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During the 20th century, there has been an ongoing agricultural expansion and global warming, two of the main determinants influencing biodiversity changes in Argentina. The red hocicudo mouse (Oxymycterus rufus) inhabits subtropical grasslands and riparian habitats and has increased its abundance in recent years in central Argentina agroecosystems. This paper describes the long‐term temporal changes in O. rufus abundance in Exaltación de la Cruz department, Buenos Aires province, Argentina, in relation to weather fluctuations and landscape features, as well as analyzes the spatio‐temporal structure of captures of animals. We used generalized liner models, semivariograms, the Mantel test, and autocorrelation functions for the analysis of rodent data obtained from trappings conducted between 1984 and 2014. O. rufus showed an increase in abundance across the years of study, with its distribution depending on landscape features, such as habitat types and the distance to floodplains. Capture rates showed a spatio‐temporal aggregation, suggesting expansion from previously occupied sites. O. rufus was more abundant at lower minimum temperatures in summer, higher precipitation in spring and summer, and lower precipitations in winter. Weather conditions affected O. rufus abundance, but there was local variation that differed from global patterns of climate change. [ABSTRACT FROM AUTHOR]

This paper explores how significant are the ecological and climatic variables to influence the stable isotopes of guanacos. Lama guanicoe bone collagen carbon and nitrogen stable isotope ratios are assumed as a macro regional average value in west Argentina, mostly as a baseline to model archaeological human diet. If stable isotopes on mammals reflex ecology and climate, we need to know how those variables influence mammals bone stable isotope ratio. This paper analyses the 13C/12C and 15 N/14N ratio on bone collagen on 122 guanacos from Northwest Patagonia during the Holocene. The results confirm significant variation in both isotopes between Monte and Andean-Patagonian specimens. Guanacos from Monte shows higher δ13C and δ15N than those from Andean-Patagonian. Temporal trends indicate variation through Holocene but this variation is not spatially homogeneous. In this paper we suggest that Medieval Climatic Anomaly had stronger effect in Monte desert than in Patagonia desert, generating driest and/or hottest conditions between 1250 and 600 years BP. Those variations need to be considered to reconstruct human diet at least during the second part of the Holocene. [ABSTRACT FROM AUTHOR]

In this paper we review the growing evidence of anthropogenic landscapespresent in the semi-deciduous neotropical forest biomes of eastern NW Argentina,which have remained relatively neglected in favour of arid to semi-arid western Andean regions. The evidence gathered in de El Alto-Ancasti provides animportant case study where multidisciplinary methodologies have beenapplied to sites that document the emergence and variability in food productionstrategies across the eastern Andean forests and grasslands of NWArgentina. We discuss evidence offarming structures from archaeological surveys, plant management from phy-tolith analysis, and the tempo and nature of settlement from archaeological excavations undertaken at a variety of sites in the El Alto Ancasti mountainrange. We suggest that the communities that inhabited this region during thefirst millennium AD (ca. 1500–1000 BP) established a strategy of 'overlappingpatchworks' of food production that were able to contend with considerableseasonal variability. We argue that, through the use of cross-channelling, low river areas, erosion control techniques and the establishment of mesothermal crops,including maize, legumes, and tubers, throughout the region, these societies adopted flexible strategies to adapt to life in a region prone to climatic change [ABSTRACT FROM AUTHOR]

This paper deals with the hydrological variability effects on the primary commercial fish species inhabiting the main channel and the floodplain of the large Paraná River in its middle reaches in Argentina. Analysing more than eight decades (1935–2016) of information on the most frequent and abundant commercial species in conjunction with hydrological levels and temperature, our results show that spring–summer floods of a certain magnitude (c. 6 m) and durations (> 80 days) are crucial for sustaining commercial fisheries. Moreover, the frequency of these floods was modulated by the decadal climatic fluctuations that have occurred over the past 100 years in the Paraná Basin. An insight into the probable incidence of some anthropogenic influences is also provided. [ABSTRACT FROM AUTHOR]

The purpose of this study is to analyse the credibility of the content of the message and that of news stories about environmental problems, comparing the cases of Argentina and Spain. Its novel contribution is that it also analyses credibility according to the generation to which the informant belongs. In Argentina, information was compiled by means of an online survey (NArgentina = 450), whereas in Spain the same survey was conducted by interviewers (NSpain = 493). Low levels of credibility were found for the contents of messages about environmental problems and also for the news stories and narratives generated around them. Significant differences were noted between Argentina and Spain in relation to the credibility of the content of the message (which is greater in Argentina) but not in the credibility of news stories about environmental problems. In contrast to expectations, no generational differences were found in the two countries with regard to either type of credibility. This paper discusses the implications of the lack of generational segmentation as well as the low levels of credibility detected. [ABSTRACT FROM AUTHOR]

The paper addresses vulnerability to Global Environmental Change of rural producers of Mendoza River basin, in Argentina. Vulnerability is a complex phenomenon that is generated at the intersection of environmental, social and economic dimensions. From a qualitative study based on in-depth interviews with producers of the study area, the paper explain the processes affecting actors (exposures / sensitivities) and the practices (adaptations) they develop to address these phenomena. The main idea is that hydroclimatological events act on a number of previous, long-term vulnerabilities defined by access to resources. Also it shows that resources are critical to the development of adaptive capacities, but finds that "availability of resources" and "capacity building" are not phenomena always related by a linear and direct causality. That is, sometimes the mere existence of resources is not enough to foster adaptive capacities. Noting some capacities gaps, the article identifies critical factors that could improve rural actors' capacities and could strengthen them to cope with future global climate events and other factors that affect their living conditions. [ABSTRACT FROM AUTHOR]

