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While ubiquitous among ancient Maya sites in Mesoamerica, archaeological analysts frequently overlook the interpretive potential of ground stone tools. The ancient Maya often made these heavy, bulky tools of coarse‐grained, heterogeneous materials that are difficult to chemically source, unlike obsidian. This paper describes an application of handheld, energy‐dispersive X‐ray fluorescence (XRF) to provenance ground stone artifacts (tools and architectural blocks) composed of granite: a nonhomogenous, phaneritic stone. We present a multicomponent methodology that independently tested whole‐rock, thin‐sectioned, and powdered samples by petrographic microscope, conventional, lab‐based XRF, and portable XRF units, which yielded comparable results. After establishing distinct geochemical signatures for the three geographically restricted granite plutons in Belize, we devised a field‐based XRF application on a whole rock that could replicate the compositional readings of lab‐based XRF on powdered materials with sufficient accuracy and reliability. We applied this multishot XRF technique to granite ground stone items from a range of ancient Maya sites throughout Belize; we discuss two specific case studies herein. Our results underscore the widespread potential of multishot XRF applications for determining the provenance of coarse‐grained, heterogeneous rock materials. These results can help push the boundaries from one‐dimensional, functional explanations of ground stone items to their social and ideological dimensions, alongside deeper understandings of granite resource management. [ABSTRACT FROM AUTHOR]

The North American Monsoon (NAM) is a critical component of the hydrologic cycle in southwestern North America. However, our understanding of the long‐term evolution of this monsoon system is incomplete due to a paucity of long‐term paleoclimatic records from the core and periphery of the NAM domain. C. Routson et al. (2022, https://doi.org/10.1029/2022gl099772) leverage a new compilation of Holocene proxy records to generate a new composite index of NAM evolution over the Holocene. They identify a relationship between NAM strength and the latitudinal temperature gradient over the Holocene. The authors suggest that shifts in the strength of the westerlies altered NAM convection via ventilation, a process whereby the large‐scale circulation imports low moist entropy air into the monsoon domain. These results highlight the importance of paleoclimatic records, especially from past "warm" intervals, for generating new insights about the evolution of regional monsoons. Plain Language Summary: The North American Monsoon is a circulation that brings summer rain to regions of the US southwest and western Mexico. Despite the fact that this circulation provides a majority of the precipitation in many parts of the arid southwest, we do not fully understand the factors that govern long‐term changes in this monsoon. A new paper by C. Routson et al. (2022, https://doi.org/10.1029/2022gl099772) uses proxy indicators of past summer rainfall, stretching from Central America to Arizona, to reconstruct changes in the monsoon over the geologic epoch known as the Holocene, or the last 11,000 years of Earth history. The results of this study suggest that Holocene changes in the temperature difference between the equator to pole, known as the "latitudinal temperature gradient," exerted an important influence over monsoon strength in the southwest. This has implications for the future of the summer monsoon, especially as the high latitudes of the northern hemisphere are expected to warm in the future. Key Point: The strength North American Monsoon tracks changes in the position of the midlatitude westerlies over the Holocene [ABSTRACT FROM AUTHOR]

Maya blue is a pigment found in different archaeological sites of different cultures from Mesoamerica, and also in colonial buildings in Mexico and Cuba. The pigment is made from a thermally treated mixture of indigo and palygorskite. Pigment samples from Aztec and non‐Aztec archaeological sites as well as reference Yucatecan palygorskites were studied in this paper to assess their differences. The characterization of the samples was carried out by a combination of a crystal–chemical‐point analyses using electron microscopy to obtain the structural formulae of the palygorskite crystals, and studied using high‐resolution X‐ray diffraction. The data show evidence that the palygorskite used by non‐Aztec cultures, such as the Maya, is compatible with palygorskite from known sources in the Yucatan Peninsula, while the palygorskite used by the Aztec culture is different in its structure and has an origin that is still unknown. [ABSTRACT FROM AUTHOR]

Ethnohistoric sources describe the market of Postclassic Cholula as featuring goods from throughout Mesoamerica. Furthermore, the merchant guilds centered in the city, followers of the god Yacatecuhtli/Quetzalcoatl, were elevated to princely status. Contact‐period sources also describe the political organization of the city, in which these merchant princes played a prominent role. The far‐flung influence of the religio‐commercial diaspora is represented through the distinctive symbolism of the Mixteca‐Puebla stylistic tradition, found throughout Postclassic Mesoamerica and as far south as Pacific Nicaragua. This paper uses the ethnohistorical evidence to construct a model of Cholula's urban economy and its international influence, with archaeological evidence to critically evaluate the sources. [ABSTRACT FROM AUTHOR]

Nearly three decades of research have identified evidence of commercial institutions and exchange at cities throughout Mesoamerica. This introduction examines three major areas of investigation for commercial institutions in ancient Mesoamerican cities: marketplaces and urban geography; currencies, standards and credit; and the social dimensions of urban commerce. It discusses the different ways in which the contributing authors examine different commercial economies of ancient Mesoamerica through the prism of its urban centers, and the potential of this approach for further archaeological research. [ABSTRACT FROM AUTHOR]

