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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.

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.

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)

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

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.