Patagonia features the most extensive glaciers of the Southern Hemisphere, excluding Antarctica, and a vast inventory of glacial landforms, so it is thought to have played a key role in (paleo)glacier studies since the late 19th century. However, no systematic attempts to characterize the specific research trends and the scientific community focused on Patagonian cryosphere have been conducted so far. To fill this gap, we analyzed the metadata associated to 305 articles compiled from the Web of Science database following a bibliometric approach covering the period between 1976 and 2020. Our results point to an irregular but net increase on the number of contributions on Patagonian (paleo)glaciers. Mass balance analyses based on satellite data of present-day glaciers and the reconstruction of past glacier activity by dating glacial landforms formed during the Last Glacial Termination, were the most addressed topics during the analyzed period. Patagonian (paleo)glacier studies are mostly published in generic Earth Sciences publications, followed by Quaternary and glaciological journals. Most of the studies were led by scientists from the United Kingdom, followed by Chile, Argentina and United States. In terms of collaborations, these studies can be divided into two main clusters, one composed by researchers from United States, Chile and Argentina institutions, and another mostly composed by British researchers. So far, the most prolific authors are nearly equally distributed in nationality, yet gender inclusion and international collaborations are still caveats that must be solved. Even though our query on the Web of Science missed highly influential (so-called) grey literature, such as local scientific journals and technical reports, the reviewed scientific literature unambiguously indicates that Patagonia is a privileged location for (paleo)glaciers studies worldwide and that it will continue offering vast opportunities to tackle critical questions related to global cryosphere and past-to-present climate changes. • Patagonia is a privilege site for studying present and past glacier dynamics and the evolution of climate changes at hemispheric and global scale. • Glacier dynamics during the 20th century and and the Last Glacial Termination are the most common topics addressed in past decades in the WOS. • Patagonian (paleo)glacier studies has contributed to the development or improvement of diverse analytical techniques. • United Kingdom, United States, Chile and Argentina produced the largest number of WOS-listed papers on (paleo)glaciers in past decades. • The related scientific community is fairly heterogeneous. Although, inclusion and international collaboration issues still need to improve. [ABSTRACT FROM AUTHOR]

Abstract: The coastal area of Samborombón Bay ends in a short cliff which, during the last decades, has been undergoing an increased retrogression of approximately 8.2m decade−1. The aim of this paper is to investigate whether this accelerated erosion can be related to an apparent wind-wave climate change, which has been recently reported for the Río de la Plata region. A numerical study with SWAN wave model for the period 1971–2005 drives to positive trends in the frequency of occurrence and heights of waves propagating from the E and ESE. Particularly, the number of cases of high waves from those directions displays a significant increment. In addition, previous papers have reported an increment of the frequency, height and duration of the storm surges in the Río de la Plata, so as a rise of the mean sea level in the region. It is concluded that the combination of those three factors acting together constitutes a powerful and effective mechanism which is likely responsible for the observed increasing erosion in Samborombón Bay. [Copyright &y& Elsevier]

Abstract: The investigation presented in this paper has three main objectives. The first one is to study, through a case study, if it is possible to acceptably predict the energy consumption of a massive residential free-running building, when the exact behavior of the occupants is unknown or actual indoor conditions are not monitored, assuming standard use and occupation schedules, for the dry climate of the Argentinean Northwest. The second objective of the paper is to detect the possible causes of differences between actual and predicted energy consumption through an exhaustive thermal monitoring and occupant''s behavior, in order to obtain an improved model of the building giving more accurate predictions of the energy consumption. The third objective is to analyze the effect on the annual energy consumption of changing the massive envelope by a lightweight one. The comparison of real and simulated consumptions under comfort conditions defined by ASHRAE Standard 55 shows that simulations overestimated the energy consumption for heating and cooling. The main causes were detected from the experimental monitoring, indicating a lower use of the air conditioning equipment than the supposed initially. Simulations were improved to consider actual use and occupation conditions. Finally, an annual simulation of the improved model performed by changing the envelope material to a lightweight one showed that energy consumption for heating was increased, while energy consumption for cooling was decreased. In an annual balance, the massive walls are preferable over lightweight ones in arid sunny climates as in the Argentinean Northwest, giving energy savings of around 25%. [Copyright &y& Elsevier]

This paper reviews recent progress made in our understanding of the functioning and variability of the South American Monsoon System (SAMS) on time scales varying from synoptic to long-term variability and climate change. The SAMS contains one of the most prominent summertime climate patterns in South America, featuring a strong seasonal variability in a region lying between the Amazon and the La Plata Basin. Much of the recent progress is derived from complementary international programs, such as the Monsoon Experiment South America (MESA), as well as from ongoing international programs such as the Large Scale Biosphere Atmosphere Experiment in the Amazon Basin (LBA) and the La Plata Basin (LPB) Regional Hydroclimate Project, which includes the CLARIS LPB Europe-South America Network for Climate Change Assessment and Impact Studies in La Plata Basin Project. The latter assesses atmosphere-land surface interactions, the role of land use changes and aerosols from biomass burning considered as sources of variability and change in the SAMS functioning, characteristics and behaviour. The SAMS region is particularly susceptible to variations of climate due to the importance of hydroelectricity generation and the agricultural base of local economies. Also addressed in this report are projections of climate change and extremes, which are important for impact and vulnerability assessments. This discussion includes the need to identify and understand important processes that control the monsoonal climate, how these processes may vary and change, and how they may interact with key societal sectors, including water resource management, hydroelectric generation, agriculture, and agribusiness. This paper reports on the major contributions of MESA to the knowledge of characteristics, functioning and variability of the SAMS, and is based on recent studies and publications, and can be considered as an update of a previous review by C. S. Vera et al. (2006a). Copyright © 2010 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

