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Reconstructing the past variability of marine radiocarbon reservoir effects (MRE) is crucial for generating reliable chronologies for marine species and their consumers. We investigated the temporal MRE variability at the Early-to Mid-Holocene site of El Mazo (Asturias, northern Spain) by using a combination of new and previously published radiocarbon measurements on marine and terrestrial samples. The El Mazo site is characterized by overall well-defined archaeological layers of unknown occupation length with the predominant presence of two mollusc species (Patella vulgata Linnaeus, 1758 and topshell Phorcus lineatus [da Costa, 1778]) which were analysed for radiocarbon measurements. We employed the recently released IntCal20 calibration curve for the northern hemisphere and Bayesian modelling to reconstruct the site's chronology and temporal variability in MREs according to mollusc species. Obtained radiocarbon modelling results, although the estimate precision is not high, reveal a temporal variability in MREs that can be interpreted in view of known past climatic and environmental events such as the 8.2 ka event. The results also revealed differences in MREs according to mollusc species, which need to be taken into account in future chronological modelling. Overall, our results provide reference MRE values for the study of chronologies in northern Iberia during the Early-to Mid-Holocene. In this respect, a non-conservative Delta R reference for local marine samples dating earlier than c. 8.1 ka cal BP is -238 +/- 28 14C years. This research was performed as part of the projects HAR 2016-75605-R and HAR 2017-86262-P, funded by the Spanish Ministry of Economy and Competitiveness, MINECO. During the development of this research AGE was funded by the Basque Country Postdoctoral Programme through a postdoctoral grant (POS_2020_2_0032) and Uni-versity of La Rioja (no code available) . This study has also been sup-ported by the Prehistoric Research Consolidated Group of the Basque Country University (IT-1223-19) , funded by the Basque Country Gov-ernment. PR and RF are funded by the Max Planck Society. We thank the Fishing Activity Service of the Cantabrian Government for the authori-zation to collect modern specimens. We also thank the Max Plank So-ciety, University of La Rioja, Basque Country University (UPV/EHU) , University of Cantabria (UC) and Instituto Internacional de Inves-tigaciones Prehistoricas de Cantabria (IIIPC) for providing support.

Aim To investigate some of the environmental variables underpinning the past and present distribution of an ecosystem engineer near its poleward range edge. Location >500 locations spanning >7,400 km around Ireland. Methods We collated past and present distribution records on a known climate change indicator, the reef‐forming worm Sabellaria alveolata (Linnaeus, 1767) in a biogeographic boundary region over 182 years (1836–2018). This included repeat sampling of 60 locations in the cooler 1950s and again in the warmer 2000s and 2010s. Using species distribution modelling, we identified some of the environmental drivers that likely underpin S. alveolata distribution towards the leading edge of its biogeographical range in Ireland. Results Through plotting 981 records of presence and absence, we revealed a discontinuous distribution with discretely bounded sub‐populations, and edges that coincide with the locations of tidal fronts. Repeat surveys of 60 locations across three time periods showed evidence of population increases, declines, local extirpation and recolonization events within the range, but no evidence of extensions beyond the previously identified distribution limits, despite decades of warming. At a regional scale, populations were relatively stable through time, but local populations in the cold Irish Sea appear highly dynamic and vulnerable to local extirpation risk. Contemporary distribution data (2013–2018) computed with modelled environmental data identified specific niche requirements which can explain the many distribution gaps, namely wave height, tidal amplitude, stratification index, then substrate type. Main conclusions In the face of climate warming, such specific niche requirements can create environmental barriers that may prevent species from extending beyond their leading edges. These boundaries may limit a species’ capacity to redistribute in response to global environmental change.

The adoption of a new funerary ritual with all its social and cognitive meanings is of great importance to understanding social transformations of past societies. The first known occurrence of cremation in the territory corresponding to modern Belgium dates back to the Mesolithic period. From the end of the Neolithic onward, the practice of cremation was characterized by periods in which this rite was predominant and periods of contractions, defined by a decrease in the use of this funerary ritual. This paper aims to quantify such phenomenon for the first time by modeling discontinuities in burial practices through kernel density analysis of 1428 radiocarbon (14C) dates from 311 archaeological sites located in Belgium from the Mesolithic to the Middle Ages. Despite possible taphonomic and sampling biases, the results highlight the existence of periods with a large uptake of cremation rite followed by periods of contractions; such discontinuities took place in correlation with changes in the socio-economical structure of local communities, as, for example, during the later Middle Bronze Age and at the end of the Roman Period., SCOPUS: cp.j, info:eu-repo/semantics/published

