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Refugia-based conservation offers long-term effectiveness and minimize uncertainty on strategies for climate change adaptation. We used distribution modelling to identify climate change refugia for 617 terrestrial mammals and to quantify the role of protected areas (PAs) in providing refugia across South America. To do so, we compared species potential distribution across different scenarios of climate change, highlighting those regions likely to retain suitable climatic conditions by year 2090, and explored the proportion of refugia inside PAs. Moist tropical forests in high-elevation areas with complex topography concentrated the highest local diversity of species refugia, although regionally important refugia centers occurred elsewhere. Andean-Amazon forests contained climate change refugia for more than half of the continental species' pool and for up to 87 species locally (17 × 17 km 2 grid cell). The highlands of the southern Atlantic Forest also included megadiverse refugia for up to 76 species per cell. Almost half of the species that may find refugia in the Atlantic Forest will do so in a single region-the Serra do Mar and Serra do Espinhaço. Most of the refugia we identified, however, were not in PAs, which may contain <6% of the total area of climate change refugia, leaving 129-237 species with no refugia inside the territorial limits of PAs of any kind. Our results reveal a dismal scenario for the level of refugia protection in some of the most biodiverse regions of the world. Nonetheless, because refugia tend to be in high-elevation, topographically complex, and remote areas, with lower anthropogenic pressure, formally protecting them may require a comparatively modest investment., (© 2023 Society for Conservation Biology.)

Global warming has significantly altered fish distribution patterns in the ocean, shifting towards higher latitudes and deeper waters. This is particularly relevant in high-latitude marine ecosystems, where climate-driven environmental changes are occurring at higher rates than the global average. Species Distribution Models (SDMs) are increasingly being used for predicting distributional shifts in habitat suitability for marine species as a response to climate change. Here, we used SDMs to project habitat suitability changes for a range of high-latitude, pelagic and benthopelagic commercial fish species and crustaceans (10 species); from 1850 to two future climate change scenarios (SSP1-2.6: low climate forcing; and SSP5-8.5: high climate forcing). The study includes 11 Large Marine Ecosystems (LME) spanning South America, Southern Africa, Australia, and New Zealand. We identified declining and southward-shifting patterns in suitable habitat areas for most species, particularly under the SSP5-8.5 scenario and for some species such as Argentine hake (Merluccius hubbsi) in South America, or snoek (Thyrsites atun) off Southern Africa. Geographical constraints will likely result in species from Southern Africa, Australia, and New Zealand facing the most pronounced habitat losses due to rising sea surface temperatures (SST). In contrast, South American species might encounter greater opportunities for migrating southward. Additionally, the SSP5-8.5 scenario predicts that South America will be more environmentally stable compared to other regions. Overall, our findings suggest that the Patagonian shelf could serve as a climate refuge, due to higher environmental stability highlighting the importance of proactive management strategies in this area for species conservation. This study significantly contributes to fisheries and conservation management, providing valuable insights for future protection efforts in the Southern Hemisphere., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Gridded precipitation (PRP) data have been largely used in diagnostic studies on the climate variability in several time scales, as well as to validate model results. The three most used gauge-based PRP datasets are from the Global Precipitation Climatology Centre (GPCC), University of Delaware (UDEL), and Climate Research Unit (CRU). This paper evaluates the performance of these datasets in reproducing spatiotemporal PRP climatological features over the entire South America (SA) for the 1901–2015 period, aiming to identify the differences and similarities among the datasets as well as time intervals and areas with potential uncertainties involved with these datasets. Comparisons of the PRP annual means and variances between the 1901–2015 period and the non-overlapping 30-year subperiods of 1901–1930, 1931–1960, 1961–1990, and the 25-year subperiod of 1991–2015 for each dataset show varying means of the annual PRP over SA depending on the subperiod and dataset. Consistent patterns among datasets are found in most of southeastern SA and southeastern Brazil, where they evolved gradually from less to more rainy conditions from 1901–1930 to the 1991–2015 subperiod. All three datasets present limitations and uncertainties in regions with poor coverage of gauge stations, where the differences among datasets are more pronounced. In particular, the GPCC presents reduced PRP variability in an extensive area west of 50° W and north of 20° S during the 1901–1930 subperiod. In monthly time scale, PRP time series in two areas show differences among the datasets for periods before 1941, which are likely due to spurious or missing data: central Bolivia (CBO), and central Brazil (CBR). The GPCC has less monthly variability before 1940 than the other two datasets in these two areas, and UDEL presents reduced monthly variability before 1940 and spurious monthly values from May to September of the years from 1929 to 1941 in CBO. Thus, studies with these three datasets might lead to different results depending on the study domain and period of analysis, in particular for those including years before 1941. The results here might be relevant for future diagnostic and modelling studies on climate variability from interannual to multidecadal time scales. [ABSTRACT FROM AUTHOR]

Climate change has been unequivocally linked to human impact. Human actions have affected the environment and its inhabitants in a variety of ways around the globe and the response of various species can provide insight to what the future holds if we do not begin to mitigate the impacts of climate change. Monkeys are especially important as they function as ecosystem engineers, having a significant impact on plants and other animals in their habitats. Despite their importance, primates in South America and Africa remain understudied, yet are especially at risk as these regions have already undergone significant habitat loss. These regions are also Biodiversity Hotspots with the highest numbers of primate species on Earth. This systematic literature review assesses the current state of knowledge on how monkeys have changed their behavior in response to anthropogenic climate change. For this review, we scanned 3,461 titles, and 100 papers were read in full; seven of 100 papers provided relevant data. These studies primarily reported fertility changes and food substitutions when species were exposed to harsh conditions. The paucity of results from this review demonstrates that more research is needed on this topic. The effects of climate change on primates and their habitats must also be studied in conjunction with other anthropogenic stressors. As humans encroach on wildlife habitats, policies must be implemented to protect the habitats that are still viable. [ABSTRACT FROM AUTHOR]

Manual outdoor work is essential in many agricultural systems. Climate change will make such work more stressful in many regions due to heat exposure. The physical work capacity metric (PWC) is a physiologically based approach that estimates an individual's work capacity relative to an environment without any heat stress. We computed PWC under recent past and potential future climate conditions. Daily values were computed from five earth system models for three emission scenarios (SSP1-2.6, SSP3-7.0, and SSP5-8.5) and three time periods: 1991-2010 (recent past), 2041-2060 (mid-century) and 2081-2100 (end-century). Average daily PWC values were aggregated for the entire year, the growing season, and the warmest 90-day period of the year. Under recent past climate conditions, the growing season PWC was below 0.86 (86% of full work capacity) on half the current global cropland. With end-century/SSP5-8.5 thermal conditions this value was reduced to 0.7, with most affected crop-growing regions in Southeast and South Asia, West and Central Africa, and northern South America. Average growing season PWC could falls below 0.4 in some important food production regions such as the Indo-Gangetic plains in Pakistan and India. End-century PWC reductions were substantially greater than mid-century reductions. This paper assesses two potential adaptions-reducing direct solar radiation impacts with shade or working at night and reducing the need for hard physical labor with increased mechanization. Removing the effect of direct solar radiation impacts improved PWC values by 0.05 to 0.10 in the hottest periods and regions. Adding mechanization to increase horsepower (HP) per hectare to levels similar to those in some higher income countries would require a 22% increase in global HP availability with Sub-Saharan Africa needing the most. There may be scope for shifting to less labor-intensive crops or those with labor peaks in cooler periods or shift work to early morning., (© 2024 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

In this paper, we argue for the inclusion of archaeology in discussions about how humans have contributed to and dealt with climate change, especially in the long term. We suggest Niche Construction Theory as a suitable framework to that end. In order to take into account both human and environmental variability, we also advocate for a situated perspective that includes the Global South as a source of knowledge production, and the Neotropics as a relevant case study to consider. To illustrate this, we review the mid-Holocene Hypsithermal period in the southern Puna and continental Patagonia, both in southern South America, by assessing the challenges posed by this climate period and the archaeological signatures of the time from a Niche Construction Theory perspective. Finally, we emphasize the importance of these considerations for policymaking. This article is part of the theme issue 'Climate change adaptation needs a science of culture'.