Favorable climate and soils for rainfed crop production, together with a relatively low population density, results in 70–90% of Argentina grain production being exported. No assessment to date has tried to estimate the potential for extra grain production for soybean, wheat and maize, which account for 78% of total harvested area, by yield gap closure on existing cropland area and its impact at a global scale. The objectives of this paper are (i) to estimate how much additional grain could be produced without expanding crop area by closing yield gaps in Argentina, (ii) to investigate how this production and yield gaps varies across regions and years, and (iii) to analyze how these inter-annual variations are related to El Niño—Southern Oscillation phenomenon (ENSO). Production increase on existing crop area was assessed for soybean, wheat and maize by quantifying the yield gap (Yg), that is, the difference between water-limited yield potential (Yw) and actual yield (Ya). A bottom-up approach was followed to estimate Yw and Yg, in which these parameters were first estimated for specific locations in major crop producing areas and subsequently up-scaled to country level based on spatial distribution of crop area and climate zones. Locally-calibrated crop simulation models were used to estimate Yw at each selected location based on long-term weather data and dominant soil types and management practices. For the analyzed period, the national level Yg represented 41% of Yw for both wheat and maize and 32% of the Yw for soybean. If farmers had closed Yg from these levels to 20% of Yw, Argentina could have increased soybean, wheat and maize production by a respective 7.4, 5.2, and 9.2 Mt, without expanding cropland area. This additional production would have represented an increase of 9%, 4%, and 9% of soybean, wheat, and maize global exports. This potential grain surplus was, however, highly variable because of the ENSO phenomenon: attainable soybean production was 12 Mt higher in favorable “El Niño” years compared with unfavorable “La Niña” years. Interestingly, Yg tended to be higher in wet years, suggesting that farmers do not take full advantage of years with favorable conditions for rainfed crop production. Regional variation in Yg was found in Argentina highlighting the usefulness of this work as a framework to target research and, ultimately, reduce gaps in areas where current yields are well below their potential. [ABSTRACT FROM AUTHOR]

Climatic change effects and the processes of urban growth caused environmental deterioration in the city of Buenos Aires. This situation alters the natural hydrological cycle and the hydrograph of floodwaters in urbanizing watersheds will modify, presenting flows higher peak and shorter rise times as it progresses. On the other hand, the global warming has caused an increase in mean annual precipitation and extreme values generated by storms of connective type, in the central region and North of Argentina. One of the possibilities to mitigate these effects is the implementation of extensive green roofs systems in terraces of buildings and houses built that help to reduce runoff factor. The objective of this paper was: to determine the reduction of surface runoff and water quality delivered for different types of green roofs with different types of vegetation implanted in normal rainfall in the city of Buenos Aires. The results of the study that was carried out along one year, showed that the retention capacity of the tested lots varied, depending upon precipitation, type of vegetation and coverage. For the range of 21 and 41 mm the retention ratesreached between 63% and 68%, with rainfall between 42 and 60 mm are observed percentages of retention from 31% to 39%. For the range of 61 to 80 mm the retention percentage was similarly to the range previously analyzed, 25% to 38%, and finally analyzing rainfall greater than 90 mm, the percentage of retention varies between 16% and 22%. The Aptenia cordifolia presented minors values of retention in all ranges except the first. The results of the test showed that green roofs system represent a good alternative in the integrated management of water runoff in urban watersheds. [ABSTRACT FROM AUTHOR]

This paper presents the first study of nonmarine ostracods recovered from the Danian of the upper Yacoraite Formation (Balbuena IV sequence) Salta Basin. Six species were identified: Ilyocypris triebeli , Ilyocypris argentiniensis , Neuquenocypris (Alleniella)? sp. 1; Neuquenocypris (Alleniella)? sp. 2; Penthesilenula sp. and four indeterminate species. The ostracod fauna shows fluctuations in abundance, diversity, and preservation associated with different phases of the paleolake evolution. This distribution, clearly delineated by the depositional facies, corroborates previous geochemical analyses and high-resolution sequence stratigraphy developed for the section. In general, the most abundant occurrences of ostracods coincide with high-frequency transgressive tracts of the lake system, which form long-term wettest interval of the upper Yacoraite Formation. • First study with ostracods for the Balbuena IV sequence of the Yacoraite Formation, Salta Basin, Argentina. • Six nonmarine ostracods species are identified. • Temporal distribution of ostracods is in agreement with U/Pb radiometric dating. • Ostracod abundance is correlated with the climatic fluctuations of the dry and wet periods of the paleolake. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a land-use modelling framework is presented combining empirical and theory-based modelling approaches to determine economic potential of biofuel production avoiding indirect land-use changes (iLUC) resulting from land competition with other functions. The empirical approach explores future developments in food and feed production to determine land availability and technical potential of biofuel production. The theory-based approach assesses the economic performance of biofuel crops on the surplus land in comparison with other production systems and determines the economic potential of biofuel production. The framework is demonstrated for a case study in Argentina to determine the development of biofuel potential from soy and switchgrass up to 2030. Two scenarios were considered regarding future developments of productivity in agriculture and livestock production. It was found that under a scenario reflecting a continuation of current trends, no surplus land is expected to become available. Nevertheless, the potential for soybean biodiesel is expected to keep increasing up to 103PJ in 2030, due to the existence of a developed agro-industrial sector jointly producing feed and biodiesel. In case large technological developments occur, 32Mha could become available in 2030, which would allow for a technical potential of 472PJ soybean biodiesel and 1445PJ switchgrass bioethanol. According to the economic assessment, an economic potential of 368PJ of soy biodiesel and 1.1EJ switchgrass bioethanol could be attained, at a feedstock production cost of 100–155 US$/ton and 20–45 US$/ton, respectively. The region of southwest Buenos Aires and La Pampa provinces appeared to be particularly promising for switchgrass. The ability of jointly assessing future developments in land availability, technical and economic potential of biofuel production avoiding iLUC and spatial distribution of viable locations for growing biofuel crops means that the proposed framework is a step forward in assessing the potential for biofuel production that is both economically viable and sustainably produced. [Copyright &y& Elsevier]