Population‐based cancer registries (PBCRs) are the only means to provide reliable incidence and survival data as a basis for policy‐making and resource allocations within cancer care. Yet, less than 3% and 10% of the respective populations of Central America and South America are covered by high‐quality cancer registries. The Global Initiative for Cancer Registry Development provides support to improve this situation via the International Agency for Research on Cancer Regional Hub for Latin America. In this paper, we summarize activities (advocacy, technical assistance, training and research) over the last 5 years, their impact and current challenges, including the implementation of new PBCR in four countries in the region. Despite the favorable political support to cancer registration in many countries, the sustainability of cancer registration remains vulnerable. Renewed efforts are needed to improve data quality in Latin America while ensuring maximum visibility of the data collected by disseminating and promoting their use in cancer control. [ABSTRACT FROM AUTHOR]

The paper suggests that there are specific features of violence, both personal and organized that have tools in the cultural formation of the Central American peoples. Its focus is on the three neighboring countries of Guatemala, Honduras, and El Salvador and on the ideological violence of the twentieth century. The paper considers various aspects of the social character of the Spanish Americans of this area, their concepts of manliness, and their religion, as these affect both rich and poor, and contrasts these features with the attitudes of the indigenous Indian community. Having established that political violence is endemic in the region, the paper considers the role of Hispanic culture in shaping this violence. Emphasis is placed on the notion of machismo, which is identified not with pleasure seeking but with defiance of death. The attitudes of the people of this area toward death shape their attitudes toward violence. They are shown to have a fascination with the instruments of death, especially the machete among the lower classes and the gun among the university students. These attitudes are contrasted with the relatively non-violent attitudes of the Indians. The studies cited in this paper show the Indians as less interested in competition and aggression that the Hispanic population. In the last analysis, the violence of the Central American is intensely personal and can be shown to derive from the basic social and cultural fabric of the society. [ABSTRACT FROM AUTHOR]

Educators involved in the improvement of science instruction need to explore how science education could better align with the needs and interests of specific communities, especially in areas of Central America where local knowledge has been expunged from schools. In this paper, I draw upon Culturally Sustaining and Revitalizing Pedagogies to explore a single community's visions for science education and how these visions may be used as pathways for restoring relevant science education practices. To do this study, a case study approach was used to collect 150 h of science lesson observations at three schools in a small Nicaraguan community and interview 18 science teachers and community members. Many of these teachers and community members provided detailed accounts of local science knowledge or methods of teaching science that had been replaced with Westernized curriculum and pedagogies to the detriment of learning and their community. Results indicate two overarching visions: (1) a vision for reviving Scholar Orchards and (2) a vision for learning science with community resources. These findings highlight the need to partner with local teachers and community members when designing, implementing, and evaluating science education because they possess sophisticated visions for making science more relevant, sustaining, and revitalizing within their community context. [ABSTRACT FROM AUTHOR]

The relationship between standards, economic development, and trade is at the forefront of policy debate. Standards can accelerate economic efficiency and trade and also act as discriminatory barriers. This paper examines standards in the context of development in Central America. Key aspects of disputes over standards at the World Trade Organization are discussed, along with the reasons why standards matter to development and trade prospects for Central America. The paper recommends ways to leverage shared infrastructure in standards and assist these countries to implement their WTO obligations. [ABSTRACT FROM AUTHOR]

This paper reviews the foreign debt burden in Central America with special emphasis on Honduras and Nicaragua. These countries have a large debt overhang and they have lagged behind the rest of the region in terms of economic growth. Our work suggests that Honduras and Nicaragua require alleviation of their foreign debt as a prerequisite to achieve sustained economic growth. The paper also reviews the initiative aimed at reducing the debt burden of the highly indebted poor countries (the HIPC Initiative) and evaluates alternative scenarios of debt reduction for both Honduras and Nicaragua. It ends with a critical assessment of the implications of the fiscal and openness criteria established in the HIPC Initiative. [ABSTRACT FROM AUTHOR]

Copyright of Tropical Medicine & International Health is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Plants, People, Planet is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: Censuses of tropical forest plots reveal large variation in biomass and plant composition. This paper evaluates whether such variation can emerge solely from realistic variation in a set of commonly measured soil chemical and physical properties.Controlled simulations were performed using a mechanistic model that includes forest dynamics, microbe‐mediated biogeochemistry, and competition for nitrogen and phosphorus. Observations from 18 forest inventory plots in Guanacaste, Costa Rica were used to determine realistic variation in soil properties.In simulations of secondary succession, the across‐plot range in plant biomass reached 30% of the mean and was attributable primarily to nutrient limitation and secondarily to soil texture differences that affected water availability. The contributions of different plant functional types to total biomass varied widely across plots and depended on soil nutrient status. In Central America, soil‐induced variation in plant biomass increased with mean annual precipitation because of changes in nutrient limitation.In Central America, large variation in plant biomass and ecosystem composition arises mechanistically from realistic variation in soil properties. The degree of biomass and compositional variation is climate sensitive. In general, model predictions can be improved through better representation of soil nutrient processes, including their spatial variation. [ABSTRACT FROM AUTHOR]