In a jungle environment where jaguars are considered human, systems thinking has evolved in unexpected ways. Although systems thinking is commonly seen as a product of the Western world, other cultures have developed their own versions with unique characteristics. In this article, we explore Amazonian systems thinking, which has similarities to modern Western systems thinking, as well as differences that may inspire the evolution of systems approaches worldwide. We will discuss the contributions of Amazonian systems thinking particularly to find answers to the planet's ecological and sustainability problems, such as climate change and mass extinction of species, among others. We will present the systems thinking that emerged in some Amazonian communities, how it relates to mainstream Western systems thinking, and focus on some unique aspects of Amazonian systems thinking. This paper is based on the ethnographic work of Gerardo Reichel‐Dolmatoff and other anthropologists who have studied Amazonian communities for decades. [ABSTRACT FROM AUTHOR]

This paper assesses the state of knowledge of climate change and tourism in South and Central America, with a special focus on the characteristics of the tourism sector, the particularities of climate risks of the region and the sectoral GHG contribution. We conducted a scientific literature review (by region and by country) in Spanish, Portuguese and English using publications in the Scopus and Google databases to the end of 2021. In parallel, we performed a search for institutional publications, programs, and strategies on climate change and tourism in South and Central American countries. This analysis identified the main challenges and potentialities between tourism and climate change in the region. Among the main findings is the limited number of studies and lack of primary data to inform policy formulation and tourism planning. Likewise, national, and regional public policies specific to tourism are scarce, while multisectoral climate plans have only recently been developed and, consequently, are difficult to evaluate. [ABSTRACT FROM AUTHOR]

The Sixth Assessment Report (AR6) of the Intergovernmental Panel on Climate Change represents the state of knowledge of anthropogenic disruption to the climate system, its diverse ecosystem and societal impacts, and the imperative for and challenges of mitigation and adaptation responses. It is foundational for global climate policymaking. This paper examines the place of tourism in AR6 and reviews its key findings for tourism's future. Overall, tourism related content declined relative to previous assessments. While notable improvements in content occurred for Africa, visible knowledge gaps remain in the tourism growth regions of South America, Middle East, and South Asia. There remains limited discussion of many impacts, and very limited understanding of integrated impacts and the effectiveness of adaptation strategies at the destination scale. The contribution of tourism to global emissions was omitted, however tourism was discussed in the context of luxury emissions and just transitions. Tourism is repeatedly identified in solution space discussions, particularly for ecosystem protection, but without consideration of the future of tourism in a rapidly decarbonizing and climate disrupted economy. With only 21% of published climate change and tourism literature in the AR6 review period cited, tourism academics should elevate tourism content and engagement in future assessments. [ABSTRACT FROM AUTHOR]

We attempt to summarize the carbon budget of South America and relate it to its dominant controls: population and economic growth, changes in land use practices and a changing atmospheric environment and climate. Flux estimation methods which we consider sufficiently reliable are fossil fuel emission inventories, biometric analysis of old-growth rainforests, estimation of carbon release associated with deforestation based on remote sensing and inventories, and finally inventories of agricultural exports. Other routes to estimating land-atmosphere CO2 fluxes include atmospheric transport inverse modelling and vegetation model predictions but are hampered by the data paucity and the need for improved parameterisation. The available data we analyze suggest that South America was a net source to the atmosphere during the 1980s (~0.3-0.4 PgCyr-1) and close to neutral (~0.1 PgCyr-1) in the 1990s with carbon uptake in old-growth forests nearly compensating carbon losses due to fossil fuel burning and deforestation. Annual mean precipitation over tropical South America measured by Amazon River discharge has a long-term upward trend, although over the last decade, dry seasons have tended to be drier and longer (and thus wet seasons wetter), with the years 2005 and 2010 experiencing strong droughts. It is currently unclear what the effect of these climate changes on the old-growth forest carbon sink will be but first measurements suggest it may be weakened. Based on scaling of forest census data the net carbon balance of South America seems to have been an increased source roughly over the 2005-2010 period (a total of ~1 PgC of dead tree biomass released over several years) due to forest drought response. Finally, economic development of the tropical forest regions of the continent is advancing steadily with exports of agricultural products being an important driver and witnessing a strong upturn over the last decade. [ABSTRACT FROM AUTHOR]

Purpose: Offshoring of pulpwood production outside Europe is more and more common, which increases transport distances and also changes production technologies, raw material supply and energy production profiles. In this paper, we aim to compare the life cycle greenhouse gas emissions of pulp production from Finnish boreal hardwood and from South American eucalyptus. Special emphasis was placed on analysing the contribution of transport to overall climate impacts. Materials and methods: A life cycle assessment (LCA) was used as the system modelling tool. The impact assessment was limited to climate change. Finnish and South American industrial data were combined with data from LCA databases in the life cycle inventory (LCI). Results and discussion: Based on the results, offshoring of pulp production would decrease the global greenhouse gas emissions of pulp production itself. However, transport to Europe outweighs the benefit even if transported by energy efficient ships. In this case study, transportation accounted for 27% of the life cycle greenhouse gas emissions of South American pulp shipped to Europe. Conclusions: Outsourcing of biomass production offers opportunities for emission reductions. Such a conclusion may be valid if the distances between biomass production and upgrading processes were relatively short. However, this study reveals that the offshoring of biomass production contributes to a significant growth of transport emissions. The trend of offshoring provides challenges for the implementation of emission trading since the responsibility of countries to transoceanic transport is still unclear. [ABSTRACT FROM AUTHOR]

Mercury accumulation in lake sediments has been extensively studied with regard to anthropogenic signals, but natural processes controlling mercury accumulation in the past and the influence of environmental and climatic changes are still poorly understood. In this study we present a 17 300 years old record of mercury accumulation in lake sediments in combination with a multi-proxy investigation of climatic and environmental changes in Southernmost Patagonia (53° S). Mercury accumulation in the remote pristine lake has been highly variable (up to a factor of 16), clearly exceeding the anthropogenic forcing of atmospheric mercury fluxes (factor of 3-5). Statistical data evaluation based on Principle Component Analysis reveals that the dominant driver of variations in mercury accumulation along with other organically bound elements (e.g. copper and yttrium) has been leaching of soluble organic complexes from catchment soils. This indicates that changes in precipitation rates and soils leaching are the most important climatic driver for short term variations in mercury in the lake's sediments. In the long term, however, mercury accumulation rates remain relatively constant (29 µgm-2 yr-1). This reflects that mercury accumulation in the catchment soils through atmospheric deposition and bedrock weathering has been fairly constant, too. As carbon storage in the soils and transport into the lake have increased, Hg/C ratios in the soil OM decreased. Fluxes of Hg into the lake are therefore mainly determined by the amount of OM leached into the lake and its Hg/C ratio. [ABSTRACT FROM AUTHOR]

As a global industry, sport makes potentially significant contributions to climate change through both carbon emissions and influence over sustainability practices. Yet, evidence regarding impacts is uneven and spread across many disciplines. This paper investigates the impacts of sport emissions on climate and identifies knowledge gaps. We undertook a systematic and iterative meta‐analysis of relevant literature (1992–2022) on organized and individual sports. Using a defined search protocol, 116 sources were identified that map to four sport‐related themes: (1) carbon emissions and their measurement; (2) emissions control and decarbonization; (3) carbon sinks and offsets; and (4) behavior change. We find that mega sport events, elite sport, soccer, skiing, and golf have received most attention, whereas grass‐roots and women's sport, activity in Africa and South America, cricket, tennis, and volleyball are understudied. Other knowledge gaps include carbon accounting tools and indicators for smaller sports clubs and active participants; cobenefits and tradeoffs between mitigation‐adaptation efforts in sport, such as around logistics, venues, sports equipment, and facilities; geopolitical influence; and scope for climate change litigation against hosts and/or sponsors of carbon‐intensive events. Among these, researchers should target cobenefits given their scope to deliver wins for both climate mitigation and risk management of sport. [ABSTRACT FROM AUTHOR]