Mangrove forests growing at the poleward edges of their geographic distribution are occasionally subject to freezing (&lt, 0 °C) and cold wave (&gt, 0 °C) events. Cold wave effects on mangrove trees are well documented and adaptation to cold stress has been reported for local mangrove populations in the North Atlantic. However, there is less understanding of effects of cold waves on mangroves in the northern Pacific, especially at the regional scale. Moreover, it is unclear if cold tolerant mangrove species of North Asia display variation in resistance to cold temperatures across their geographic distribution. Using a cold wave event that occurred in January 2021, we evaluated the effects of low temperatures on vegetation index (VI) change (relative to a recent five-year baseline) for mangrove forests dominated by Kandelia obovata (Rhizophoraceae) and Avicennia marina (Acanthaceaee) at the northern edge of their geographical range. We used two VIs derived from Sentinel-2 imagery as indicators for canopy health: the normalized difference infrared index (NDII) and the chlorophyll red-edge index (ChlRE), which reflect forest canopy water content and chlorophyll concentration, respectively. We isolated the cold wave effects on the forest canopy from phenology (i.e., cold wave induced deviation from a five-year baseline) and used multiple linear regression to identify significant climatic predictors for the response of mangrove forest canopy VI change to low temperatures. For areas where the cold wave resulted in temperatures &lt, 10 °C, immediate decreases in both VIs were observed, and the VI difference relative to the baseline was generally greater at 30-days after the cold wave than when temperatures initially recovered to baseline values, showing a slight delay in VI response to cold wave-induced canopy damage. Furthermore, the two VIs did not respond consistently suggesting that cold-temperature induced changes in mangrove canopy chlorophyll and water content are affected independently or subject to differing physiological controls. Our results confirm that local baseline (i.e., recent past) climate predicts canopy resistance to cold wave damage across K. obovata stands in the northern Pacific, and in congruence with findings from New World mangroves, they imply geographic variation in mangrove leaf physiological resistance to cold for Northern Pacific mangroves.

The Laurentide Ice Sheet (LIS) was a large, dynamic ice sheet in the early Holocene. The glacial events through Hudson Strait leading to its eventual demise are recorded in the well-dated Labrador shelf core, MD99-2236 from the Cartwright Saddle. We develop a detailed history of the timing of ice-sheet discharge events from the Hudson Strait outlet of the LIS during the Holocene using high-resolution detrital carbonate, ice rafted detritus (IRD), delta O-18, and sediment color data. Eight detrital carbonate peaks (DCPs) associated with IRD peaks and light oxygen isotope events punctuate the MD99-2236 record between 11.5 and 8.0 ka. We use the stratigraphy of the DCPs developed from MD99-2236 to select the appropriate Delta R to calibrate the ages of recorded glacial events in Hudson Bay and Hudson Strait such that they match the DCPs in MD99-2236. We associate the eight DCPs with H0, Gold Cove advance, Noble Inlet advance, initial retreat of the Hudson Strait ice stream (HSIS) from Hudson Strait, opening of the Tyrrell Sea, and drainage of glacial lakes Agassiz and Ojibway. The opening of Foxe Channel and retreat of glacial ice from Foxe Basin are represented by a shoulder in the carbonate data. Delta R of 350 years applied to the radiocarbon ages constraining glacial events H0 through the opening of the Tyrell Sea provided the best match with the MD99-2236 DCPs; Delta R values and ages from the literature are used for the younger events. A very close age match was achieved between the 8.2 ka cold event in the Greenland ice cores, DCP7 (8.15 ka BP), and the drainage of glacial lakes Agassiz and Ojibway. Our stratigraphic comparison between the DCPs in MD99-2236 and the calibrated ages of Hudson Strait/Bay deglacial events shows that the retreat of the HSIS, the opening of the Tyrell Sea, and the catastrophic drainage of glacial lakes Agassiz and Ojibway at 8.2 ka are separate events that have been combined in previous estimates of the timing of the 8.2 ka event from marine records. SW Iceland shelf core MD99-2256 documents freshwater entrainment into the subpolar gyre from the Hudson Strait outlet via the Labrador, North Atlantic, and Irminger currents. The timing of freshwater release from the LIS Hudson Strait outlet in MD99-2236 matches evidence for freshwater forcing and LIS icebergs carrying foreign minerals to the SW Iceland shelf between 11.5 and 8.2 ka. The congruency of these records supports the conclusion of the entrainment of freshwater from the retreat of the LIS through Hudson Strait into the subpolar gyre and provides specific time periods when pulses of LIS freshwater were present to influence climate. (C) 2014 Elsevier Ltd. All rights reserved.