Africa is one of the most productive lightning regions on Earth, yet it has a lower terrestrial gamma ray flash (TGF)‐to‐lightning ratio especially compared with Central America. In this paper, we have analyzed the global distribution of different meteorological parameters in order to explain the TGF/lightning ratio asymmetry. We show here that a drier surface and larger Convective Available Potential Energy in Africa may produce thunderstorms with intense electric charge regions but elevated in the atmosphere and closer to each other, which allows for higher flash rates and less energetic, shorter, and smaller flashes. The results we present here suggest that continental thunderstorms in Africa more rarely fulfill the lightning and thundercloud requirements for TGF production inferred from observations and models. Key Points: Drier surface and high CAPE in Africa allows for stronger updrafts, and large concentrations of aerosols enhance electrification processesThunderstorms in Africa may have intense electrification, but charge regions are elevated in the atmosphere and closer to each otherThunderstorms in Africa do not accomplish the favorable conditions for TGF production [ABSTRACT FROM AUTHOR]

Central and eastern United States (CEUS) have experienced large intraplate earthquakes. Yet, at present there is no comprehensive model to explain stresses, strain, and seismicity in this intraplate setting. Models to explain the intraplate stresses in CEUS include glacio‐isostatic adjustment, ridge push effects, local stresses along preexisting fracture zones, and large‐scale convection. In this paper, we present a self‐consistent model of the dynamics of CEUS that explains the stress field responsible for these intraplate earthquakes. The earthquakes represent slow, ongoing deformation associated with forces arising from a combination of lithosphere topography and structure, together with the effects of density‐driven mantle flow. Using GPS data, we calculate strain rates that are likely to arise from tectonic effects and conclude that intraplate strain rates associated with tectonic effects are unlikely to exceed 1 × 10−9 year−1. We test several models of lateral viscosity variations by comparing model stress orientation output with earthquake moment tensors, SHmax directions from stress inversion, and P axes of earthquakes. A model that satisfies stress and earthquake constraints and also strain rate magnitude constraints requires high viscosity (1025 Pa·s) craton and old oceanic lithosphere of the western Atlantic block and weaker (5 × 1024 Pa·s) accreted Appalachian terrane. Other strength contrasts within the lithosphere are likely present. Incorporation of these into future models using constraints from seismology, along with refined geodetic measurements and improved estimates of crust and upper mantle densities, is needed to further refine long‐term dynamic models and better evaluate the hazards associated with this very slow, ongoing permanent deformation within the eastern and central United States. Key Points: GPE gradients and coupling with large‐scale mantle flow generate stresses responsible for intraplate earthquakes in North AmericaIntraplate strain rates in CEUS are dominated by GIA, but those associated with tectonic effects are unlikely to exceed 1 x 10‐9 year‐1First‐order strength contrasts in the lithosphere are needed to satisfy stress and strain indicators from earthquakes [ABSTRACT FROM AUTHOR]

Aim: This systematic review aimed to provide an overview of the immunisation of internationally adopted children and to discuss possible vaccination strategies.Methods: A literature search was performed covering papers published in English from 1988 to 15 June 2018 using the Ovid MEDLINE, EMBASE and Cochrane Library databases. This identified 749 studies and 41 full texts were evaluated.Results: Overall, 19 studies conducted between 1988 and 2016 fulfilled our inclusion criteria. These covered 7663 children aged 1.1-5.7 years adopted from Asia, Eastern Europe, Africa and South and Central America. Tetanus protective antibody levels ranged from 35 to 95%, and similar data were reported for diphtheria. A higher percentage of adoptees had protective antibody levels for polio (50-93%) and measles (62-95%). More than a third (35%) did not have protective antibody titres for hepatitis B. Only one study investigated adoptees with protective antibodies against haemophilus influenza, and it reported that this was around 66%.Conclusion: The appropriate immunisation of internationally adopted children is a major challenge for primary health care and a number of different approaches have been suggested, with no clear conclusions. Further studies on the cost-effectiveness of different approaches should be performed to optimise screening strategies and develop recommendations. [ABSTRACT FROM AUTHOR]

Copyright of Island Arc is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Self-reported retrospective survey data is widely used in empirical work but may be subject to cognitive biases, even over relatively short recall periods. This paper examines the role of anchoring bias in self-reports of objective and subjective outcomes under recall. We use a unique panel-survey dataset of smallholder farmers from four countries in Central America collected over a period of three years. We exploit differences between recalled and concurrent responses to quantify the degree of mental anchoring in survey recall data. We assess whether respondents use their reported value for the most recent period as a cognitive heuristic when recalling the value from a previous period, while controlling for the value they reported earlier. The results show strong evidence of sizeable anchoring bias in self-reported retrospective indicators for both objective measures (income, wages, and working hours) and subjective measures (reports of happiness, health, stress, and well-being). We also generally observe a larger bias in response to negative changes for objective indicators and a larger bias in response to positive changes for subjective indicators. [ABSTRACT FROM AUTHOR]