The rise in the Earth's global average surface temperature and the increase of extreme weather events have been the focus of scientific discussion in the last decades. Extreme heat combined with other environmental extremes, like high concentrations of air pollution, may induce health problems—especially in socioeconomically vulnerable populations. Spring in South America requires particular attention due to its association with hot, dry weather and air pollution in most parts of the continent. This paper intends to better comprehend the behaviour of heatwaves during the austral winter–spring transition. We propose identifying the spatial coverage, frequency and intensity of heatwaves in homogeneous areas of maximum air temperature near the surface (Tmax). We employed cluster analyses during the period between July and October for 41 years (1979–2019) through the ERA5 reanalysis. Homogeneous Tmax areas in South America were defined by cluster analyses that indicated three homogeneous Tmax regions, as follows: a larger area of the continent including the tropical region (Area 1), eastern and southeastern South America (Area 2) and southernmost and steep areas in the Andes (Area 3). The heatwave events identified via ERA5 reanalysis were classified according to their intensity (intense, moderate and weak events). Spatial frequency and trend analyses were also performed regarding the intensity and persistence of heatwave episodes. These methods allowed the identification of the behavioural aspect of heatwaves spanning the last four decades. The Mann–Kendall statistical test (MK) was applied in order to analyse the heatwave trend with a statistical significance level of 5%. A total of 191 heatwave episodes were identified. Of this total, 47.12, 35.60 and 17.28% of episodes occurred in Areas 2, 3 and 1, respectively. The hotter area extending from northeast to southwest in central South America stood out by its largest frequencies of intense heatwave episodes. Across the continent there was a significant increase in the intensity and persistence of heatwaves over the period of 1979 through to 2019. [ABSTRACT FROM AUTHOR]

Global warming is causing an intensification of extreme climate events with significant changes in frequency, duration, and intensity over many regions. Understanding the current and future influence of this warming in northeastern Brazil (NEB) is important due to the region's greater vulnerability to natural disasters, as historical records show. In this paper, characteristics of climate change projections (precipitation and air temperature) over NEB are analyzed using 15 models of Coupled Model Intercomparison Project Phase 6 (CMIP6) under four Shared Socioeconomic Pathways (SSPs: SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5) scenarios. By using the Taylor diagram, we observed that the HadGEM3-GC31-MM model simulates the seasonal behavior of climate variables more efficiently. Projections for NEB indicate an irreversible increase in average air temperature of at least 1 °C throughout the 21st century, with a reduction of up to 30% in annual rainfall, as present in scenarios of regional rivalry (SSP3-7.0) and high emissions (SSP5-8.5). This means that a higher concentration of greenhouse gases (GHG) will increase air temperature, evaporation, and evapotranspiration, reducing rainfall and increasing drought events. The results obtained in this work are essential for the elaboration of effective strategies for adapting to and mitigating climate change for the NEB. [ABSTRACT FROM AUTHOR]

Pasturelands are globally extensive, sensitive to climate, and support livestock production systems that provide an essential source of food in many parts of the world. In this paper, we integrate information from remote sensing, global climate, and land use databases to improve understanding of the resilience and resistance of this ecologically vulnerable and societally critical land use. To characterize the effect of climate on pastureland productivity at global scale, we analyze the relationship between satellite‐derived enhanced vegetation index data from MODIS and gridded precipitation data from CHIRPS at 3‐ and 6‐month time lags. To account for the effects of different production systems, we stratify our analysis by agroecological zones and by rangeland versus mixed crop‐livestock systems. Results show that 14.5% of global pasturelands experienced statistically significant greening or browning trends over the 15‐year study period, with the majority of these locations showing greening. In arid ecosystems, precipitation and lagged vegetation index anomalies explain up to 69% of variation in vegetation productivity in both crop‐livestock and rangeland‐based production systems. Livestock production systems in Australia are least resistant to contemporaneous and short‐term precipitation anomalies, while arid livestock production systems in Latin America are least resilient to short‐term vegetation greenness anomalies. Because many arid regions of the world are projected to experience decreased total precipitation and increased precipitation variability in the coming decades, improved understanding regarding the sensitivity of pasturelands to the joint effects of climate change and livestock production systems is required to support sustainable land management in global pasturelands. Plain Language Summary: Pastures, which provide food for livestock, are the most extensive land use on the planet, and their productivity depends on the timing and amount of rainfall they receive. In this paper, we use data on vegetation productivity, rainfall, and land use in order to determine the ability of pastures to remain unaffected by a disturbance and the time required for pastures to recover following a disturbance. To determine the effects of rainfall on pastures, we analyze the relationship between productivity and rainfall at 3‐ and 6‐month time intervals. We also take into account pasture management and whether pastures are located in dry or humid areas of the world. In dry regions, rain from the current season, rain from the last two seasons, and vegetation productivity from the previous growing season explain nearly 70% of current season vegetation productivity. Pastures in Australia are least capable of withstanding rainfall deficits, while pastures in Latin America recover more slowly after drought compared to other regions. Dry regions of the world are predicted to receive less rain less regularly in the coming decades, so improved understanding of the sensitivity of pastures to expected changes in rainfall will help support sustainable management of global pastures. Key Points: In Australia, pasturelands have both low resistance and low resilience relative to other regions across the worldSouthern South America has the lowest resilience globally, which is indicative of slow vegetation recovery after a disturbanceA total of 14.5% of global pasturelands experienced greening or browning trends, with the majority of these locations showing greening [ABSTRACT FROM AUTHOR]

The article offers the authors' insight on the paper "Are bird populations in tropical and subtropical forests of South America affected by climate change?," by M. Nores that was published in a 2009 issue of "Climatic Change." The authors say that the bird data underestimates the current number of birds in South American forests. They add that the methods used are unacceptable in the field of modern ornithology and the paper lacks insight on the possible climate change effects on birds in the forests.

Cocoa is a plant with origins in northwestern South America with high relevance in the global economy. Evidence indicates that cocoa is sensitive to a dry climate, under which crop production is reduced. Projections for future climate change scenarios suggest a warmer and drier climate in the Amazon basin. In this paper, we quantify the potential effects in cocoa production due to its edaphoclimatic suitability changes to the Brazilian Amazon biome and account for regional differences in planning occupation territories. We modeled the suitability of cocoa's geographical distribution using an ensemble of 10 correlative models that were run in the "biomod2" library and projected to two future climate scenarios (RCPs 4.5 and 8.5) by 2050. Combining information on climate and soil suitability and installed infrastructure in the macro-regions of the Brazilian Amazon. We defined a zoning system to indicate how cocoa production may respond to climate change according to the current and future suitability model. Our results suggest that a reduction in precipitation and an increase in temperature may promote a reduction in the suitability of cocoa production in the Brazilian Amazon biome. In addition of the areas suitable for cocoa plantation, we found a 37.05% and 73.15% decrease in the areas suitable for intensification and expansion zones under RCP 4.5 and 8.5, respectively, compared with the current scenario. We conclude that there may be a need to expand land to cocoa production in the future, or else it will be necessary to plant a cocoa variety resistant to new climatic conditions. Besides, we recommend procedures to combat illegal deforestation to prevent the most critical climate change scenarios from occurring. [ABSTRACT FROM AUTHOR]

This paper presents a novel methodology in which an individual's optimization decisions are statistically decomposed into choices of systems, system-specific outcomes, and the overall outcome in an integrative framework. The methodology is applied to individuals' decisions on natural resource enterprises given climatic changes. This paper finds that when the Goddard Institute scenario comes to pass by the middle of this century, adoption of a crops-only enterprise will fall, so will adoption of a crops-forests enterprise. Instead, people will increase adoption of a livestock-only as well as a crops-livestock-forests enterprise. The impacts of climate change on the six enterprises are varied, which are calculated from the estimated models by altering climate variables. The crops-only enterprise will lose the value of land by 8.3 %. However, the livestock-only enterprise will gain by 8.9 %. The crops-livestock-forests enterprise also will gain largely by 7.8 %. The impacts on the other enterprises are muted, e.g., 1 % gain for the crops-livestock enterprise. The total damage under the scenario is expected to be a loss of 1.9 % of land value. Under a severer UK Met Office scenario, the damage is predicted to increase to 6.2 %. [ABSTRACT FROM AUTHOR]