Evidence for the first Neolithic population in central Portugal dates to as early as c. 7600 cal BP. These first farmers were exogenous groups arriving to the Atlantic coast from the Mediterranean Sea. For a few centuries there seems to have occurred an overlap in the region between the Mesolithic Muge huntergatherers and the regional early Neolithic populations. While the trajectory of these first farmers seems to be well established, the fate of the Mesolithic populations is unknown and in generally assumed as resulting in extinction. The recent results from research in the Muge Mesolithic shellmounds (Tagus valley) with the new recovery of various loci with Neolithic occupations including human burials, human DNA, and Strontium analyses seem to indicate evidence of cultural and genetic integration between the Mesolithic and Neolithic populations. This paper will focus on the Mesolithic-Neolithic transition in Portuguese Estremadura and examines the hypothesis that human resilience promoted the cultural and biological integration of the Mesolithic groups into the new exogenous Neolithic communities in central Portugal. (C) 2016 Elsevier Ltd and INQUA. All rights reserved. Fundacao para a Ciencia e Tecnologia (Portugal) [PTDC/HAH/64185/2006, PTDC/HIS-ARQ/112156/2009] info:eu-repo/semantics/publishedVersion

The frequency, duration, and intensity of extreme cold events are widely regarded as primary constraints on the upper latitudinal limits of mangroves. Little data are available on the consequences of recovery (or lack thereof) of non‐floristic components of mangrove ecosystems after a disturbance caused by cold weather. An unusually severe cold wave occurred in southern China in January 2008. The impact of this cold event and the subsequent recovery of mollusks in a Rhizophora stylosa mangrove forest in southern China were evaluated over a 3‐yr study from April 2007 to January 2010. The cold event caused significant mortality of mollusks, which was rapidly followed by an increase in the populations of opportunistic species, and then their subsequent collapse within 6 months. Comparison with data collected in April 2007 (before the cold event) revealed that the density, biomass, and species richness of mollusks decreased by 87.5%, 80.6%, and 56.3%, respectively, except for a transient and compensatory increase in the numbers of benthic mollusks (by 47.5%). Arboreal mollusks were more sensitive to the cold event than benthic species, but both groups showed similar recovery trajectories. After 21 months, the density, biomass, and richness of mollusk species still remained 9.4%, 13.2%, and 26.2% lower than pre‐event. Full recovery took more than 24 months. In comparison to mangrove vegetation, mollusks inhabiting mangroves appeared to be more vulnerable to cold events, but also recovered faster. In conclusion, it took more than 2 yr for the species richness of mollusks to recover from the cold event, and the rate of recovery was slower for the arboreal type.

At Tell Sabi Abyad, Syria, we obtained a robust chronology for the 7th to early 6th millennium BC, the Late Neolithic. The chronology was obtained using a large set of radiocarbon dates, analyzed by Bayesian statistics. Cultural changes observed at ~6200 BC are coeval with the 8.2 ka climate event. The inhabitation remained continuous.

At Tell Sabi Abyad, Syria, we obtained a robust chronology for the 7th to early 6th millennium BC, the Late Neolithic. The chronology was obtained using a large set of radiocarbon dates, analyzed by Bayesian statistics. Cultural changes observed at similar to 6200 BC are coeval with the 8.2 ka climate event. The inhabitation remained continuous.

At Tell Sabi Abyad, Syria, we obtained a robust chronology for the 7th to early 6th millennium BC, the Late Neolithic. The chronology was obtained using a large set of radiocarbon dates, analyzed by Bayesian statistics. Cultural changes observed at similar to 6200 BC are coeval with the 8.2 ka climate event. The inhabitation remained continuous.

Cetacean mass strandings occur regularly worldwide, yet the compounded effects of natural and anthropogenic factors often complicate our understanding of these phenomena. Evidence of past stranding episodes may, thus, be essential to establish the potential influence of climate change. Investigations on bones from the site of Grotta dell’Uzzo in North West Sicily (Italy) show that the rapid climate change around 8,200 years ago coincided with increased strandings in the Mediterranean Sea. Stable isotope analyses on collagen from a large sample of remains recovered at this cave indicate that Mesolithic hunter-gatherers relied little on marine resources. A human and a red fox dating to the 8.2-kyr-BP climatic event, however, acquired at least one third of their protein from cetaceans. Numerous carcasses should have been available annually, for at least a decade, to obtain these proportions of meat. Our findings imply that climate-driven environmental changes, caused by global warming, may represent a serious threat to cetaceans in the near future.