ABSTRACT In this paper, we contrast two different views in the debate on official dollarization. The Mundell framework of optimum currency areas and a model on boom-bust cycles, by Schneider and Tornell, who take account of credit market imperfections prevalent in middle income countries. We highlight that the role of the exchange rate is strikingly different in the two models. Although in the Mundell framework, the exchange rate is expected to smooth the business cycle, the other model predicts that the exchange rate plays an amplifying role. We empirically evaluate both models for eight highly dollarized Central American economies. We document the existence of credit market imperfections and find that shocks from the exchange rate indeed amplify business cycles in these countries. Using a new method of Cubadda, we furthermore test for cyclical comovement and reject the hypothesis that the countries form an optimum currency area with the United States according to the Mundell definition. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objectives: To explore evolutionary hypotheses for the high frequencies of a substitution in the methylenetetrahydrofolate reductase (MTHFR) gene, in Mexican and Central American Indigenous populations. Materials and methods: We obtained allele frequencies for the C677T variant in the MTHFR gene and ecological information for 37 indigenous samples from Mexico and Central America. We calculated Hardy–Weinberg equilibrium and computed Fst statistics. We computed correlations between the samples' allele frequencies and ecological and geochemical variables. Results: Many of the samples have extremely high frequencies of the T allele (q¯ = 0.62, median = 0.66). In this region, the frequency of the T allele decreases from Southeast to Northwest and is significantly correlated with longitude, latitude, altitude, and insolation. Conclusions: The native people of Central America and Mexico evolved high frequencies of an allele which has been shown to produce deleterious clinical effects including neural tube effects, cardiovascular events, and cancer. This allele has a clinal distribution in the region, perhaps associated with solar irradiation. As (Contreras‐Cubas et al., 2016) noted, the traditional diet of these populations, which is high in folate, has likely mitigated the negative effect of the allele. It is of primary importance that their rights to their homeland and traditional diets be respected. It is a matter of Public Health to investigate whether this allele is a factor in the current wave of cardiovascular diseases affecting the majority population of this region, since it descends from the Native peoples and the Mediterranean population, which also has high frequencies of the allele. [ABSTRACT FROM AUTHOR]

Among geographers, recent focus on the illicit and illegal has tended to fall into two camps. Economic geographers focus on regimes of illicitness and corresponding production of specific forms of economic space; political ecologists and land change scholars, on the other hand, scrutinised how illicit commodity flows shape land and resource use, especially in the global South. This paper offers an initial integration of these two relatively separate subfields, specifically in terms of their complementary attention to uneven development. We use the concept of "global commodity chains" to explore the ways in which the regulation of agricultural commodities shapes how they are trafficked and embed in space, with particular attention to sites of international transshipment. When a commodity is illegal, spaces of transit take on significant analytical importance. As a heuristic, we present a comparative mapping of two agricultural commodity chains linking Colombia and the USA: coffee and cocaine. Their comparison highlights how "illicitness" fundamentally transforms cocaine's spatiality, requiring risk evasion that results in characteristically enlarged transit spaces and huge differentials between producer and consumer price. We show how rents circulate in those transit spaces, socially and ecologically embedding in diffuse, fluid networks with severe consequences for people and environments. We conclude with implications for work on illicit commodities and the collateral social and environmental harms they produce. [ABSTRACT FROM AUTHOR]

There is an increasing interest in the impact assessment of management training programs. Among various types of training, this study focuses on those featuring Kaizen, a standard approach to production management and quality control whose name derives from the Japanese word meaning "improvement." Previous studies of Kaizen training programs evaluate training impacts on management practices, business performance, and the willingness to pay for training, and do not pay attention to impacts on workers. Using the firm‐level data, this study attempts to assess the impacts of an onsite training program held at small and medium enterprises in eight Central American and Caribbean countries. Treated firms are compared with those firms that are selected by the sponsor organization according to the same criteria as the treated counterparts but not yet treated. Propensity score matching is employed to increase comparability between the two groups. This paper presents suggestive evidence that the training program improved work practices and the attitude of workers toward work. It also suggests that the treated firms weaken the linkage between sales revenues and wages, probably to induce workers to pay attention to activities that do not immediately increase sales, such as maintenance and coaching of other workers. [ABSTRACT FROM AUTHOR]

In evaluating the contributions to this issue, this chapter questions the predictable co‐occurrence of cities with markets and states, a long‐held position in western social theory. However, an extreme relativism is also flawed, and the projection of anti‐capitalist fantasies on past, other peoples have equally distorted interpretations of the archaeological record and blinded researchers to the reality of market economies in societies including the Maya. Ultimately, the power of the comparative method entails more than the identification of commonalities between different market traditions. It can also serve to illuminate how market economics were embedded in distinct cultural, ideological, and material worlds. Calculating self‐interest, supply‐and‐demand, and impersonal exchange do not operate according to a single behavioral logic but are shaped by ideologies of identity and desire specific to distinct regimes of value. Therefore, attention to the cultural and spatial context of economic transactions—in the original spirit of Polanyi—remains indispensable to interpreting how markets may have shaped historically particular constructions of personhood, community, inequality, place, and the ontological status of commodities. In the end, I argue that archaeologists also need to investigate the political affordances of markets as specific urban places and not simply as epiphenomena to a priori political or economic institutions. [ABSTRACT FROM AUTHOR]