Abstract: Solar radiation is the most important source of renewable energy in the planet; it's important to solar engineers, designers and architects, and it's also fundamental for efficiently determining irrigation water needs and potential yield of crops, among others. Complete and accurate solar radiation data at a specific region are indispensable. For locations where measured values are not available, several models have been developed to estimate solar radiation. The objective of this paper was to calibrate, validate and compare five representative models to predict global solar radiation, adjusting the empirical coefficients to increase the local applicability and to develop a linear model. All models were based on easily available meteorological variables, without sunshine hours as input, and were used to estimate the daily solar radiation at Cañada de Luque (Córdoba, Argentina). As validation, measured and estimated solar radiation data were analyzed using several statistic coefficients. The results showed that all the analyzed models were robust and accurate (R 2 and RMSE values between 0.87 to 0.89 and 2.05 to 2.14, respectively), so global radiation can be estimated properly with easily available meteorological variables when only temperature data are available. Hargreaves-Samani, Allen and Bristow-Campbell models could be used with typical values to estimate solar radiation while Samani and Almorox models should be applied with calibrated coefficients. Although a new linear model presented the smallest R 2 value (R 2 = 0.87), it could be considered useful for its easy application. The daily global solar radiation values produced for these models can be used to estimate missing daily values, when only temperature data are available, and in hydrologic or agricultural applications. [Copyright &y& Elsevier]

Abstract: The Tandilia range is a discontinuous series of hills and valleys located at the central area of the Pampean region (Argentina). The process of human settlement reached in this zone the highest population densities and reoccupation levels of Southern South America, developing under the strongly changing climatic conditions that characterized the Pleistocene–Holocene transition. This paper analyzes the geoarchaeological and paleoenvironmental record of the Pleistocene–Holocene transition (c. 9400–10,500 14C BP) recovered from cave and rockshelter sedimentary successions of the Tandilia range. The analysis of several lines of evidence (stratigraphic, geoarchaeological, archaeological, zooarchaeological, and paleobotanical), suggests that a cold arid to semi-arid climate characterized the late Pleistocene (c. 10,500 BP), and changed abruptly to warmer conditions towards the beginning of the Post-Glacial Period. As a consequence of this climatic amelioration, the populations inhabiting the Tandilia range would have been benefited by a higher availability of resources, which could explain the higher levels of site density and reoccupation found in the area during this period. [Copyright &y& Elsevier]

Abstract: In recent years, there has been an increasing interest in the study of climate change effects on plant phenology. However, the effects of other more localized components of global change such as land degradation have been almost completely ignored. In this paper we evaluate the phenological patterns of 10 plant species at three sites with contrasting levels of land degradation due to overgrazing in the Patagonian Monte, Argentina, and their relationship with plant morphology, browsing intensity, and plant competition. Plant phenology differed among sites in eight species, but plant responses were species-specific. In six species the dormancy and senescence periods were shorter indicating longer growing cycles at high degradation than at low degradation site. Generally, plants growing at high degradation site present longer and frequently incomplete vegetative periods and shorter and less dominant reproductive periods than those at low degradation site. However, in some species the duration of reproductive periods was greater in the high degradation site. Plant size (i.e. height, area, and/or internal cover) affected plant phenology in seven species. In contrast, browsing and neighbor''s cover were rarely related to plant phenology. Our results suggest that other global change components such as land degradation may affect plant phenology. [Copyright &y& Elsevier]

Abstract: This paper contributes to the literature that analyses the determinants and measurement of Technological Capabilities (TCs) with empirical evidence on Argentina, Brazil and Chile. Based on the World Bank''s Investment Climate database, the study covers firms from the manufacturing sector. We first construct a Capability Score to provide a preliminary measure of Technological Capabilities at the firm level. We then test it econometrically to explore the determinants of TCs and exports and evaluate their reciprocal relationship through a Two Stage Probit. Our results show that exports and TCs significantly and positively influence each other in some of these countries. [Copyright &y& Elsevier]

Abstract: The aim of this paper is to present the partial trends of rainy days and total precipitation in Córdoba Province, Argentina, during the period 1960–2010 and the full range of precipitation for the Córdoba Observatory station, which has the longest measurement record in Argentina, 1873–2010, and to show the relationship between these variables and solar activity. A strong association is shown between break points when the trend changes for both the number of rainy days and the total precipitation, and the occurrence of maxima in the sunspot cycle, indicating that these variables are modulated by the solar Hale cycle and probably by the influence of cosmic rays. [Copyright &y& Elsevier]

Abstract: Maize responses to individual management factors have been widely investigated but studies of higher-order interactions involving multiple factors are rare. This paper investigates the responses of grain yield and water use efficiency of rainfed maize to sowing date, stubble condition, hybrids of contrasting cycle length, soil depth and their interactions, and how these responses are affected by El Niño – Southern Oscillation (ENSO) phenomenon. Grain yield and water balance were modelled with CropSyst using 33 years of weather data for eight locations in an east–west transect in the Southern Pampas of Argentina. Modelled grain yield decreased westward, in parallel with decreasing rainfall. Southern Oscillation Index (SOI) discriminated crop season rainfall and grain yield, with lower rainfall and grain yield for SOI phase Consistently Positive (CP) and higher rainfall and grain yield for SOI phase Consistently Negative (CN). Differences in grain yield between stubble and bare soil were constant across location. High available water, as related to soil depth, increased grain yield across the transect. The effect of sowing date and stubble varied with SOI phase; for CN, highest grain yields were obtained with early sowing whereas for CP grain yield showed no correlation with sowing date. Yield differences between bare soil and stubble conditions were higher under CP than under CN, reflecting the positive effect of stubble in years with rainfall below average. Water use efficiency (WUE=yield per unit evapotranspiration) averaged 19.0kgha−1 mm−1 for soils with stubble and 16.5kgha−1 mm−1 for bare soil. We conclude that SOI provides an agronomically meaningful predictor of seasonal conditions that can be used to estimate crop production and manage risk by adjusting key management practices. [Copyright &y& Elsevier]