En este trabajo de investigación se amplían los conocimientos sobre las relaciones entre la variabilidad de la precipitación observada en la pradera pampeana y las anomalías en la circulación de la atmósfera detectadas a través del Indice de Oscilación del Sur (SOI) y de las anomalías de la temperatura superficial del mar en el Pacífico ecuatorial. Se analizan los eventos fríos (CE o Niña) y cálidos (WE o Niño) desde comienzos del siglo. Los datos utilizados son las lluvias mensuales de más de 50 localidades de la llanura pampeana con registros desde comienzos de siglo hasta al menos la década del ‘80. Empleando métodos estadísticos de clusters se circunscribe la zona de estudio a tres subregiones de la pampa central de Argentina: Sudoeste, Norte y Este, respectivamente. Los altos valores de los coeficientes de correlación obtenidos entre el Indice de Precipitación Estandarizado (SPI) y el SOI mensual y entre el SPI y la temperatura superficial del mar en la región Niño3 (SST3) están indicando la aptitud de dichos índices para su aplicación en modelos de predicción estadísticos. Las anomalías de la precipitación para los WE y los CE tienen sus correlaciones más fuertes al fin de la primavera y comienzos del verano y son de signos opuestos, con los desfasajes máximos entre Noviembre y Diciembre., In this study the relationship between anomalies in the pampean prairie precipitation and the anomalous behaviour of the atmospheric circulation, particularly focused on the Southern Oscilation Index (SOI) and the sea surface temperature anomalies in the equatorial Pacific is examined. Data consist of secular monthly precipitation for more than 50 selected stations over the pampean plains. Three coherent subregions in the central pampas of Argentina, Southwest, North and East, respectively were determined by clustering methods. Cold and Warm events (CE or La Niña and WE or El Niño, respectively) since the beginning of the century are analyzed with relation to rainfall anomalies. High correlation values were obtained between monthly Standarized Precipitation Index (SPI) and monthly SOI as well as with sea surface temperature in the Niño3 region (SST3), encouriging to perform estatistical modelling for precipitation prediction. Anomalous precipitation for WE and CE have strong correlation values for spring and early summer. Maximum out of phase values between the two cases are reached in November and December., Asociación Argentina de Geofísicos y Geodestas