This paper evaluates behavioral adaptation models to climate change using South American agricultural data. This paper finds that the Ricardian model with spatial effects leads to 20 % loss of land value under the UK Hadley center (UKMO hereafter) model and 11 % loss under the milder US Goddard Institute (GISS hereafter) model by the middle of the century. The micro portfolio adaptation model (G-MAP hereafter), on the other hand, results in a much smaller damage estimate: 1 % loss of land value under the GISS model and 3.4 % loss under the UKMO model. Even with the G-MAP model, however, the land value of the crops-only system falls sharply by as much as 9.5 % under the GISS scenario. In contrast to the Ricardian model, the G-MAP model can explicitly explain the decisions to choose one of the agricultural systems as well as the conditional land value function for each system of agriculture. Under the GISS model, the choice of a crops-only farm declines by 3.3 % which is offset by an increase in the mixed system by 2.1 % and an increase in the livestock-only system by 1.2 %. Although the land value of the crops-only system falls by 9.5 %, the land value of the mixed system falls only by 3.5 % while that of the livestock-only system increases by a large percentage. This paper finds that the differences in the impact estimates between the two models result from the treatment of sunk cost. The result from the Ricardian model would deviate from that from the G-MAP model if sunk cost is significantly large. [ABSTRACT FROM AUTHOR]

Peatlands are carbon-rich ecosystems that cover 185-423 million hectares (Mha) of the earth's surface. The majority of the world's peatlands are in temperate and boreal zones, whereas tropical ones cover only a total area of 90-170 Mha. However, there are still considerable uncertainties in C stock estimates as well as a lack of information about depth, bulk density and carbon accumulation rates. The incomplete data are notable especially in tropical peatlands located in South America, which are estimated to have the largest area of peatlands in the tropical zone. This paper displays the current state of knowledge surrounding tropical peatlands and their biophysical characteristics, distribution and carbon stock, role in the global climate, the impacts of direct human disturbances on carbon accumulation rates and greenhouse gas (GHG) emissions. Based on the new peat extension and depth data, we estimate that tropical peatlands store 152-288 Gt C, or about half of the global peatland emitted carbon. We discuss the knowledge gaps in research on distribution, depth, C stock and fluxes in these ecosystems which play an important role in the global carbon cycle and risk releasing large quantities of GHGs into the atmosphere (CO 2 and CH 4 ) when subjected to anthropogenic interferences (e.g., drainage and deforestation). Recent studies show that although climate change has an impact on the carbon fluxes of these ecosystems, the direct anthropogenic disturbance may play a greater role. The future of these systems as carbon sinks will depend on advancing current scientific knowledge and incorporating local understanding to support policies geared toward managing and conserving peatlands in vulnerable regions, such as the Amazon where recent records show increased forest fires and deforestation., (© 2020 John Wiley & Sons Ltd.)

Climate change is causing extensive alterations to ecosystems globally, with some more vulnerable than others. Alpine ecosystems, characterised by low-temperatures and cryophilic vegetation, provide ecosystems services for billions of people but are considered among the most susceptible to climate change. Therefore, it is timely to review research on climate change on alpine vegetation including assessing trends, topics, themes and gaps. Using a multicomponent bibliometric approach, we extracted bibliometric metadata from 3143 publications identified by searching titles, keywords and abstracts for research on 'climate change' and 'alpine vegetation' from Scopus and Web of Science. While primarily focusing on 'alpine vegetation', some literature that also assessed vegetation below the treeline was captured. There has been an exponential increase in research over 50 years, greater engagement and diversification in who does research, and where it is published and conducted, with increasing focus beyond Europe, particularly in China. Content analysis of titles, keywords and abstracts revealed that most of the research has focused on alpine grasslands but there have been relatively few publications that examine specialist vegetation communities such as snowbeds, subnival vegetation and fellfields. Important themes emerged from analysis of keywords, including treelines and vegetation dynamics, biodiversity, the Tibetan Plateau as well as grasslands and meadows. Traditional ecological monitoring techniques were important early on, but remote sensing has become the primary method for assessment. A key book on alpine plants, the IPCC reports and a few papers in leading journals underpin much of the research. Overall, research on this topic is increasing, with new methods and directions but thematic and geographical gaps remain particularly for research on extreme climatic events, and research in South America, in part due to limited capacity for research on these rare but valuable ecosystems., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Climate change impacts are already happening through the world, and it is now clear that there is the need for an adaptive response from global institutions down to the local level. Reducing vulnerability to cope with climate variability might be more challenging in tropical countries than in North America or Europe. The ten papers of this special issue were presented during the Adaptclim conference that was held by the Sinergia Project, the CLARIS LPB project, and the GeoData Institute in Asunción, Paraguay, in 2010. All papers, except one regarding the Brahmaputra Basin in South Asia, present studies from South America. These studies are first contextualized geographically and then are related one to another by a simplified vulnerability concept linking climate stress to sensitivity and adaptive capacity of natural and human systems. One half of the papers focus on actual or future climate change and the present-day causes of the vulnerability of natural and agrosystems. Droughts are and will be the main source of stress for agriculture in South America. Increasing fragmentation of forest of the center of this continent is aggravating their vulnerability to dry spells. Another half of the studies of this special issue deal with the adaptive capacity human populations to system perturbations produced or enhanced by climate change. The studies point out inclusion of traditional knowledge and involvement of local actors in their own vulnerability assessment to increase adaptive capacity. These elements of climate justice, giving voice to those less responsible for carbon emissions but bearing their most severe consequences, allow the particular needs of a community to be considered and can direct adaptation policy toward preserving or rebuilding their specific capabilities under threat from climate change. The special issue also made clear that a basin analysis of the climate change problem could provide information, results, and methods more readily of use for the local population and decision makers. [ABSTRACT FROM AUTHOR]

The Choco low-level jet is among the main regional circulation mechanisms related to the advection of water vapor from the eastern Pacific to northwestern South America. Variations in the intensity of position of the jet core are identified as determinant for regional moisture transport and associated rainfall. This paper analyzes the annual cycle of intensity and latitudinal location of this jet according to different reanalysis and observational datasets. Moreover, we compare possible changes in the Choco jet occurred during past climates, like the little ice age (LIA), with those associated with future scenarios of greenhouse gas concentrations (RCP8.5), using simulations from the Paleoclimate Modelling Intercomparison Project Phase 3 (PMIP3) and the Coupled Model Intercomparison Project Phase 5 (CMIP5). Our results suggest that according to reanalysis/observational data, as well as the CMIP5 models with the best representation of the Choco jet in present climate, there is a positive correlation between the jet intensity and its latitudinal location, and such relationship is associated with the sea level pressure (SLP) difference between the eastern tropical Pacific and the northwestern South American landmass. Hence, stronger (weaker) SLP differences favor a stronger (weaker) intensity and a northward (southward) location of the Choco jet. PMIP3 simulations suggest a stronger and northward Choco jet during LIA due to a stronger SLP difference in comparison to present climate. However, under the RCP8.5 scenario, there is not robust agreement among CMIP5 models although the best models suggest a southward jet at the end of the 21st century. This suggests that the mechanisms influencing the Choco jet may play different roles during past natural climate changes with respect to anthropogenically-forced climate changes. [ABSTRACT FROM AUTHOR]

This paper describes changes of near-surface air temperature in southern South America from the Last Glacial Maximum (~ 21,000 years before present) to the end of the twenty-first century based on PMIP3-CMIP5 model simulations. The study shows modeled time evolution of temperature highlighting how different the projected future warming will be with respect to paleoclimatic changes documented in the region. In this context, model simulations suggest that the projected twenty-first century warming will be markedly higher than the change of temperature registered between the mid-Holocene (~ 6000 years before present) and the present. Even more, the regional warming projected by the following 60–80 years might be almost similar to or even higher than the pronounced increment of temperature developed between the Last Glacial Maximum and the present. This past/future comparison provides a new picture of the unusual warming expected for the following decades in southern South America in the context of climate changes developed through the last ca. 21,000 years. [ABSTRACT FROM AUTHOR]

Although econometric models have been widely used to measure the impact of climate change on agriculture, there exist differences among the modelers on which specification should be preferred. To help explain the discrepancies, this paper assesses four different econometric models, i.e. OLS, panel, and two spatial models using a South American agricultural household data. The relationship among the econometric specifications is examined in terms of the freedom given to a spatial autoregressive parameter. In spatial models, the spatial parameter is free within the model, but is fixed a priori in the aspatial models. Empirical results show a high correlation of the land values across South America. Spatial models result in somewhat lower climate change impact estimates than those from the aspatial models. [ABSTRACT FROM AUTHOR]