Abstract: This paper analyzes the spatial organization of two layers corresponding to the first half of the Middle Holocene from the Hornillos 2 rockshelter (Susques, Jujuy Province). Some important issues taken into account are the good preservation of the site and the sedimentary deposition processes which coincide with paleoclimate aspects. Correlation of different archaeological lines of evidence allows interpretation of the connection between several activity areas and their occupational intensity. There is a trash heap related to a short occupation period at the beginning of the Middle Holocene and a main zone of intense activity ca. 6200 yrs BP. These facts are in accordance with the archaeological expectations proposed for certain periods of the Middle Holocene. [Copyright &y& Elsevier]

The Chaco plain region in Argentina is located in the north of the country and east of Los Andes where the main activity is the agriculture. As such activity is highly affected by interannual rainfall variability, the influence of some of the principal atmospheric and oceanic forcing is investigated in this paper. Results show that the factors which affect precipitation highly depend on the season and the subregion. The position of the South Atlantic Height and the sea surface temperature in the coast of southern Brazil and Buenos Aires seem to be the factors that affect rainfall, all over the year. The El Niño-Southern Oscillation phenomenon affects summer and spring rainfall and the Southern Annular Mode involves spring precipitation but both only in the east of the study region. Furthermore, enhanced convection in Central Brazil, mainly influences autumn and spring rainfall. [ABSTRACT FROM AUTHOR]

Abstract: The recently excavated Paso Otero 4 site is located within the Paso Otero archaeological locality (Necochea District, Pampean Region). The site is characterized by the presence of a great variety of archaeological materials and a rich and complex stratigraphic record which allows use of an interdisciplinary approach. The objective of this paper is to present the results of the geoarchaeological, palynological, phytolith, and diatom analyses in order to reconstruct the paleoenvironmental conditions for the final Late Pleistocene through Holocene. These lines of research allow inference of paleoenvironmental and palaeoclimatic conditions on both local and regional scales. At the site, the Río Salado Member (Unit 2), where the archaeological deposit is buried, underwent sudden and fluctuating changes in water availability conditions, although the setting was basically characterized by calm depositional processes within and along the margins of interconnected lagoons. Paleoclimatic reconstructions indicate the existence of abrupt climatic changes throughout the sequence. Early Holocene human occupations took place under regionally temperate-warm climates while the end of the Middle Holocene witnessed cold and arid or cold temperate climates. In general terms, paleoenvironmental conditions inferred for Paso Otero 4 are in accordance with regional reconstructions proposed for the Pampas. [Copyright &y& Elsevier]

Summary: In recent times, significant areas of the Northeastern Argentine (NEA) have been affected by climatic fluctuations which have caused serious damages in ecosystems and people’s livehoods, both by floods and droughts. This has mainly occurred in the Santa Fe Province, having a great impact on the underlying unconfined aquifer. This paper analyzes the relationships between meteorological variability and water table levels in the context of climate variability and climatic change in the lower Carcarañá river experimental basin (about 4700km2), located in the Santa Fe Province. The goal of the study is to obtain long-term (interannual) predictions of water table levels in the region. The methodology used responds to a hypothetical conception of the temporal series having a signal formed by random components with characteristics of white noise. Singular Spectral Analysis (SSA), among other non-parametric techniques were used to identify fluctuations and trend changes in climatic time-series. These characteristics provide valuable information for the evaluation of climatic evolution and for the detection of variations in this evolution, suggesting a climatic change either by natural mechanisms or by anthropogenic impacts. A positive trend in precipitation is found throughout the studied region with water table levels showing a similar spatial–temporal behavior. The SSA gives significant periodicities between 3 and 8years showing a possible link between El Niño-Southern Oscillation (ENSO) phenomenon and precipitation and water table levels. The periodicities linked with ENSO are always present and the structures of the series are similar for the different studied periods. The results obtained, even if they are experimental constitute a first approximation. In general, they are promising, since the generated basis will enable to face further and more complex stages. [Copyright &y& Elsevier]

Abstract: The Andean piedmont of Mendoza is a semiarid region covered by extensive and partially vegetated dune fields consisting of mostly inactive aeolian landforms of diverse size and morphology. This paper is focused on the San Rafael plain (SRP) environment, situated in the distal Andean piedmont of Mendoza (34° 30′S), and reports the sedimentology and OSL chronology of two representative exposures of late Quaternary deposits, including their paleoenvironmental and paleoclimatic significance. Eleven facies, including channel, floodplain, fluvio–aeolian interaction, and reworked pyroclastic and aeolian deposits, were described and grouped into two facies associations (FA1 and FA2). FA1 was formed by unconfined sheet flows, minor channelized streams and fluvial–aeolian interaction processes. FA2 was interpreted as aeolian dune and sand-sheet deposits. OSL chronology from the SRP sedimentary record indicates that between ca. 58–39ka and ca. 36–24ka (MIS 3), aggradation was governed by ephemeral fluvial processes (FA1) under generally semiarid conditions. During MIS 2, the last glacial maximum (ca. 24–12ka), a major climatic shift to more arid conditions is documented by significant aeolian activity (FA2) that became the dominant sedimentation process north of the Diamante–Atuel fluvial system. The inferred paleoenvironmental conditions from the SRP sections are in broad agreement with regional evidence. [Copyright &y& Elsevier]

