stage; and (4) frost-shattering breccia deposited inside the lacustrine stage, probably during the YD, and linked to a periglacial substage. The development of a previously existing small glacial cirque during the Last Glacial Maximum (LGM) in the LS basin at an elevation between 2500 and 2300 m could be supported by the important availability of slope sediments glacially-conditioned such as debris flows, reworked by paraglacial slope processes during the first deglaciation stages, confirming previous studies of landforms in the catchment area and the LGM-Equilibrium Line Altitude estimation above 2400 masl in Sierra Nevada. Mean sediment accumulation rates in the LS sedimentary units (4.21 and 0.28 mm/yr during the paraglacial - small glacier/nivation stage and the lacustrine stage, respectively) confirm that geomorphic activity accelerated just after glaciers retreated due to a slope adjustment and high availability of glacially conditioned sediments. An abrupt change in paleoenvironmental and paleoclimatic conditions occurred in LS at ∼ 15.7 cal kyr BP. This change was probably due to an increase in temperature and precipitation in the western Mediterranean region during the B-A. At LS, this resulted in significant ice-melt, forming a deep-water lake in LS with important organic matter contribution until the end of the Early Holocene (except in the YD when the lake level probably dropped), but elsewhere a general glacier recession in the Sierra Nevada and an expansion of the Mediterranean forest in the southern Iberian Peninsula. Finally, the general long-term aridification that occurred during the Middle Holocene until the present in the western Mediterranean region triggered an important environmental change transforming LS into an ephemeral wetland with an increase in aquatic productivity., I + D + i CGL2013-47038-R, CGL2017-85415-R, Ministerio Ciencia e Innovación, European Regional Development Fund B-RNM-144-UGR18, P20_00059, RNM-190, Junta de Andalucía, Agencia Estatal de Investigación 20788/PI/18, CGL2017-89618-R, PID2019-1049449 GB-I00, RYC-2015-18966, Fundación Séneca

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)

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).

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 .

Due to similarities in morphological features together with strong dispersal abilities, it was thought that some groups of zooplankton (e.g. rotifers, copepods, and cladocerans) have cosmopolitan distributions. In the particular case of cladocerans, recent molecular studies using DNA barcode regions have indicated a different picture, including the existence of multiple regional endemic species and geographical phylogroups; even at very small geographical scales. This has demostrated that cladocera species are less widely distributed than assumed. Morphological identifications of these animals require expertise and high taxonomic specialization. Even so, species identifications are hampered by the small size of the organisms (especially from the littoral zone) and by the sampling cost for obtaining rare species and both parthenogenetic and gamogenetic specimens. The use of molecular techniques can provide new tools to identify cryptic diversity, and by being added to taxonomical approaches, provide more precise data of biodiversity. However, the accuracy of species assignment in metabarcoding relies on the availability of a DNA reference library, which is challenging in areas with high endemicity rates such as the Iberian Peninsula. A preliminary compilation of the available molecular data for the cytochrome (COI) in public repositories (Barcode of Life Data Systems and NCBI GenBank) shows that the available sequences only cover ~60% of the Iberian freshwater cladocerans. The family Daphniidae is very well represented, while the family Chydoridae, which contained most of the Iberian endemism, is underrepresented. We have identified the gaps, and are now focusing on collecting the target organisms to fill the missing taxa of the Iberian library. A compendium of the sampling points, species recovered so far, pitfalls, and future strategy is presented here. The effective completion of a DNA database for cladocerans will have applications not only in biomonitoring programs but to develop DNA-based methods in paleolimnology.