The Andes Cordillera plays a role in driving moisture and heat from tropical onto subtropical South America. It forces the development of a lee-side trough that covers most of western Argentina and a low-level jet that maximizes over Paraguay, eastern Bolivia and northern Argentina and is tightly linked to precipitation variability over much of central and southeastern South America. Its steep slopes and the large zonal gradients in topography between the Equator and 40°S are misrepresented in climate simulations using Global Climate Models (GCM) with resolutions coarser than about 100 km, since they naturally have a poor representation of the Andes and related circulation features. This paper analyses the impact of varying artificially the altitude of the Andes Cordillera in a GCM as well as increasing the horizontal resolution to study how these variations determine moisture fluxes and precipitation over selected regions of South America. Results show that the height of the Andes is crucial in shaping moisture fluxes pathways onto subtropical South America all year long. In particular, the low-level jet is only simulated when the Andes heights are doubled. At the same time, the relationship between the Andes shape and the location of the Bolivian High in summer is also discussed. In terms of precipitation, the lowest bias in the simulations is achieved when the horizontal resolution is increased, while in particular near the Andes foothills the simulated annual rainfall is largely determined by the Mountains shape. [ABSTRACT FROM AUTHOR]

On a hemispheric scale, it is now well established that stratospheric ozone depletion has been the principal driver of externally forced atmospheric circulation changes south of the Equator in the last decades of the 20th Century. The impact of ozone depletion has been felt over the entire hemisphere, as reflected in the poleward drift of the midlatitude jet, the southward expansion of the summertime Hadley cell and accompanying precipitation trends deep into the subtropics. On a regional scale, however, surface impacts directly attributable to ozone depletion have yet to be identified. In this paper we focus on South Eastern South America (SESA), a region that has exhibited one of the largest wetting trends during the 20th Century. We study the impact of ozone depletion on SESA precipitation using output from 6 different climate models, spanning a wide range of complexity. In all cases we contrast pairs of model integrations with and without ozone depletion, but with all other forcings identically specified. This allows for unambiguous attribution of the computed precipitation trends. All 6 climate models consistently reveal that stratospheric ozone depletion results in a significant wetting of SESA over the period 1960-1999. Taken as a whole, these model results strongly suggest that the impact of ozone depletion on SESA precipitation has been as large as, and quite possibly larger than, the one caused by increasing greenhouse gases over the same period. [ABSTRACT FROM AUTHOR]

What are the lessons from development practice that adaptation interventions can use to engage vulnerable people? To answer this question, the paper reviews field data on perceptions of environmental and climatic change in a Peruvian mountain community and discusses the possibilities and limitations of using local climate voices to prepare for climate change adaptation. The data comprise two complementary household surveys. The first survey provides information on the community’s socio-economic situation, whilst the second survey documents the villagers’ climate perception. The data reveal a paradox in the way the community understands global climate change. The villagers who live on the margin of the global world and belong to the poorest economic strata in Peru are deeply concerned about global climate change that is impacting their environment. Yet when locating the cause of climate change they point to their own community rather the industrialized world and suggest mitigation actions rather than adaptation initiatives as answer to the problems it entails. The paper suggests that adaptation initiatives must understand this paradox within the larger socio-economic and discursive context that shapes the villagers’ agency and climate perceptions. It proposes an informed participation approach that listens to the local voices but that also informs them about the global dimensions of climate change and engages them in a critical dialogue about the importance of sustainable development and the possibilities of taking advantage of the new opportunities that the changing environment offers. [ABSTRACT FROM AUTHOR]

Global warming during the Last Glacial Termination was interrupted by millennial-scale cool intervals such as the Younger Dryas and the Antarctic Cold Reversal (ACR). Although these events are well characterized at high latitudes, their impacts at low latitudes are less well known. We present high-resolution temperature and hydroclimate records from the tropical Andes spanning the past ~16,800 y using organic geochemical proxies applied to a sediment core from Laguna Llaviucu, Ecuador. Our hydroclimate record aligns with records from the western Amazon and eastern and central Andes and indicates a dominant long-term influence of changing austral summer insolation on the intensity of the South American Summer Monsoon. Our temperature record indicates a ~4 °C warming during the glacial termination, stable temperatures in the early to mid-Holocene, and slight, gradual warming since ~6,000 y ago. Importantly, we observe a ~1.5 °C cold reversal coincident with the ACR. These data document a temperature change pattern during the deglaciation in the tropical Andes that resembles temperatures at high southern latitudes, which are thought to be controlled by radiative forcing from atmospheric greenhouse gases and changes in ocean heat transport by the Atlantic meridional overturning circulation. [ABSTRACT FROM AUTHOR]

The vast diversity of present vegetation and environments that occur throughout South America (12°N to 56°S) is the result of diverse processes that have been operating and interacting at different spatial and temporal scales. Global factors, such as the concentration of CO2 in the atmosphere, may have been significant for high altitude vegetation during times of lower abundance, while lower sea levels of glacial stages potentially opened areas of continental shelf for colonisation during a substantial portion of the Quaternary. Latitudinal variation in orbital forcing has operated on a regional scale. The pace of climate change in the tropics is dominated by precessional oscillations of c. 20 kyr, while the high latitudes of the south are dominated by obliquity oscillations of c. 40 kyr. In particular, seasonal insolation changes forced by precessional oscillations must have had important consequences for the distribution limits of species, with potentially different effects depending on the latitude. The availability of taxa, altitude and human impact, among other events, have locally influenced the environments. Disentangling the different forcing factors of environmental change that operate on different timescales, and understanding the underlying mechanisms leads to considerable challenges for palaeoecologists. The papers in this Special Issue present a selection of palaeoecological studies throughout South America on vegetation changes and other aspects of the environment, providing a window on the possible complexity of the nature of transitions and timings that are potentially available. [ABSTRACT FROM AUTHOR]

General circulation models (GCMs) forced under different greenhouse gases emission and socioeconomic scenarios are currently the most extended tool throughout the scientific community that is used to infer the future climate on Earth. However, these models still have problems in capturing several aspects of regional climate variability in many parts of the globe. In this paper, the hydrological cycle of the La Plata Basin is simulated using the variable infiltration capacity (VIC) distributed hydrology model and forced with atmospheric data from different GCMs to determine to what extent errors in temperature and precipitation fields impact the hydrology of the basin. The skill assessment is performed in terms of simulated runoff at different closing points. Simulated hydrographs show that all of the GCMs present deficiencies in simulating the regional climatology of southern South America, and this leads to a very poor representation of the hydrological cycle of the main rivers across the basin. Two unbiasing schemes are then proposed as a means of correcting the GCM outputs before forcing the hydrology model, and comparisons between biased and unbiased simulations are also performed. Results indicate that both schemes, though methodologically different, reduce the water cycle simulation bias. Finally, VIC is forced with bias-corrected data from the GCMs for future decades (2030 and 2070) under different socioeconomic scenarios [e.g., the Intergovernmental Panel on Climate Change's (IPCC) Special Report on Emissions Scenarios (SRES) scenarios A1B, A2, and B1] to determine the potential changes in streamflow due to climate change for the rest of the present century. [ABSTRACT FROM AUTHOR]

This paper develops a microeconometric analysis of adapting portfolios in response to climate change using information on South American farmers' adoption of agricultural systems taken from approximately 2,000 household surveys. The results show that farmers in a hotter climate prefer a mixed system over specialized systems either in crops or livestock. Under a hot and dry scenario, the land values of all three systems would fall, but the damage would be much smaller in the mixed system (−10%) than for the farms specializing in crops (−20%). Farmers are predicted to lose 8% of their land's value under the Canadian Climatic Center (CCC) scenario, but only 2% under the Parallel Climate Model (PCM). Losses would increase to 18% if they do not adapt. [ABSTRACT FROM PUBLISHER]