The study of the temporal-spatial variability of dry sequences and the probability of their occurrence are particularly important in understanding the impact of climate change on droughts. This paper analyses the different properties of dry sequences, focussing on extreme condition, analysing their degree of spatial coherence, and their temporal variability. For the study, daily precipitation data are used for the period 1961-2000 throughout Argentina. The region north of 40°S is divided in two from the meridian of 63°W with highly differentiated 'dry' properties. The eastern region is more homogeneous where mean dry sequences last less than six days and long sequences of about 60 days. The Andean region shows a marked east-west gradient in any of the above properties, with extreme values of over 10 days (mean sequences) and 150 days (the longest sequences). At the seasonal level the above properties reflect a differential pattern according to the time of year under study. In the case of summer, when the dry sequences can be more harmful to crops, the maximum duration in the Pampa region can extend to about 25 days. Owing to the problems that dry sequences of over 30 days can produce in the different ecosystems and based on the above findings, the temporal-spatial variability is analysed, and a variability over the years, together with a progressive decrease in the occurrence of such events, is found. The study of extreme dry events provides useful tools that can be applied to different hydrological and agricultural needs. Furthermore, our climatological findings help validate climate models. Copyright © 2010 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

The Kyoto Protocol, is the first legal instrument with a compromise to reduce the production of greenhouse effect's Gases. In Argentinean legislation the United Nation's Convention as well as the Kyoto Protocol are included in internal laws in the Law 24.295 and the law 25.438. The objective of this paper is to review the origins of these two international instruments; their incorporation to the Argentinean internal law; and to determine the state of the art of its application and the effectiveness of the Argentinean laws. [ABSTRACT FROM AUTHOR]

Abstract: This paper evaluates the chronology of the last glacial cycle and deglaciation in the Lago Pueyrredón valley of central Patagonia, 47.5° S, Argentina. The valley was a major outlet of the former Patagonian Ice Sheet and the moraines that record its fluctuations are an important proxy record of climate change in southern South America. Such moraines are well-preserved in the Lago Pueyrredón valley owing in part to the semi-arid environment east of the mountain front. Here, we provide the first direct chronology for the age of the “Rio Blanco” moraine system by utilizing cosmogenic-nuclide surface exposure ages. Boulders on the moraines give 10Be exposure ages that indicate the Last Glacial Maximum (LGM) maximum extent occurred by 27–25ka. Subsequent advances occurred at 23–22ka, 20–18ka, and ca. 18–17ka. Initial deglaciation began after ca. 18–17ka and was interrupted as evidenced by the Lago Columna moraines up-valley. Subsequently the outlet glaciers occupying both the Lago Pueyrredón basin (Chilean name: Lago Cochrane) and the Lago Buenos Aires basin (Chilean name: Lago General Carrera) to the north, rapidly retreated more than 80km at around 16.5–15ka. The timing of the LGM maximum extent and the onset of deglaciation occurred broadly synchronously throughout Patagonia. Deglaciation resulted in a series of interconnected glacier-dammed lakes in the region that initially drained toward the Atlantic Ocean and later drained to the Pacific Ocean as a consequence of disintegrating ice in the Andes. [Copyright &y& Elsevier]

Abstract: Lakes are key sites for studying paleoclimates. Llancanelo Lake (southern Mendoza Province, western Argentina) is an endoreic, highly saline water body located in the southern extreme of a tectonic basin, the Central or Huarpes Depression. The lake is located between the Andean Cordillera, San Rafael Block and Payenia Volcanic Field. The lake evolved as a major regional depocenter during the Pliocene-Quaternary, hence it contains important thicknesses of intra and extra basinal clastic and evaporitic sediments mainly dominated by volcaniclastic products. The main conditioning factors in the lake evolution were arc and back-arc volcanism as well as climatic changes. Geomorphological and sedimentary evidence supports the hypothesis that the lake was in past times larger than in present days. This paper estimates the lake’s former extension on the western lacustrine plain using electromagnetic induction (EMI) and geoelectricity (Multielectrode Resistivity Meter) surveys, as well as shallow wells, along an 8km long transect perpendicular to the lake’s western shoreline. The geophysical and sedimentological information, as well as microfaunal studies, lab analysis and petrographic/EDAX determinations, support the presence, in the subsoil, of a lacustrine sequence at least 30m thick composed mainly of volcaniclastic sediments. Volcanic eruptions and climatic changes influenced the evolution of the lake, producing intercalations in the lacustrine sedimentary sequences of ash layers, evaporites, soils, and eolian and swamp deposits. [Copyright &y& Elsevier]

Abstract: This paper documents the main features of climate and climate variability across the Monte Desert for the Last Glacial Maximum, the Glacial–Interglacial transition, and the Holocene on the basis of proxy records and for the 20th century using instrumental observations. The climate in the Monte is determined by interactions between regional physiography and atmospheric circulation in the 25–45°S sectors of South America. Although arid and semi-arid conditions prevail across the Monte, its large latitudinal extent and complex topography introduce many particularities at local scales. Paleoclimatic records and model simulations of past climates suggest significant variations in the atmospheric circulation, temperature and rainfall patterns since the Last Glacial Maximum. High-resolution proxy records east of the Andes support the existence of complex climatic patterns with similar temperature changes across the whole region but opposite precipitation variations between subtropical and mid-latitude sectors in the Monte during the past millennium. The present-day climate is depicted in terms of the space and time variability of the near-surface temperature, rainfall and tropospheric wind patterns. Uneven temperature trends over the Monte were recorded for two separate (1920–44 and 1977–2001) global warming periods in the 20th century. Additional warming evidence in the region is provided by extreme temperature records. The non-homogeneous regional pattern of precipitation shows a positive long-term increase between 30 and 40°S during the interval 1985–2001. Ensemble of climate experiments accomplished with general circulation models provide the most likely changes in temperature and rainfall to occur by the end of this century in relation to present climate. Temperature increases, larger in summer than in winter, will be concurrent with more abundant precipitations in summer, but almost no changes or even small reductions in winter across the Monte. [Copyright &y& Elsevier]