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

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

Desmaninae (water-moles) are common elements in the late Miocene–Pleistocene mammal assemblages from Europe, but knowledge about this group is still scarce. Here we present the desmanines from several early Pliocene localities of the Granada Basin, southern Spain. The species Desmana marci, sp. nov. is described from the sites Calicasas-3 and 4A, characterized, among other traits, by its slightly molarized p4, enormous P2, strongly molarized P3 and P4, and very large metaconule in the M3. Desmana marci shows a typical Desmana i1, with the enamel extending further down anteriorly than posteriorly, but an Archaeodesmana-like I1, low-crowned and bilobed. Desmana marci is proposed as the oldest species of Desmana; its origin lies in Archaeodesmana baetica, and it is in turn interpreted as the ancestor of Desmana verestchagini. Besides, a desmanine of small size and ascribed to Archaeodesmana cf. getica is identified in Calicasas-5A and Purcal-13. This desmanine forms part of a lineage leading to Archaeodesmana elvirae and Archaeodesmana brailloni; this lineage is characterized by an increase in size and in the molarization of the upper premolars. Desmaninae are identified in all the latest Miocene and earliest Pliocene localities from the Granada Basin, evidencing the existence of permanent water bodies. On the contrary, they are not found in sites of similar age in the Guadix Basin, which would have had more arid conditions. The coincident appearance of A. cf. getica in both basins during the early Ruscinian indicates a change towards more humid conditions in the region, allowing the establishment of permanent water flows in the Guadix Basin. http://zoobank.org/urn:lsid:zoobank.org:pub:E3E441D0-CF66-4320-AA2E-17FB7BC10B39., The project CGL2017-82654-P, MINECO/FEDER, UE (Ministerio de Economía, Industria y Competitividad, Spanish Government and EuropeanUnion), the project B-RNM-144-UGR18 of the action‘ProyectosI + D+i del Programa Operativo FEDER 2018–Junta de Andalucía-UGR,’and the research group RNM190 (Junta de Andalucía) supported this work. Furthermore, the Plan Propio deInvestigación (Vicerrectorado de Investigación y Transferencia,Universidad de Granada) funded R.M.-B., and a Ramón yCajal Fellowship (RYC-2015-18966) of the Spanish Government(Ministerio de Economía y Competividad) funded A.G.-A

Alpine regions of the Mediterranean realm are among the most climatically sensitive areas in the world. Thus, alpine wetlands from the southern Iberian Peninsula, in the westernmost part of the Mediterranean region, are highly sensitive sensors of environmental changes. Difficulties have surfaced in separating controls by temperature and/or precipitation in previous paleoenvironmental studies from alpine environments in this area. We present a Holocene biomarker record (n-alkanes and long-chain diols) from a high elevation lake, Laguna de Río Seco (LdRS), in the south of the Iberian Peninsula, which contributes to the identification of these forcing mechanisms. The hydrological history of the area, primarily water availability and evapotranspiration, is reconstructed by means of the n-alkane record, including the indices of average chain length, portion aquatic, and carbon preference index, as well as hydrogen isotopes (δD) of aquatic (δD) and terrestrial (δD) n-alkanes. Temperatures are also estimated using the algae derived long-chain diols. We interpret δD and δD fluctuations as showing changes in the source and amount of precipitation throughout the LdRS record. An Atlantic precipitation source appears to have predominated during the early-middle Holocene, but an occasional Mediterranean influence with an isotopic enrichment in precipitation is detected in the middle-late Holocene that is likely related to the setting of the current atmospheric pattern in southeastern Iberia under the joint control of the North Atlantic Oscillation (NAO) and the Western Mediterranean dynamics, such as the Western Mediterranean Oscillation (WeMO). Our new record from LdRS is consistent with a generalized trend of a humid early-middle Holocene with low temperature variability, evolving towards an arid middle-late Holocene with abrupt temperature changes. In addition to these long-term trends during the last ∼10,500 years, two phases of climate instability, evidenced by abrupt depletions in δD, have been identified at the end of these periods, one between ∼6500 and 5500 cal yr BP and another in the last ∼500 years. These episodes would represent strengthened winter cold conditions that favoured the persistence of snowpack and frozen soil in the catchment, causing reduced terrestrial plant growth and low lake evaporation. According to the long-chain diol record, temperatures during these phases were relatively low, but experienced abrupt increases at the end of each period., This study was supported by the project P11-RNM-7332 of the “Junta de Andalucía”, the projects CGL2013-47038-R and CGL-2017-85415-R of the “Ministerio de Economía y Competitividad of Spain and Fondo Europeo de Desarrollo Regional FEDER” and the research group RNM0190 (Junta de Andalucía). 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 Ramón y Cajal Fellowship RYC-2015-18966 of the Spanish Government (Ministerio de Economía y Competividad). J.L.T. was also supported by a Small Research Grant by the Carnegie Trust for the Universities of Scotland and hosted the NAOSIPUK project (PIEF-GA-2012-623027). We also want to thank the Editor, P. Rioual and two anonymous reviewers for their useful comments that improved the final version of the manuscript.

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.

Remote small alpine lakes and wetlands from the Sierra Nevada mountain range (southern Spain) are exceptional ecological sensors of global change and preserve a complete post-glacial Holocene sedimentary record. Several organic and inorganic geochemical analyses carried out in the sedimentary record of the Borreguil de los Lavaderos de la Reina, a small bog located in the north face of the Sierra Nevada at 2421 m, have allowed us to reconstruct climate, vegetation and human interaction in the highest mountain range in southern Iberia in the last 3000 years. This study shows that during the Late Holocene there is a progressive climatic aridification, which produced a reduction in the aquatic environments in Sierra Nevada. The studied peat bog geomorphology and surrounding areas also conditioned the evolution of the local vegetation. An increasing trend in the detrital eolian input from northern Africa, as well as an important anthropic impact in the ecosystems (artificial drainage system among other activities) are observed in the studied record in the last century.