An important goal of the Climate Variability and Predictability (CLIVAR) research on the American monsoon systems is to determine the sources and limits of predictability of warm season precipitation, with emphasis on weekly to interannual time scales. This paper reviews recent progress in the understanding of the American monsoon systems and identifies some of the future challenges that remain to improve warm season climate prediction. Much of the recent progress is derived from complementary international programs in North and South America, namely, the North American Monsoon Experiment (NAME) and the Monsoon Experiment South America (MESA), with the following common objectives: 1) to understand the key components of the American monsoon systems and their variability, 2) to determine the role of these systems in the global water cycle, 3) to improve observational datasets, and 4) to improve simulation and monthly-to-seasonal prediction of the monsoons and regional water resources. Among the recent observational advances highlighted in this paper are new insights into moisture transport processes, description of the structure and variability of the South American low-level jet, and resolution of the diurnal cycle of precipitation in the core monsoon regions. NAME and MESA are also driving major efforts in model development and hydrologic applications. Incorporated into the postfield phases of these projects are assessments of atmosphere–land surface interactions and model-based climate predictability experiments. As CLIVAR research on American monsoon systems evolves, a unified view of the climatic processes modulating continental warm season precipitation is beginning to emerge. [ABSTRACT FROM AUTHOR]

This paper presents estimates for potato demand, supply and trade in South America to the year 2030 according to three scenarios: baseline, high demand and limited supply. The results highlight the importance of Brazil with its massive population and low per capita consumption of potato as a key driver of regional outcomes. According to the baseline and high demand scenarios, improved productivity in Andean countries such as Ecuador and Colombia will influence output and consumption increases in those locations as well. The potential adverse effects of the advent of climate change on the potato sector in more vulnerable growing areas in the region will result in much more modest increases in output in those locations according to the low supply scenario. While domestic potato marketing will continue to expand, foreign trade in potatoes remains small in absolute terms and as a percentage of national and sub-regional output. The findings call attention to opportunities for agribusiness initiatives in input markets as well as for both fresh and processed potato products for human consumption in the decades ahead. [ABSTRACT FROM AUTHOR]

Water erosion, a notorious major threat to food security and ecosystem sustainability, is strongly conditioned by spatial and temporal scale effects. This paper systematically reviews the scale issues in runoff and sediment delivery (SIRSD) as a research field by integrating the traditional review approach and bibliometric analysis. This review summarises SIRSD's roots and the scale effect on runoff and sediment delivery. Then, we provide quantitative insights into the SIRSD domain's development history, thematic structure, geographic distribution, international cooperation, and methodologies. Findings show that: i) SIRSD arises from the gap between the non-linearity of runoff and sediment delivery across scales and our ability to measure it. Point-based and short-term measurements cannot capture the non-linearities from the spatio-temporal heterogeneities and cross-scale interactions of factors or processes. ii) Previous literature provides evidence that the spatial scaling of specific runoff (r), soil erosion (SE), sediment yield (SSY), or sediment delivery ratio (SDR) with drainage area (A) or slope length (L) exhibits contrasting patterns due to distinct mechanisms. Infiltration-excess and saturation-excess processes account for inverse and positive r - A relations, respectively. Interrill-erosion and rill-erosion cause inverse and positive SE-L relations. Hillslope-erosion and channel/bank-erosion explain inverse and positive SSY-A relations. Downstream increasing deposition and additional sediment inputs drive inverse and positive SDR-A relations. These scaling relationships can be nonlinear or complex due to spatial heterogeneities in land use, vegetation, topography, climate, lithology, and soil characteristics. Hence, applying an empirical scaling equation developed from the region with distinct environmental contexts is not recommended. Furthermore, the existing scaling patterns or equations may require updating given global climate and land use change. iii) SIRSD is a complex and multidisciplinary issue investigated by scientists from 93 countries since 1928. International research has substantially facilitated the understanding of SIRSD; still, more collaboration should focus on less-developed countries with high soil and water loss risks and urgent conservation needs, such as those in Africa and South America under cropland expansion. iv) Scale mismatch and scale break have discredited large-scale erosion and sediment assessments. Incorporating gully and bank erosion into modelling, extending the scale range of the L factor, and expanding the sediment scaling scope from watershed to slope may make a difference. Therefore, more research with nested design incorporating multiple scales is necessary for cross-scale analysis and scalable modelling. Addressing global climate change requires improving real-time urban flood forecasting and integrating downscaled climate models with hydrology, erosion, and sediment transport models. • A bibliometric review of the global SIRSD research for the first time. • SIRSD is rooted in the gap between natural nonlinearity and our measuring ability. • Scaling of specific runoff, erosion, sediment yield, and SDR has diverse patterns. • Scale mismatch and scale break discredit large-scale modelling and assessments. [ABSTRACT FROM AUTHOR]

Background: climate change is a reality, and more and more people are becoming aware of this global problem, which has generated anxiety in some populations. To validate a short survey to assess eco-anxiety in adults in South America. Methods: It is an instrumental study, and the validation was based on a previous survey, which had six questions and was generated by 217 respondents in the USA in 2021. These questions were subjected to a validation process with expert judgment, pilot and application, and then statistics were obtained. It was validated with 1907 people in six countries in South America, where the mean, standard deviation, skewness and kurtosis were adequate. Results: The initial confirmatory factorial model obtained unsatisfactory goodness-of-fit indices, so the indices were modified through a re-specification, where two items were eliminated, after which adequate values were obtained (χ2 = 22.34, df = 2, p = 0.00; RMR = 0.020; GFI = 0.990; CFI = 0.990; TLI = 0.990; and RMSEA = 0.070). Finally, the overall Cronbach's α was calculated to be 0.88 (95% CI = 0.86–0.89). Conclusions: The test was validated in a large South American population and found that only four questions can efficiently measure anxiety about the effects of climate change. The instrument can be used with other tests to screen different age groups, ethnicities and realities. [ABSTRACT FROM AUTHOR]

Paleoclimatological field reconstructions are valuable for understanding hydroclimatic variability. While being similarly impactful on societies as temperature variability, hydroclimatic variability has still remained less in focus. However, reconstructing globally complete fields of climate variables lacks adequate proxy data from tropical regions like South America, limiting our understanding of past hydroclimatic changes in these areas. This study addresses this gap using low resolution climate archives, including speleothems, previously omitted from reconstructions. Speleothems record climate variations on decadal to centennial time scales and provide a rich dataset for the otherwise proxy data scarce region of tropical South America. By employing a multi-time scale Paleoclimate Data Assimilation approach, we synthesize climate proxy records and climate model simulations, capable of simulating water isotopologues in the atmosphere, to reconstruct 2000 years of South American climate. This includes surface air temperature, precipitation amount, drought index, isotopic composition of precipitation amount, and the intensity of the South American Summer Monsoon. The reconstruction reveals anomalous climate periods: a wetter and colder phase during the Little Ice Age (1500–1850 CE) and a drier, warmer period corresponding to the early Medieval Climate Anomaly (600–900 CE). However, these patterns are not uniform across the continent, with exceptions in northeastern Brazil and the Southern Cone, indicating regional variability. The anomalies are more pronounced than in previous reconstructions, but align with local proxy record studies, thus highlighting the importance of including speleothem proxies. The multi-timescale approach is essential for reconstructing multi-decadal and centennial climate variability. Despite methodological uncertainties regarding climate model biases and proxy record interpretations, this study marks a crucial first step in incorporating speleothems into climate field reconstructions, potentially enhancing insights into past hydroclimatic variability and hydroclimate projections. [ABSTRACT FROM AUTHOR]

Expanding the South American renewable energy matrix to ensure more sustainable socio-economic development, mitigate the climate change effects, and meet the targets set in the Paris Agreement is crucial. Hence, this study sought to estimate South America's wind speed and wind power density alterations projected by eight global climate models (GCMs) from the Coupled Model Intercomparison Project—Phase 6 (CMIP6). To this end, we applied statistical downscaling and bias correction to the GCMs outputs through the Quantile Delta Mapping method and assessed the projected changes in wind power in future climate under the Shared Socioeconomic Pathways (SSPs) SSP2-4.5 and SSP5-8.5 emission scenarios. ERA5 reanalysis data from 1995 to 2014 validated the models' historical simulations. The CMIP6 multi-model ensemble indicated an approximate 25–50% increase in wind power density in sectors such as Northeast and South Brazil and growing wind power in regions such as Argentine Patagonia, northern Venezuela, and portions of Uruguay, Bolivia, and Paraguay. Estimates of the wind power growth for the twenty-first century in those regions reiterated their potential performance in the historical period. For the SSP5-8.5 emission scenario, the ensemble projections indicated even more favorable wind power conditions in the sectors mentioned. However, individual projections of wind intensity anomalies obtained by each ensemble member showed a large spread among the GCMs, evidencing the uncertainties associated with the prospects of change in wind power on the continent. Furthermore, this study has presented a first analysis of CMIP6 projections for South American wind power generation, providing relevant information to the energy sector decision-makers. [ABSTRACT FROM AUTHOR]