Abstract: The main goal of this paper is to highlight regional and temporal variation in the presence and exploitation of faunal resources during the Late Pleistocene and Early Holocene (ca. 12000–7000 uncalibrated 14CyrBP) in the Pampean region (Argentina, South America). The main issues discussed are a summary of archeological and zooarchaeological evidence (sites, location, chronology, lithic technology, faunal distribution and diversity, etc.) both on regional and areal scales. The topics included in order to characterize subsistence strategies are the climatic changes that operated on and influenced the species, differential species extinction and survival, exploited species diversity, procurement and processing techniques, and intensity of faunal exploitation. It is proposed that the Late Pleistocene–Early Holocene period is characterized by a generalized regional economy, as has also been recently proposed for North America. In general terms, a broad spectrum of resources would have been exploited by humans as suggested by the presence and diversity of consumed species. Given the fluctuating climatic conditions during the Pleistocene-Holocene transition, a subsistence pattern composed of a broad diet would have been a suitable strategy to promote in unstable environments. Both taxonomic diversity and richness are greater when compared with the following time period (Middle Holocene), characterized by a specialized regional economy. [Copyright &y& Elsevier]

Water resources management and agriculture planning models require a statistical synthesis of some rainfall features, in particular those representing dry atmospheric conditions. The bigger the basin, the more important these features become, as is the case of the La Plata Basin LPB.This paper focuses on the precipitation variability in the large LPB in South America, analysing the number of months per year with low rainfall and the sequences of months with low rainfall, their theoretical distributions and stability, which are needed as input for the models mentioned above.Long time series are used to analyse the lowfrequency variability and the relative importance of decadal variability. Changes are evident in the number of months per year with low rainfall, with a decrease of about 20 in the period after 1970.Theoretical distribution models binomial and geometric are fitted to these empirical distributions, and the regional variability of the fitting parameters is shown. In practically the entire region, the goodnessoffit of the two theoretical models considered is statistically satisfactory.The temporal variability of the parameters of the theoretical binomial p and geometric α distributions is analysed, in excluding subperiods of 10 and 5 years, respectively. The results show lowfrequency variability overlapped on a decadal variability, with low homogeneous regional behaviour.The distribution models have proven to be efficient for frequency adjustments of the rainfall properties studied. These results are an acceptable and necessary input to decision models in LPB. They also make it possible to infer effects of climate change. Copyright © 2008 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

Several studies show that the El Niño-Southern Oscillation (ENSO) is an important factor in determining interannual rainfall variability in South America. This signal is detected in the region including Northeastern Argentina, Uruguay and part of southern Brazil, in the form of excessive rains and big floods in the regional rivers. To check that this relationship was similar in the past the objectives of this paper were to construct a time series of large floods in the Paraná River region from documentary records, during the sixteenth to eighteenth centuries, and to evaluate the relationship between that historical record of extreme floods, the ENSO documentary evidence (Ortlieb, The Documented Historical Record of El Niño Events in Perú: An Update of the Quinn Record (Ortlieb, sixteenth through nineteenth centuries, Diaz and Markgraf, (eds.), El Niño and the southern oscillation. Multiscale variability and global and regional Impacts. Cambridge University Press, pp. 207-295, 2001; Quinn and Neal, The historical record of El Niño events, Bradley and Jones (eds.), Climate since a.d. 1500, Routledges, pp. 623-648, 1992) and the temperature index of the Pacific Ocean (Mann ME et al., Global temperature patterns in past centuries: an interactive presentation, IGBP pages/world data center for paleoclimatology data contribution series #2000-075. NOAA/NGDC Paleoclimatology Program, Boulder CO, USA, 2000). Considering that the period 1904-2000, where 11 out of 16 floods occurred during El Niño events, it can be concluded that the proportion of years with exceptional flow volume in the Paraná River in years with El Niño events in the seventeenth and eighteenth centuries was relatively lower than that of the twentieth century. The reason for this difference is discussed. [ABSTRACT FROM AUTHOR]

The snowpack in the central Andes (30°–37°S) is the primary source for streamflow in central Chile and central-western Argentina, but few published studies are available on snowpack variability in the region. This paper develops the first regional snowpack series (1951–2005) from Chilean and Argentinean snow course records. This series shows a strong regional signal, marked interannual variability, and a positive, though nonsignificant, linear trend. Correlations with local precipitation and temperature records reveal a marked association with conditions in central Chile. High snow accumulation is generally concurrent with El Niño events in the tropical Pacific, but only 5 of the 10 driest years coincided with La Niña events. Evaluation of 500-hPa geopotential height anomaly maps during extreme snow years highlights the crucial significance of tropospheric conditions in the subtropical and southeast Pacific in modulating snowfall. Correlations with gridded SST and SLP data and multiple regressions with large-scale climatic indices corroborate a Pacific ENSO-related influence largely concentrated during the austral winter months. This hampers the predictability of snowpack before the onset of the cold season. Annual and warm-season river discharges on both sides of the cordillera are significantly correlated with the regional snowpack record and show positive linear trends over the 1951–2004 common period, probably related to a greater frequency of above-average snowpacks during recent decades. Future demand and competition for water resources in these highly populated regions will require detailed information about temporal and spatial variations in snow accumulation over the Andes. The results indicate that the relationships between snowpack and atmospheric circulation patterns prior to the winter season are complex, and more detailed analyses are necessary to improve prediction of winter snowfall totals. [ABSTRACT FROM AUTHOR]

There is evidence of the increasing economic losses from extreme natural events during the last decades. These facts, thought to be triggered by environmental changes coupled with inefficient management and policies, highlight particularly exposed and vulnerable regions worldwide. Argentina faces several challenges associated with global environmental change and climate variability, especially related to water resources management including extreme floods and droughts. At the same time, the country's production capacity (i.e. natural resource-based commodities) and future development opportunities are closely tied to the sustainable development of its natural resource endowments. Given that vulnerability is registered not only by exposure to hazards (perturbations and stresses), but also resides in the sensitivity and resilience of the system experiencing such hazards, Argentina will need to improve its water management capacities to reduce its vulnerability to climate variability and change. This paper presents the basic components of the vulnerability analysis and suggests how it can be used to define efficient water management options. [ABSTRACT FROM AUTHOR]