The study of climate variability in especially sensitive areas is crucial for a better understanding of the response of Earth’s different components to abrupt changes and envisage future climate responses. In this regard, the southern Iberian and western Mediterranean regions have demonstrated hemispheric-scale teleconnections during the last glacial period. Long-records from continental sedimentary archives are scarce, and the Padul wetland represents one of the longest and most continuous continental record in this area, detecting climate variability at centennial to millennial-scale from the Pleistocene to the Holocene. The applicability of organic-based proxies in this organic rich continental archive is a promising tool because the variations in different biomarkers are closely related to biological sources and environmental factors such as temperature. Particularly interesting from a paleoclimatic point of view are glycerol dialkyl glycerol tetraethers (GDGTs), which are membrane lipids from Bacteria and Archaea, ubiquitous in a range of natural archives, including wetlands. Previous works have demonstrated their applicability as a significant past continental air temperature proxy, where the distribution of bacterial branched GDGTs (brGDGTs) is correlated with mean annual air temperature (MAAT) and soil pH. Here we present a first quantification of past temperatures using brGDGTs in the Padul sedimentary record. Preliminary results have evidenced substantial variations in derived-MAAT and distribution of the different brGDGTs during the last 36 kyr that are consistent with abrupt climate periods, such as Henrich Stadial 1 and the Holocene onset. Nevertheless, different absolute MAAT values using the peat-specific calibration and the mineral soil calibration have been obtained and they need to be evaluated.

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.

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.

The gerbillid Myocricetodon is mainly known from the Miocene of Africa and Asia, but some small samples of this genus have been identified in southwestern Europe, interpreted as immigrants driven by the Messinian Salinity Crisis. However, the specific determination of these European populations and their relationships with African forms have proved controversial. The population from Negratin-1 (Guadix Basin, southern Spain) was attributed to the African species Myocricetodon jaegeri, but other European samples have still not been determined at the specific level. Here we describe the material of Myocricetodon from Almenara-M (eastern Spain), which represents the most abundant sample of the genus known from Europe, confirming its assignation to M. jaegeri. We also analyze material from Salobrena, Pino Mojon (southern Spain) and Castelnou-3 (southern France), concluding that these samples belong to the same species. The presence of these coeval and conspecific populations of Myocricetodon is explained by a single migratory event from northern Africa. The occurrence of Myocricetodon, interpreted as an indicator of warm and arid conditions, is restricted to southern and eastern Spain and the southeastermost extreme of France, being mainly limited to the Mediterranean coast. It is absent in other Iberian areas, such as the Granada, Cabriel and Teruel basins, despite their rich and well-studied record of late Miocene mammals. This distribution suggests the existence of different environmental (more humid) conditions in those areas during the latest Miocene, as already proposed for the Granada Basin. Our data also indicate that the presence of Myocricetodon in Europe was limited to a short interval close to the Miocene-Pliocene boundary, contrarily to other gerbils, namely Debruijnimys, which persisted during the Pliocene. This suggests that Myocricetodon could be extremely sensitive to environmental factors and its occurrence in Europe was linked to a specific moment of arid conditions.

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.

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.

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.

Mediterranean mountainous environments are biodiversity hotspots and priority areas in conservation agendas. Although they are fragile and threatened by forecasted global change scenarios, their sensitivity to long-term environmental variability is still understudied. The Sierra Nevada range, located in southern Spain on the north-western European flanks of the Mediterranean basin, is a biodiversity hotspot. Consequently, Sierra Nevada provides an excellent model system to apply a palaeoecological approach to detect vegetation changes, explore the drivers triggering those changes, and how vegetation changes link to the present landscape in such a paradigmatic mountain system. A multi-proxy strategy (magnetic susceptibility, grain size, loss-on-ignition, macroremains, charcoal and palynological analyses) is applied to an 8400-year long lacustrine environmental archive from the Laguna de la Mosca (2889 masl). The long-term ecological data show how the Early Holocene pine forests transitioned towards mixed Pinus-Quercus submediterranean forests as a response to a decrease in seasonality at ~7.3 cal. kyr BP. The mixed Pinus-Quercus submediterranean forests collapsed drastically giving way to open evergreen Quercus formations at ~4.2 cal. kyr BP after a well-known aridity crisis. Under the forecasted northward expansion of the Mediterranean area due to global change-related aridity increase, mountain forests inhabiting territories adjacent to the Mediterranean Region could experience analogous responses to those detected in the Sierra Nevada forests to the Mid to Late Holocene aridification, moving from temperate to submediterranean and then Mediterranean formations.