Context:The Amazon region has been part of climate change debates for decades, yet attention to its social and health dimensions has been limited. Objective:This paper assesses literature on the social and health dimensions of climate change in the Amazon. A conceptual framework underscores multiple stresses and exposures created by interactions between climate change and local social-environmental conditions. Methods:Using the Thomson-Reuter Web of Science, this study bibliometrically assessed the overall literature on climate change in the Amazon, including Physical Sciences, Social Sciences, Anthropology, Environmental Science/Ecology and Public, Environmental/Occupational Health. From this assessment, a relevant sub-sample was selected and complemented with literature from the Brazilian database SciELO. Results:This sample discusses three dimensions of climate change impacts in the region: livelihood changes, vector-borne diseases and microbial proliferation, and respiratory diseases. This analysis elucidates imbalance and disconnect between ecological, physical and social and health dimensions of climate change and between continental and regional climate analysis, and sub-regional and local levels. Conclusion:Work on the social and health implications of climate change in the Amazon falls significantly behind other research areas, limiting reliable information for analytical models and for Amazonian policy-makers and society at large. Collaborative research is called for. [ABSTRACT FROM AUTHOR]

Several studies have been devoted to dynamic and statistical downscaling for analysis of both climate variability and climate change. This paper introduces an application of artificial neural networks (ANNs) and multiple linear regression (MLR) by principal components to estimate rainfall in South America. This method is proposed for downscaling monthly precipitation time series over South America for three regions: the Amazon; northeastern Brazil; and the La Plata Basin, which is one of the regions of the planet that will be most affected by the climate change projected for the end of the 21st century. The downscaling models were developed and validated using CMIP5 model output and observed monthly precipitation. We used general circulation model (GCM) experiments for the 20th century (RCP historical; 1970-1999) and two scenarios (RCP 2.6 and 8.5; 2070-2100). The model test results indicate that the ANNs significantly outperform the MLR downscaling of monthly precipitation variability. [ABSTRACT FROM AUTHOR]

The so-called ‘Little Ice Age’ (LIA) of the 15th to 19th centuries ad is well-attested from much of Europe and from some other parts of the Northern Hemisphere. It has been attributed to solar forcing, associated with reduced solar activity, notably during the Spörer, Maunder and Dalton solar minima, although other causes have also been proposed and feature strongly in recent papers. Detection of the LIA in some proxy-climate records from the Southern Hemisphere is less clear, leading to suggestions that the LIA was perhaps not a global phenomenon. Resolving this issue requires more data from the Southern Hemisphere. We present proxy-climate data (plant macrofossils; peat humification) covering the past three millennia from an ombrotrophic mire (peat bog) in Tierra del Fuego, southern South America, but focus our discussion on the period traditionally associated with the LIA. During parts of this time, the mire surface was apparently relatively dry compared with much of its 3000-year record. It was reported earlier that a particularly dry episode in the mire coincided with the 2800 cal. BP ‘solar’ event (since identified as a Grand Solar Minimum), which was attributed to solar-driven changes in atmospheric circulation, and more specifically to a shift in position of the Westerlies. Parts of the LIA record show a similar shift to dryness, and we invoke a similar cause. The shifts to and from dry episodes are abrupt. These new data support the concept of a global LIA, and for at least the intense dry episodes might reinforce the claim for solar forcing of parts of the LIA climate. [ABSTRACT FROM AUTHOR]

Palaeoclimatic records from southern tip of South America during the Last Holocene, indicate important climate intervals, such as the Medieval Climate Anomaly and Little Ice Age, which offered new scenarios to hunter-gatherer groups who inhabited the region. The aim of this paper is to explore the social practices carried out by hunter-fisher-gatherer societies of the southern part of the Atlantic Coast of Tierra del Fuego island (53–55°S, 66–74°W) in order to deal with these environmental changes. From our perspective, foragers have played an active role in designing strategies to cope with environmental fluctuations. Consequently, we argue that in a context of ecological uncertainty, these societies would have developed flexible strategies in terms of subsistence, technology and settlement patterns. In order to test this proposal, zooarchaeological and technological analysis of different archaeological assemblages dated between the 1300 to 220 BP were undertaken. The results show that these hunter-fisher-gatherer societies exploited a broad range of faunal resources using a versatile technology which encompassed tools with low production values and high use values. Likewise, the analysis of landscape organization revealed a settlement strategy centered on the most productive habitats, which were preferentially reoccupied. We suggest that these strategies, supported by cumulative knowledge and material conditions, could have enhanced social resilience and sustainability. [ABSTRACT FROM AUTHOR]

[Display omitted] • Some invasive plant species, like Pontederia crassipes , could be possibly affected by climate change. • Megamelus scutellaris is one of the most commonly used biocontrol agents for P. crassipes. • As other planthoppers, M. scutellaris is expected to host obligate mutualistic organisms, known as Yeast-like symbiotes (YLS). • YLS are first reported in M. scutellaris species and their numbers are positively correlated with their host's weight. • YLS numbers increased under elevated CO 2 , in heavier females. Water hyacinth, Pontederia crassipes , is a highly invasive plant native to South America and one of the most invasive aquatic plants in the world. For its control, the planthopper Megamelus scutellaris Berg (Hemiptera: Delphacidae), a phloem feeder also native to South America has been introduced to the USA and South Africa. Considering predicted climate change scenarios, understanding their impacts on biological control agents is crucial. An intriguing yet scarcely explored subject, is the effect of climatic changes on the obligate endosymbionts associated with sap-sucking feeders. Planthoppers establish an obligate relationship with yeast-like symbiotes (YLS), unicellular fungal microorganisms that play an important role in their development, providing missing nutrients in their diet. Considering that increased atmospheric CO 2 affects plant chemical composition, this might have a direct impact on their insect host and on their number of YLS. We evaluated the effect of two different CO 2 environments: current (cCO 2 − 400 ppm) and elevated (eCO 2 − 800 ppm) on the abundance of YLS (number of YLS cells/insect) of M. scutellaris , as well as the, age structure, sex, and weight of insects. Heavier females harbored more YLS under eCO 2 which underscores the importance of the interaction of CO 2 levels and insects' weight in shaping the abundance of YLS. Additionally, there was a significant increase in the total abundance of insects for instars III to V and adults under eCO 2 conditions. However, male number significantly exceeded that of females under both CO 2 conditions. Our results suggest a potential positive impact of eCO 2 on M. scutellaris populations, which could, in turn, enhance the control of P. crassipes. [ABSTRACT FROM AUTHOR]

Background: Global warming and climate change are threats to the world. Warmer temperatures and changes in precipitation patterns alter water availability and increase the occurrence of extreme weather events. South America and the Andes are vulnerable regions to climate change due to inequity and the uneven distribution of resources. Climate change evaluation often relies on the use of general circulation models (GCMs). However, the spatial resolution is too coarse and does not provide a realistic climate representation at a local level. This is of particular importance in mountain areas such as the Andes range, where the heterogeneous topography requires a finer spatial resolution to represent the local physical processes. To this end, statistical and/or dynamical downscaling methods are required. Several approaches and applications of downscaling procedures have been carried out in the countries of this region, with different purposes and performances. However, the main objective is to improve the representation of meteorological variables such as precipitation and temperature. A systematic review of these downscaling applications will identify the performance of the methods applied in the Andes region for the downscaling of precipitation and temperature. In addition, the meta-analysis could detect factors influencing the performance. The overall goal is to highlight promising methods in terms of fitness for use and identify knowledge gaps in the region. Methods: The review will search and examine published and grey literature on downscaling applications of temperature and precipitation in the Andes region. Predetermined criteria for eligibility will allow the screening of the evidence. Then, the method used in each application will be coded and mapped according to the country, purpose, variable, and type of downscaling. At the same time, quantitative and qualitative data will be extracted. The performance metrics are particularly interesting for this review. A meta-analysis will be conducted for those studies with comparable metrics. A narrative synthesis, maps and heatmaps will show the results. Tables, funnel plots, and meta-regressions will present the meta-analysis. Throughout the review, a critical appraisal step will categorize the validity of the evidence. [ABSTRACT FROM AUTHOR]