In this article, we draw on the volatile complexity of African migrant trajectories in Central America to broaden the scope of transnational scholarship. These trajectories are characterised by mobilities as well as immobilities, taking shape in particular local contexts. By focusing on the interplays between displacement and emplacement that are part of these trajectories, we aim to increase our understanding of the extent to which migrants still 'on the move' experience both temporal embeddedness and cross‐border connectedness, thereby acknowledging and unravelling transnational lives as they 'touch the ground' en route. To do so, we build on long‐standing scholarly commitments in Central and South America and recent field research in Costa Rica. We go into selected empirical cases to discuss the dynamics of travelling, dwelling and travelling again as part of African migrant trajectories across Central America. We then explore the value of a 'shifting' transnational social field perspective and indicate some challenges for future trajectory research. [ABSTRACT FROM AUTHOR]

Common distributional patterns have provided the foundations of our knowledge of Neotropical biogeography. A distinctive pattern is the "circum‐Amazonian distribution", which surrounds Amazonia across the forested lowlands south and east of the basin, the Andean foothills, the Venezuelan Coastal Range, and the Tepuis. The underlying evolutionary and biogeographical mechanisms responsible for this widespread pattern of avian distribution have yet to be elucidated. Here, we test the effects of biogeographical barriers in four species in the passerine family Thamnophilidae by performing comparative demographic analyses of genome‐scale data. Specifically, we used flanking regions of ultraconserved regions to estimate population historical parameters and genealogical trees and tested demographic models reflecting contrasting biogeographical scenarios explaining the circum‐Amazonian distribution. We found that taxa with circum‐Amazonian distribution have at least two main phylogeographical clusters: (1) Andes, often extending into Central America and the Tepuis; and (2) the remaining of their distribution. These clusters are connected through corridors along the Chaco–Cerrado and southeastern Amazonia, allowing gene flow between Andean and eastern South American populations. Demographic histories are consistent with Pleistocene climatic fluctuations having a strong influence on the diversification history of circum‐Amazonian taxa, Refugia played a crucial role, enabling both phenotypic and genetic differentiation, yet maintaining substantial interconnectedness to keep considerable levels of gene flow during different dry/cool and warm/humid periods. Additionally, steep environmental gradients appear to play a critical role in maintaining both genetic and phenotypic structure. [ABSTRACT FROM AUTHOR]

The palaeobiogeography of the alveolinoid Borelis species reveals the evolutionary patterns leading to the two extant representatives, which occur in shallow‐water tropical carbonate, coral reef‐related settings. Type material and new material of fossil Borelis species, along with Recent specimens were studied to assess their taxonomic status, species circumscriptions (based on proloculus size, occurrence of Y‐shaped septula, and the index of elongation), palaeobiogeography and evolutionary dynamics. The species dealt with here are known from exclusively fossil (B. pygmaea, B. inflata, B. philippinensis, B. melo, B. curdica), and from fossil and modern (B. pulchra, B. schlumbergeri) specimens. For the first time, fossil and Recent Borelis specimens are illustrated via micro‐computed tomography scanning images. Depending on the occurrence of Y‐shaped septula, two lineages are distinguished. Deriving from the middle–upper Eocene Borelis vonderschmitti, the first lineage includes B. inflata, B. pulchra and B. pygmaea, lacking Y‐shaped septula. The first species bearing Y‐shaped septula is the Rupelian B. philippinensis of the western Indo‐Pacific. The westward migrants of B. philippinensis into the Mediterranean gave rise to B. melo (Aquitanian–Messinian) and B. curdica (Burdigalian–Tortonian). These two species became isolated from the Indo‐Pacific by the Langhian eastern closure of the Mediterranean basin and disappeared during the Messinian Salinity Crisis. Since the Tortonian, B. schlumbergeri, which descended from B. philippinensis, has inhabited the Indo‐Pacific along with B. pulchra. From the central Pacific Ocean, B. pulchra reached the Caribbean area before the early Piacenzian closure of the Central America seaway. [ABSTRACT FROM AUTHOR]

The availability of freshwater from glaciers and snowmelt is of vital importance for people and ecosystems in the context of global climate change. Here, we focus on 25 glaciers located in different climates and latitudes and investigate their recent (1958–2020) and future projected trends (2020–2050 and 2070–2100) in monthly precipitation (Pr), maximum and minimum temperatures, ice mass loss, and their relationships with cloud properties. The study sites are located in Temperate Europe (France), the Inner (Ecuador, Venezuela, and Colombia) and Outer Tropics (Bolivia and Peru), Central America (Mexico), tropical Southeast Asia (Indonesia), Equatorial Africa (Uganda), and the Southern dry and Patagonian Andes (Chile and Argentina). The climate analyses are based on TerraClimate data (Monthly Climate and Climatic Water Balance for Global Terrestrial Surfaces) and 28 CORDEX (Coordinated Regional Climate Downscaling Experiment) climate simulations. Our findings reveal that, extrapolating current glacier volume change trends, almost half of the studied glaciers are likely to vanish (95%–100% volume loss) by 2050, with widespread warming and drying trends since 1958. A shift toward wetter conditions at Pico Humboldt (Venezuela) and Martial Este (Argentina) identifiable in the CORDEX simulation will very likely not have a limiting impact on glacier mass loss owing to increasing temperatures, which will raise the elevation of the rain/snow limit. Our results provide useful new information to better understand glacier‐climate relationships and future scenarios dominated by ice mass loss trends across the globe. These findings suggest serious consequences for future water availability, which exacerbate the vulnerability of local populations and ecosystems. Plain Language Summary: In this study, we employ the monthly TerraClimate data, Coordinated Regional Climate Downscaling Experiment climate projections, and glaciological data to investigate potential associations between climate variables (precipitation and temperatures), cloud conditions, and changes in glacier volume across 25 glaciers worldwide. Over the historical period (1958–2020) and in the future decades (2020–2050 and 2070–2100), none of the glacierized sites exhibit both cooling and wetting trends. In contrast, widespread warmer and drier conditions in recent and future decades are identified for the studied glaciers located in Temperate Europe, Central America, the Southern dry Andes, and Northern Patagonia, where almost half of the glaciers are likely to vanish by 2050 if current or recent trends persist. Relationships between the temperature range and changes in cloud cover are significant at the Outer Tropics and Northern Patagonian sites. These findings could be used by the scientific community to improve climate change projections and by decision‐makers to develop adaptation and mitigation strategies to cope with the consequences of climate change and support regional socioeconomic development. Key Points: TerraClimate and Coordinated Regional Climate Downscaling Experiment data reveal widespread warming and drying trends since 1958 over 25 glaciers located in different climatesConsidering current trends, almost half of the studied glaciers are likely to vanish by 2050. Additional warming would increase this numberTemperatures are more influential predictors than precipitation for glaciers volume [ABSTRACT FROM AUTHOR]