En este trabajo de investigación se amplian los conocimientos de las relacionesentre los incrementos o deficiencias de las lluvias observadas en la pradera pampeanay las anomalías en la circulación de la atmósfera a través de algunos índiceshemisféricos, en particular, el indice de Oscilación del Sur (SOI) y las anomalías de latemperatura superficial del mar en el Pacífico ecuatorial (SST3). Los datos utilizados son las lluvias mensuales de más de 40 localidades de lallanura pampeana con una longitud de registros desde comienzos de siglo hasta almenos la década del ‘80. Se hace una comparación de indices hídricos que acordes ala finalidades de sus concepciones: agronómica, climática, hidrológica, están mejordetallados en algunos rangos de valores extremos, que en otros. A fin de estudiardichos extremos, sobre todo las sequías, se hace evidente los beneficios del Indice de Precipitación Estandarizada y normalizada, IPE, a escala mensual. Demuestra ser unbuen indicador de sequías y episodios húmedos en la región, no sólo por su escalatemporal variable sino por su mejor definición en rangos de bajos porcentajes defrecuencia. Empleando métodos estadísticos de clusters se circunscribe la zona de estudioa tres subregiones de la pampa central de Argentina: Sudoeste, Norte y Este,respectivamente. Los coeficientes de correlación del IPE para los meses estivales (Nov-Dic-Ene) con el SOI mensual muestran valores significativos al nivel del 5%,desde Junio a Agosto alcanzando un valor de -0.56 entre el SOI de Agosto y el IPE de Diciembre. El signo indica que una alteración en la posición del Anticiclón del Pacífico,que origina SOI negativos/positivos, produciría anomalías positivas/negativas en laprecipitación de los meses de Noviembre y Diciembre cuando esta fasenegativa/positiva del SOI se anticipa a partir del mes de Junio. Las correlaciones entreel IPE mensual y la serie de temperatura superficial del mar en la región Niño3 (SST3).a partir de 1949, son positivas y con valores máximos en las regiones Este y Norte;observándose valores de los coeficientes de hasta 0.58 entre la SST3 de Julio con el IPE de Diciembre y la SST3 de Octubre con el IPE de Noviembre, respectivamente. Enla región Sudoeste sólo alcanza el 0.38 entre la SST3 de Octubre con el IPE de Noviembre. Este resultado sugeriría una mayor influencia del SOI que la SST3 sobrelas lluvias en el sudoeste pampeano. Las anomalías de la precipitación para losepisodios cálidos o fríos definidos por Ropelewski y Halpert (1996) tienen susextremos al fin de la primavera y comienzos del verano. Los desfasajes en elcomportamiento de las dos curvas se producen entre Noviembre y Diciembre, esteúltimo es el mes extremo húmedo. Existe un segundo pico, más débil entre 4 a 7meses más tarde. Se analizan las anomalías del IPE mensual con las cinco fases del SOIestablecidas por Stone y Auliciems (1992). En general, resulta en la región de estudioque la fase 2 y la fase 4 están asociadas a corrimientos negativos en la precipitaciónmediana, deficiencias de lluvia. Por otra parte, las fase 1 y 3 coinciden en relacionarsecon desplazamientos positivos de las medianas de lluvia. Sin embargo, pueden darsesituaciones con perturbaciones dentro de un ciclo positivo o negativo del SOI queverifican lo opuesto. De la inspección de los corrimientos medianos para la primeramitad del período de estudio, 1900-1940, y para la segunda, 1941-1988, se nota entoda la región la influencia positiva del mes de Marzo en fase 4 durante el últimoperíodo pero no se encuentra notorio aumento (como era de esperar por lastendencias positivas de la lluvia en las últimas décadas) en los meses estivales, nien fase 1 ni en fase 3. con respecto al primer período. Se obtuvieron buenosresultados al analizar los corrimientos significativos en las medianas de la precipitaciónde los meses de Noviembre y Diciembre ya que pueden anticiparse a partir de lascondiciones del SOI (fases) desde el mes de Julio. Se considera a Agosto como elmejor mes predictor, con cuatro fases significativas, ya que las fases 1 y 3 del SOIprovocarian anomalías positivas y fases 2 y 4 anomalías negativas para el mes de Diciembre, en la región Sudoeste. In this study the relationship between anomalies in the pampean prairieprecipitation and the anomalous behaviour of the atmospheric circulation, particularlyfocused on the Southern Oscilation Index (SOI) and the sea surface temperatureanomalies in the equatorial Pacific (SST3) is examined. Data consist of secularmonth precipitation for more than 40 selected stations over the pampean plains. Acomparison between different precipitation indexes based on agricultural, climatic andhydrological concepts is performed. In analyzing extreme events, such as drought, the Standarized Precipitation Index (SPI) or IPE in spanish, shows adequacy at a variabletime scale. It has shown good properties when monitoring drought or wet episodes inthe region, particularly, when classifying extreme conditions. Three coherent subregions in the central pampas of Argentina, Southwest, North and East, respectively were determined by clustering methods. The resultsindicate that precipitation over the whole region is significantly influenced by the SOphenomenon. A leading SOI correlated with the summer (Nov-Dec-Jan) anomalousrainfall shows significant coefficients, at 5% significance level, from June to August (peak values of -0.56, for August SOI-December IPE). A negative sign implies ananomalous position of the Pacific High that gives rise to negative SOI starting from June onwards, which in turn would produce positive anomalies in November and December precipitation. A positive SOI phase for the same two months, would berelated to negative rainfall anomalies. Correlations were performed too, betweenmonthly SPI values and the sea surface temperature of the Equatorial Pacific Niño3, SST3. From the latter, possitive and maximun coefficients result for the East and Northregions, with values of 0.58 for each of July SST3 -December IPE and October SST3 November IPE, respectively. The Southwest portion reaches only a coefficient of 0.38for October SST3 - November IPE, suggesting a Stronger SOI impact on the southwestprairies rainfall compare to that of the SST3. Anomalous precipitation for warm andcold events as defined by Ropelewski and Halpert (1996) have extreme values forspring and early summer. Maximum out of phase values between the two cases isreached in November and December, being the latter the extreme wet. A second andweaker peak occurs 4 to 7 months later. In order to clarify this behaviour SPI anomalies are analized through the SOIfive phases established by Stone and Auliciems (1992). Results from the regionevidence that: phases 2 and 4 are related to a negative shift in the median precipitation (rainfall deficit), while phases 1 and 3 are associated with a positive shift in medianprecipitation. Nevertheless, small perturbations during a positive or negative SOI cyclemay produce opposite results. A significatively positive shift during March in phase 4was observed in the period from 1941-1988, when an increase in summer rainfallduring phase 1 and phase 3 had been expected as a consecuence of the high positiveprecipitation trends of the last decades in the region. Significative median rainfall shifts (a=0.05) for November and December areable to be forecasted from SOI conditions starting on July phases. August is the bestpredictor SOI month for December rainfall anomalies in the Southwest region. It showsfour significative phases, 2 and 4 producing negative IPE shifts, and 1 and 3 positiveones. Fil: Scian, Beatriz Viviana. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.