In recent decades, multiple flood events have had a devastating impact on soybean production in Argentina. Recent advances suggest that the frequency and intensity of destructive flood events on the Argentinian Pampas will increase under pressure from climate change. This paper provides bottom-up insight into the flood risk for soybean production systems under climate change and the suitability of adaptation strategies in two of the most flood-prone areas of the Pampas region. The flood risk perceptions of soybean producers were explored through interviews, translated into climatic indicators and then studied using a multi-model climate data analysis. Soybean producers perceived the present flood risk for rural accessibility to be of the highest concern, especially during the harvest and sowing seasons when heavy machinery needs to reach soybean lots. An analysis of climatic change projections found a rising trend in annual and harvest precipitation and a slight drying trend during the sowing season. This indicates that the flood risk for harvest accessibility may increase under climate change. Several adaptation strategies were identified that can systemically address flood risks, but these require collaborative action and cannot be undertaken by individual producers. The results suggest that if cooperative adaptation efforts are not made in the short term, the continued increase in flood risk may force soybean producers in the case study locations to shift away from soybean towards more robust land uses. [ABSTRACT FROM AUTHOR]

The apparently regular and favourable climate that characterizes the Holocene as an interglacial period shows, however, important climatic instability well documented in the Northern Hemisphere. These fluctuations from colder to warmer or wetter to drier affected both biodiversity and human societies in the last 12,000 years, although the impact in Southern America is still poorly known. We are here investigating the biodiversity of small mammal faunas, more sensitive to climatic changes than large mammals, combining taphonomic and palaeoecological data in the Argentine Pampas to better understand the global nature and effect of these Holocene climatic fluctuations. This paper is pioneering applying in this region palaeoecological methodologies practised in European sites, such as the chorotype classification and biomes overlap analyses. The Pampean Region is an ecotone with a confluence of three climatic regions where any change in climatic conditions should be easily detected. Our results, based on the palaeoecological requirements of small mammals, do not indicate severe changes, and most of the sites show climatic stability except for one of them, in which a possible trend towards present conditions (temperate/humid) can be inferred. • New palaeoecological methodologies are applied to the Pampean Region. • Microfauna is the best climatic indicator if multiproxy interpretations are considered. • Cave vs. open-air sites influence the composition of fossil small mammal assemblages. • Human activities in the past can distort palaeoecological interpretations. • Noticeable climatic events in the Northern hemisphere are soften/absent in the South. [ABSTRACT FROM AUTHOR]

Shallow lakes are distinctive aquatic ecosystems of the Pampean region. In this paper, climatic, morphometric and chemical-environmental aspects of six lacustrine bodies of the Salado River basin, Buenos Aires, are analyzed. The climatic variability of the region was estimated and linked to the behavior of each water body during the studied period (2017–2018); precipitations displayed deviations from the mean values, with periods of deficit in spring and summer, and excess in autumn. The analysis of satellite images showed a group of lakes with very low variation of the morphometric parameters because they have gates that keep the water level constant. On the contrary, those without anthropic intervention displayed a greater morphometric variability, since the water levels have been directly linked to local weather fluctuations. From a chemical-environmental perspective, changes were observed both at the regional (p = 0.015) and local (p = 0.0014) levels. Differences among sites cannot be characterized by a single variable but by a set of them. The dominant cation in the Pampean shallow lakes is the Na+ coming from the contact of groundwater with loessic sediments. Lakes showed a particular anionic dominance that not following a seasonal but a particular pattern. These are mainly linked to the characteristics of the substrate (presence of marine sediments or gypsum deposits). The great vulnerability of these environments to global and regional climatic changes, anthropic modifications and a large number of shallow lakes in the area, allow finding different scenarios (geomorphological, ecological, hydrogeological, etc.) to assess their vulnerability and predict their behavior against future climate scenarios in an economically important area for Argentine. Image 1 • Shallow lakes morphometric characteristics are related to their geomorphologic context. • Sodium is the main cation, mainly as a result of Pampean loess degradation. • Presence of different anions and water types are conditioned by lake sediments. • Local rainfall determinate water levels in unmodified systems. • In anthropised sites, hydrological and morphological parameters are less variable. [ABSTRACT FROM AUTHOR]

The objective of the present paper is to recognize and reconstruct, from the analysis of pollen recovered from sedimentary cores, the predominant plant communities and their variations during the Holocene in Corrientes Argentina, in order to infer changes in climatic conditions, vegetation and paleoenvironmental evolution in the northeast of Argentina. For this study, lakes located in the central region of Corrientes province were selected, comprising part of the western margin of the Iberá Wetland. The palynological analysis of the paleocommunities shows, in a first stage of the mid Holocene, the predominance of marsh grasslands and hygrophilous communities that indicates humid to sub‐humid environmental conditions. In a later stage of the mid Holocene, the paleocommunities show a characteristic association of wetlands, which together with the presence of Typha sp., would indicate sub‐humid to humid conditions and waterlogged or flooded soils with slow‐moving water. For the late Holocene, the paleocommunities show, initially, the presence of a grass‐dominated herbaceous steppe, indicating environmental disturbances, which in the fossil record could reflect the combination of intense wind action under a dry climate. In a later stage, the frequency and variety of species characteristic of humid environments increase, dominated by marshy‐herbaceous species, in addition to the development of the hygrophilous forest. Consequently, since the mid Holocene, the main climate factors responsible for the observed changes in wetland conditions were the location and intensity of the Atlantic and Pacific anticyclones in addition to changes in sea level. These forces mainly affected the distribution of precipitation, causing significant changes in the vegetation communities. [ABSTRACT FROM AUTHOR]