Mountains play a vital role in shaping regional and global climate, altering atmospheric circulation and precipitation patterns. To this end, identifying projected changes in mountain precipitation is significantly challenging due to topographic complexity. This study explains how mountain precipitation could respond to rising greenhouse gases. Using a series of century‐long fully coupled high‐resolution simulations conducted with the Community Earth System Model, we aim to disentangle future changes in mountain precipitation in response to atmospheric carbon dioxide (CO2) perturbations. Our research findings indicate that the warming observed in global mountains is more pronounced when compared to the mean warming rates experienced globally and in the ocean under elevated CO2. We identify five low‐latitude mountain ranges with elevation‐dependent precipitation response, including New Guinea, East Africa, Eastern Himalayas, Central America, and Central Andes. Those mountains are expected to have a mixture of increasing and decreasing precipitation in response to CO2‐induced warming, especially over the summit and steep topography. To elucidate the mechanisms controlling future changes in mountain precipitation, we propose "Orographic moisture omega feedback" in which an increase in low‐level relative humidity enhances local precipitation by strengthening the upward motion through moist processes for the wetting response and vice versa for the drying response. The effects of Mountain precipitation changes can be extended to hydrology and could lead to significant consequences for human societies and ecosystems. Plain Language Summary: Recently, Mountain warming with increasing greenhouse warming has taken attention. However, predicting changes in mountain rainfall is hard and limitedly explored. There is a need to connect predominately idealized studies of change in orographic precipitation with warming to State‐of‐the‐art global climate model simulation (GCM). Therefore, we ran experiment simulations to study how mountain rainfall will change in the future due to the increase in atmospheric carbon dioxide. The impact of warming on mountain precipitation is complex and could result in a combination of results, such as increased and decreased precipitation. To our knowledge, this is the first kind of study that connects the change in mountain precipitation with future greenhouse warming using a 25 km high‐resolution GCM. This study found that the changes in rainfall are expected in high‐elevation mountains located in low‐latitude regions with steep slopes. This analysis concentrates on five major mountain ranges: New Guinea, East Africa, the Himalayas, Central America, and Central Andes. Furthermore, the feedback mechanism could explain how low‐level humidity affects Mountain rainfall and atmospheric convection. By studying mountain meteorology, we can gain insights into the complex interactions between mountains and the atmosphere, contributing to the overall understanding of our earth system. Key Points: This study uses a high‐resolution model experiment to explain how mountain precipitation could respond to rising atmospheric carbon dioxide (CO2) concentrationProjected precipitation changes are dominated over low‐latitude mountains, especially the summit and steep topographyWe propose a mechanism, "Orographic moisture omega feedback," that explains the unprecedented anomalous changes in the mountain climate [ABSTRACT FROM AUTHOR]

Please cite this paper as: Laguna-Torres et al. (2011) Influenza and other respiratory viruses in three Central American countries. Influenza and Other Respiratory Viruses 5(2), 123-134. Despite the disease burden imposed by respiratory diseases on children in Central America, there is a paucity of data describing the etiologic agents of the disease. To analyze viral etiologic agents associated with influenza-like illness (ILI) in participants reporting to one outpatient health center, one pediatric hospital, and three general hospitals in El Salvador, Honduras, and Nicaragua Between August 2006 and April 2009, pharyngeal swabs were collected from outpatients and inpatients. Patient specimens were inoculated onto cultured cell monolayers, and viral antigens were detected by indirect and direct immunofluorescence staining. A total of 1,756 patients were enrolled, of whom 1,195 (68.3%) were under the age of 5; and 183 (10.4%) required hospitalization. One or more viral agents were identified in 434 (24.7%) cases, of which 17 (3.9%) were dual infections. The most common viruses isolated were influenza A virus (130; 7.4% of cases), respiratory syncytial virus (122; 6.9%), adenoviruses (63; 3.6%), parainfluenza viruses (57; 3.2%), influenza B virus (47; 2.7% of cases), and herpes simplex virus 1 (22; 1.3%). In addition, human metapneumovirus and enteroviruses (coxsackie and echovirus) were isolated from patient specimens. When compared to the rest of the population, viruses were isolated from a significantly higher percentage of patients age 5 or younger. The prevalence of influenza A virus or influenza B virus infections was similar between the younger and older age groups. RSV was the most commonly detected pathogen in infants age 5 and younger and was significantly associated with pneumonia ( p < 0.0001) and hospitalization ( p < 0.0001). Genetic analysis of influenza isolates identified A (H3N2), A (H1N1), and B viruses. It also showed that the mutation H274Y conferring resistance to oseltamivir was first detected in Honduran influenza A/H1N1 strains at the beginning of 2008. These data demonstrate that a diverse range of respiratory pathogens are associated with ILI in Honduras, El Salvador, and Nicaragua. RSV infection in particular appears to be associated with severe disease in infants in the region. [ABSTRACT FROM AUTHOR]