The effect of recent climatic warming is significant in the Mediterranean region, especially in high-mountain areas. This study uses multiple sedimentary proxies from Río Seco Lake, a remote alpine lake in the Sierra Nevada, southeastern Spain, to reconstruct recent environmental and ecological changes in the lake and catchment. Two main climatic periods can be distinguished during the past 180 years: Period One (1820 to ~ 1920s) characterized by colder and wetter conditions than the more recent Period Two (~ 1920s to the present), characterized by warmer and drier conditions. Independent proxies such as subfossil chironomid assemblages, n-alkane indices, pollen data and/or spectrally inferred chlorophyll-a concentrations indicate a longer ice-cover period, colder water temperature and more pronounced accumulation of snow in the catchment during Period One than in Period Two, likely producing water stress for catchment plant growth because of the low rate of ice melting in Period One. As temperature increases and precipitation decreases from the 1920s onwards, a wider development of wetland plants is observed, which is associated with the longer warm season that contributed to snow and ice melting in the catchment. This continuing temperature rise and precipitation decrease over the past 60-years by ~ 0.24°C per decade and –0.92 mm/y, respectively, lead to an important increase in chlorophyll-a and changes in lake biotic assemblages. Major chironomid community structure changes to warmer water taxa were recorded, resulting in a 2°C increase in mean July air temperature inferred by chironomids from ~ 1950 onwards. An inferred increase in primary production for the past few decades is consistent with higher temperatures, while wider development of wetland plants is associated with longer warm season. The coherence between independent environmental proxies, each associated with distinct mechanistic linkages to climatic shifts, strengthens our interpretations of a recent warming trend and an intensification of summer drought in this high-mountain area leading to distinct changes in the lake and its catchment. The impact of this climate change on the summits of Sierra Nevada and its influence transcends its geographical limits because these systems provide ecosystem services to a vast area., The authors wish to acknowledge all colleagues for help with fieldwork. We thank Paleoecological Environmental Assessment and Research Laboratory (PEARL) of Queen’s University at Kingston for processing the spectrally inferred chlorophyll-a record. This study was funded by MMA Project 87/2007 and MINECO Project CGL 2011-23483 to C. P.-M. and a FPU fellowship (AP2007-00352) to L. J. from the Spanish Ministry of Education and Science. A.G.-A. was also supported by a Marie Curie IEF of the 7th Framework Programme of the European Commission (NAOSIPUK. Grant Number: PIEF-GA-2012-623027) and a Ramón y Cajal fellowship (RYC-2015-18966) from the MINECO.

Westernmost Europe constitutes a key location in determining the timing of the replacement of Neanderthals by anatomically modern humans (AMHs). In this study, the replacement of late Mousterian industries by Aurignacian ones at the site of Bajondillo Cave (Malaga, southern Spain) is reported. On the basis of Bayesian analyses, a total of 26 radiocarbon dates, including 17 new ones, show that replacement at Bajondillo took place in the millennia centring on ~45–43 calibrated thousand years before the present (cal ka bp)—well before the onset of Heinrich event 4 (~40.2–38.3 cal ka bp). These dates indicate that the arrival of AMHs at the southernmost tip of Iberia was essentially synchronous with that recorded in other regions of Europe, and significantly increases the areal expansion reached by early AMHs at that time. In agreement with human dispersal scenarios on other continents, such rapid expansion points to coastal corridors as favoured routes for early AMH. The new radiocarbon dates align Iberian chronologies with AMH dispersal patterns in Eurasia. New 43–45 ka dates for stone tool assemblages associated with anatomically modern humans (AMHs) at the southern Spanish site of Bajondillo suggest an early AMH incursion and weaken the case for late Neanderthal persistence in the region.