This paper describes a computationally efficient framework for uncertainty studies in global and regional climate change. In this framework, the Massachusetts Institute of Technology (MIT) Integrated Global System Model (IGSM), an integrated assessment model that couples an Earth system model of intermediate complexity to a human activity model, is linked to the National Center for Atmospheric Research (NCAR) Community Atmosphere Model (CAM). Since the MIT IGSM-CAM framework (version 1.0) incorporates a human activity model, it is possible to analyze uncertainties in emissions resulting from both uncertainties in the underlying socio-economic characteristics of the economic model and in the choice of climate-related policies. Another major feature is the flexibility to vary key climate parameters controlling the climate system response to changes in greenhouse gases and aerosols concentrations, e.g., climate sensitivity, ocean heat uptake rate, and strength of the aerosol forcing. The IGSM-CAM is not only able to realistically simulate the present-day mean climate and the observed trends at the global and continental scale, but it also simulates ENSO variability with realistic time scales, seasonality and patterns of SST anomalies, albeit with stronger magnitudes than observed. The IGSM-CAM shares the same general strengths and limitations as the Coupled Model Intercomparison Project Phase 3 (CMIP3) models in simulating present-day annual mean surface temperature and precipitation. Over land, the IGSM-CAM shows similar biases to the NCAR Community Climate System Model (CCSM) version 3, which shares the same atmospheric model. This study also presents 21st century simulations based on two emissions scenarios (unconstrained scenario and stabilization scenario at 660 ppm CO2-equivalent) similar to, respectively, the Representative Concentration Pathways RCP8.5 and RCP4.5 scenarios, and three sets of climate parameters. Results of the simulations with the chosen climate parameters provide a good approximation for the median, and the 5th and 95th percentiles of the probability distribution of 21st century changes in global mean surface air temperature from previous work with the IGSM. Because the IGSM-CAM framework only considers one particular climate model, it cannot be used to assess the structural modeling uncertainty arising from differences in the parameterization suites of climate models. However, comparison of the IGSM-CAM projections with simulations of 31 CMIP5 models under the RCP4.5 and RCP8.5 scenarios show that the range of warming at the continental scale shows very good agreement between the two ensemble simulations, except over Antarctica, where the IGSM-CAM overestimates the warming. This demonstrates that by sampling the climate system response, the IGSM-CAM, even though it relies on one single climate model, can essentially reproduce the range of future continental warming simulated by more than 30 different models. Precipitation changes projected in the IGSM-CAM simulations and the CMIP5 multi-model ensemble both display a large uncertainty at the continental scale. The two ensemble simulations show good agreement over Asia and Europe. However, the ranges of precipitation changes do not overlap - but display similar size - over Africa and South America, two continents where models generally show little agreement in the sign of precipitation changes and where CCSM3 tends to be an outlier. Overall, the IGSM-CAM provides an efficient and consistent framework to explore the large uncertainty in future projections of global and regional climate change associated with uncertainty in the climate response and projected emissions. [ABSTRACT FROM AUTHOR]

This paper identifies two sources of uncertainties in model projections of temperature and precipitation: internal and inter-model variability. Eight models of WCRP-CMIP3 and WCRP-CMIP5 were compared to identify improvements in the reliability of projections from new generation models. While no significant differences are observed between both datasets, some improvements were found in the new generation models. For example, in summer CMIP5 inter-model variability of temperature was lower over northeastern Argentina, Paraguay and northern Brazil, in the last decades of the 21st century. Reliability of temperature projections from both sets of models is high, with signal to noise ratio greater than 1 over most of the study region. Although no major differences were observed in both precipitation datasets, CMIP5 inter-model variability was lower over northern and eastern Brazil in summer (especially at the end of the 21st century). Reliability of precipitation projections was low in both datasets. However, the signal to noise ratio in new generation models was close to 1, and even greater than 1 over eastern Argentina, Uruguay and southern Brazil in some seasons. [ABSTRACT FROM AUTHOR]

Climate is one of the most of influential natural factors on society and economy. One of the consequences of climate anomalies is the emergence of diseases and epidemics, especially in agrarian societies. The current concern with long-term climate change and its measurable consequences on health and disease gives new relevance to the question of how agrarian societies fared during sharp droughts and other climatic hardships, especially those subject to the disruptive processes of colonization. Not many studies have been done in Latin America that relate climate, epidemics and mortality from a historical perspective. This paper explores the association between climatic anomalies, epidemic events, and native demographic decline in the Alto Peru region in the highlands of Bolivia, in the late eighteenth and early nineteenth century. Studies of historic climatology indicate that adverse climate events became more frequent in the southern areas of South America during these centuries. There were extreme oscillations in precipitation, especially beginning in the 1750's which significantly impacted the largest group of people in late colonial Alto Peru: the indigenous population, whose vulnerability increased in face of local climatic anomalies and the resulting epidemiological risk. Both the quantitative and the qualitative analysis show associations between climatic and epidemic events. [ABSTRACT FROM AUTHOR]

Recent studies have shown that global warming and associated sea-surface temperature (SST) changes may trigger an important rainfall increase in southeastern South America (SESA) during the austral summer (December-January-February, DJF). The goal of this paper is to provide some insight into processes which may link global and SESA changes. For this purpose, a 'two-way nesting' system coupling interactively the regional and global versions of the LMDZ4 atmospheric model is used to study the response to prescribed SST changes. The regional model is a variable-grid version of the global model, with a zoom focused over South America. An ensemble of simulations forced by distinct patterns of DJF SST changes has been carried out using a decomposition of full SST changes into their longitudinal and latitudinal components. The full SST changes are based on projections for the end of the twenty-first century from a multi-model ensemble of WCRP/CMIP3. Results confirm the presence of a major rainfall dipole structure, characterized by an increase in SESA and a decrease in the South Atlantic Convergence Zone region. Rainfall changes found in the WCRP/CMIP3 models are largely explained as a response of this dipole structure to the zonally-asymmetric (or longitudinal) component of SST changes. The rainfall response to the zonal-mean (or latitudinal) SST changes (including the global warming signal itself) shows an opposite contribution. The processes explaining the role of zonally-asymmetric SST changes involve remote effects of SST warming over the equatorial Indian and Pacific oceans inducing an atmospheric wave-train extended across the South Pacific into South America. [ABSTRACT FROM AUTHOR]

Aim The aim of this paper is to investigate the influence and extent of past climatic changes on South American biota. To this end, we establish phylogeographical hypotheses for a monophyletic group of four cactophilic species of Drosophila (the Drosophila serido haplogroup) found in xeromorphic vegetation in Brazil. The effects of Quaternary palaeoclimatic oscillations on the demographic fluctuations of our biological model and its sister group Drosophila antonietae are investigated. Location Areas of eastern Brazil with open vegetation, including seasonally dry tropical forest ( SDTF) areas and montane savannas, which are disjunctly distributed in eastern Brazil. We also analysed populations of sand dune vegetation from littoral areas in Brazil. Methods Nucleotide information from 630 bp of the cytochrome c oxidase subunit I gene from 441 individuals was used to perform a series of statistical analyses to infer a phylogeographical hypothesis for each species and to date the divergence time between the D. serido and D. antonietae haplogroups. Results All of the analysed species experienced population expansion during the Pleistocene, probably following the historical migratory routes that have been proposed for the expansion of SDTFs in Brazil. A bottleneck event in the Holocene was inferred for Drosophila seriema, probably due to ecological factors related to the geographical distribution of the host plant. The divergence time for the D. serido and D. antonietae haplogroups was calculated to have occurred during the early Pleistocene. Main conclusions Geographical and chronological evidence suggests that the major vicariant events between the D. serido and D. antonietae haplogroups, as well as the demographic fluctuations in each of the species within these lineages, could be related to the causal effects of Quaternary palaeoclimatic changes on the spatial dynamics of the SDTFs in Brazil. [ABSTRACT FROM AUTHOR]