The article discusses various reports published within the issue that focus specifically on youth violence in Central America.

This paper reports a diagnostic inquiry on the human rights situation of persons with mental disorders in four Central American countries. The study was conducted by teams constituted of mental health workers and human rights lawyers, using a standard questionnaire prepared by the World Health Organization (WHO) and adapted for regional purposes by the America-based WHO office. The inquiry identified violations in different areas, e.g., involuntary admissions, informed consent and others. In general, violations were not associated with the level of social development of the country but with the affiliation of the care-giving system (private vs. public). This study will be followed by activities aimed at improving the current situation. [ABSTRACT FROM AUTHOR]

BACKGROUND: Pycnoderes quadrimaculatus is a pest that feeds on several plants, many of which are economically important. It is native to North/Central America and its distribution has expanded to several countries in South America. RESULTS: Ecological niche models show that P. quadrimaculatus has invaded regions with climates different from those of its native range, and that there are suitable climatic conditions for its establishment worldwide. Regions where P. quadrimaculatus is a major threat and possible natural pathways of ingression were identified. In the future, its distribution will be modified by climate change. CONCLUSIONS: This study provides useful information for risk assessment and pest management of P. quadrimaculatus. According to our results, the species has great potential as a pest because it can adapt to different climatic conditions and feeds on a wide range of economically important plants. Over time, its distribution has expanded, and our models suggest that it will continue to invade other regions unless preventive measures are taken. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Although the multi‐model average compares well with observations, individually most of the latest climate models do not simulate a realistic size of the Indo‐Pacific Warm Pool in the present‐day climate. This study explores the implications of this warm pool size bias in climate models in Northern Hemisphere winter. The warm pool size bias in phase 6 of the Coupled Model Intercomparison Project models is related to the subtropical jet and precipitation distribution, both in the present‐day climate and in response to climate change, through extratropical Rossby wave trains and tropical circulation pathways. Based on these relationships, emergent constraints are developed to observationally constrain the future subtropical jet response over Asia and the Atlantic Ocean and precipitation response over North and Central America, which can help to reduce uncertainty in future projections of these features. Thus, accurate model simulation of the warm pool in the present‐day climate is important for future projections of the subtropical jet and precipitation. Plain Language Summary: This study examines the impact of a common problem in the latest climate models where they do not accurately simulate the size of the Indo‐Pacific Warm Pool in the present‐day climate. The effects of this issue are investigated in the Northern Hemisphere winter. The warm pool size problem in the models affects the subtropical winds and precipitation, both in the current climate and in response to climate change. Based on the relationships between the present‐day warm pool size and future projections of the subtropical winds and precipitation across models, we can help to constrain future projections of the subtropical winds over Asia and precipitation over North and Central America by ruling out models with biased warm pool size. The results show that having an accurate simulation of the warm pool in the present‐day climate is crucial for more reliable future projections of subtropical winds and precipitation. Key Points: Phase 6 of the Coupled Model Intercomparison Project multi‐model‐mean reproduces the observed Indo‐Pacific warm pool size well, but there is a huge inter‐model spread in warm pool sizeModel biases in warm pool size have local and remote effects on subtropical winds and precipitation in present‐day and future climatesEmergent constraints reduce projection uncertainty of subtropical winds and precipitation by ruling out models with biased warm pool size [ABSTRACT FROM AUTHOR]

High‐quality records of hydroclimate variability in central Mexico during the last 2000 years are necessary to better understand human–environment interactions in Mesoamerica. Of particular interest are the climatic conditions during the Epiclassic period (ad 600–900), as droughts have been associated with a cultural demise occurring around ad 900–1000. We reconstruct the hydroclimate history of the last 2000 years based on a sediment record from a drought‐sensitive lake located near one of the most important Epiclassic city‐states in Mesoamerica. Titanium concentrations, pollen and diatoms give a consistent environmental signal of five droughts occurring at about: (i) ad 50–250, (ii) ad 700–950, (iii) ad 1200–1300, (iv) ad 1450–1550 and (v) ad 1760–1820. Some droughts were associated with cooler climatic conditions, and all of them framed major historical events. Our results show that the great cultural development of the Epiclassic period (ad 600–900) was framed by a scenario of drought conditions followed by abandonment at ad 900–1000. A brief return to moister conditions is recorded before another drought during the time of the fall of the city‐state of Tula (1200). European contact (1521) and the War of Independence (1810–20) also occurred during times of drought. [ABSTRACT FROM AUTHOR]