43 pages, 31 figures, The Miocene is an essential period in the configuration of the present-day relief of the Betic Cordillera and the South Iberian continental margin, which determined the structure and evolution of the Neogene sedimentary basins (Fig. 3.1). The crustal thinning processes that occurred during the early and middle Miocene, after the main metamorphic events, generated major low-angle normal faults that separate the main metamorphic complexes. Although a wide variety of tectonic models have been proposed for this setting, most of them are related to delamination or to subduction with associated roll-back. During the late Miocene, the relatively flat and low relief of the continental crust facilitated the accumulation of sedimentary deposits, which are interlayered with volcanic rocks in the eastern Betic Cordillera and Alborán Sea. The continuous Eurasian-African convergence finally produced regional uplift since the late Miocene and the development of large late regional E-W to NE-SW folds, which determine the main reliefs

High-reso CE to lution pollen analysis, charcoal, non-pollen palynomorphs and magnetic susceptibility have been analyzed in the sediment record of a peat bog in Sierra Nevada in southern Iberia. The study of these proxies provided the reconstruction of vegetation, climate, fire and human activity of the last ∼4500 cal yr BP. A progressive trend towards aridification during the late Holocene is observed in this record. This trend is interrupted by millennial- and centennial-scale variability of relatively more humid and arid periods. Arid conditions are recorded between ∼4000 and 3100 cal yr BP, being characterized by a decline in arboreal pollen and with a spike in magnetic susceptibility. This is followed by a relatively humid period from ∼3100 to 1600 cal yr BP, coinciding partially with the Iberian-Roman Humid Period, and is indicated by the increase of Pinus and the decrease in xerophytic taxa. The last 1500 cal yr BP are characterized by several centennial-scale climatic oscillations. Generally arid conditions from ∼450 to 1300 CE, depicted by a decrease in Pinus and an increase in Artemisia, comprise the Dark Ages and the Medieval Climate Anomaly. Since ∼ 1300 to 1850 CE pronounced oscillations occur between relatively humid and arid conditions. Four periods depicted by relatively higher Pinus coinciding with the beginning and end of the Little Ice Age are interrupted by three arid events characterized by an increase in Artemisia. These alternating arid and humid shifts could be explained by centennial-scale changes in the North Atlantic Oscillation and solar activity.

Aim: The Messinian salinity crisis (MSC) was an extraordinary geological event that affected the whole Mediterranean region as well as the global marine circulation between 5.97 and c. 5.33 Ma. One of its most direct effects was the emersion of land masses and the subsequent establishment of land bridges that led to common terrestrial faunal exchanges. However, the details of the onset of these exchanges have been a matter of controversy. New findings from southern Iberia of small mammal remains with African similarities have enabled us to review the Messinian faunal exchanges in the Mediterranean region. Location: Mediterranean region. Methods: Small mammal remains with African similarities from two new southern Iberian sites were studied. The small mammal associations of eight Miocene–Pliocene North African sites were also reviewed. Results: Two taxa with African similarities were identified at the Iberian study sites: Debruijnimys almenarensis and a Ruscinomys-like form (cf. Ruscinomys) with a strong spur in the lingual lobe of the anterocone in the M1, a feature observed in North African Ruscinomys and eastern Mediterranean Byzantinia. The taxonomic status of some North African species and/or genera, such as Castillomys, Occitanomys and Prolagus, should be revised according to the new phylogenetic relationships established in European faunas. Main conclusions: Two hypotheses can be proposed for the origin of the African Ruscinomys: (1) among the Iberian Ruscinomys or (2) from the eastern Mediterranean Byzantinia. Our data, currently from only a few, albeit significant, taxa, tend to support an Iberian origin. The discussion presented in this paper suggests an age near the closure of the last Betic Gateway (c. 6.18 Ma) for the first small mammal exchange between Africa and Europe, as well as a single migratory wave of small mammals, filtered by their ecological preferences from this point until the end of the MSC.

The Mediterranean Outflow (MOW) is generated by deep and intermediate waters from different basins in the Mediterranean Sea. Despite the number of studies on Mediterranean water masses, little work has been done on the source and properties of intermediate waters in the westernmost Mediterranean Sea and their links with MOW. Here we examine three marine sediment records spanning the last 20 kyr, located at key depths to trace intermediate waters along the Alboran Sea. We use a combination of redox-sensitive elements, which can serve as proxies to reconstruct variations in the water column oxygenation and the Nd isotopic composition of foraminiferal ferromanganese coatings, in order to reconstruct water mass provenance of Eastern/Western Mediterranean waters. As measured, eNd < − 9.2 and a low U/Th ratio during glacial periods can be attributed to the presence of Western Mediterranean Deep Water (WMDW) at the study sites. During deglaciation, higher Nd isotopic compositions and U/Th ratios point to an enhanced contribution of the modified Levantine Intermediate Water (LIW). The comparison between our data and other LIW and MOW records suggests that i) the lower branch of MOW is linked to WMDW during the glacial period, ii) the middle MOW branch follows LIW activity during deglaciation, while iii) the upper branch is more active during late Holocene, coinciding with LIW formation increase after sapropel deposits. This reconstruction has significant implications for an understanding of the MOW evolution.