This paper presents the results of an exploratory study describing a group of Central American insurers in their beginning efforts using the management tool of strategic planning. The unique characteristics of the Central American environment and their effect upon strategic planning are explored and analyzed. This analysis leads to a set of recommendations for those corporate executives and academicians concerned with insurance and reinsurance companies in Central America. [ABSTRACT FROM AUTHOR]

Aim: Tropical forest succession and associated changes in community composition are driven by species demographic rates, but how demographic strategies shift during succession remains unclear. Our goal was to identify generalities in demographic trade‐offs and successional shifts in demographic strategies across Neotropical forests that cover a large rainfall gradient and to test whether the current conceptual model of tropical forest succession applies to wet and dry forests. Location: Mexico and Central America. Time period: 1985–2018. Major taxa studied: Trees. Methods: We used repeated forest inventory data from two wet and two dry forests to quantify demographic rates of 781 tree species. For each forest, we explored the main demographic trade‐offs and assigned tree species to five demographic groups by performing a weighted principal components analysis to account for differences in sample size. We aggregated the basal area and abundance across demographic groups to identify successional shifts in demographic strategies over the entire successional gradient from very young (<5 years) to old‐growth forests. Results: Across all forests, we found two demographic trade‐offs, namely the growth–survival trade‐off and the stature–recruitment trade‐off, enabling the data‐driven assignment of species to five demographic strategies. Fast species dominated early in succession and were then replaced by long‐lived pioneers in three forests. Intermediate and slow species increased in basal area over succession in all forests, but, in contrast to the current conceptual model, long‐lived pioneers continued to dominate until the old‐growth stage in all forests. The basal area of short‐lived breeders was low across all successional stages. Main conclusions: The current conceptual model of Neotropical forest succession should be revised to incorporate the dominance of long‐lived pioneers in late‐successional and old‐growth forests. Moreover, the definition of consistent demographic strategies that show clear dominance shifts across succession substantially improves the mechanistic understanding and predictability of Neotropical forest succession. [ABSTRACT FROM AUTHOR]

The role of the philanthropic sector in climate change mitigation and biodiversity conservation is gaining renewed attention as new pledges to dramatically increase funding for nature‐based climate solutions mount. Despite their significant role in the conservation space, philanthropies are relatively understudied as donors; in particular, the lack of accountability and transparency in philanthropy have made them a "black box", including in conservation‐related efforts. Based on extensive document and database review alongside interviews with philanthropic grant‐makers and recipients, this article seeks to analyze the conservation‐related efforts of the Ford Foundation—a long‐standing philanthropic actor in international sustainable development. Specifically, we examine how Ford Foundation practices in Mexico and Central America have shifted since 2000 to center Indigenous Peoples and local communities, both in terms of thematic focus and strategic approach. In explaining how Ford Foundation grant‐makers themselves understand the process of change, and their lessons from this process, this article highlights the ongoing challenges to and possible methods for centering inclusive, territorial approaches to produce more effective, lasting conservation outcomes. [ABSTRACT FROM AUTHOR]

The SPLASH project (2004–2006) revealed complex population structure and migratory connections, but no regional effort was made along the southern Mexican Pacific coast until dedicated research was initiated in 2010. It is unclear whether humpback whales documented in this region belong to the Mexican or Central American population units. This study aimed to establish the relationship between humpback whales of southern Mexico and those of the surrounding population units. Humpback whale photo‐identification images were compared from multiple locations in north, central, and southern Mexico and Central America. Whales' movements among regions were estimated using the Interchange Index (InI) and the Movement Index (MI). The results showed higher movements among the southern sampling areas, suggesting that whales from southern Mexico belong to the "Central American population unit." This population unit migrates north to the feeding areas of the US West Coast using a migratory corridor along mainland Mexico to the mouth of the Gulf of California along the Baja California Peninsula. The degree of interaction with humpback whales from other population units is unknown. More studies are needed to understand population structure and disentangle photographic capture of whales on migration from whales where this is their main wintering area. [ABSTRACT FROM AUTHOR]

Climate envelope models have been used to evaluate the predicted impacts of climate change on species of concern and can be a useful planning tool in determining the long‐term suitability of current habitat and potential introduction sites. However, due to model complexity, these models have generally been seen as "black boxes" when it comes to understanding why they make the predictions they do. In this study, we examined current potential ocelot (Leopardus pardalis) habitat using publicly available ocelot records and CHELSA bioclimatic variables combined in an ensemble model approach. We then predicted future potential ocelot habitat under three different emission scenarios using five climate models produced at a 30 arcsec grid cell size. To better understand what was driving model predictions, we used a variety of model interpretability approaches, including variable importance values, Shapley additive explanations, interaction detection, and a local surrogate model. These approaches revealed that ocelot potential habitat was associated with at least 233 mm of precipitation during the warmest quarter (BIO18) and at least 146 mm of precipitation during the wettest month (BIO13). Shapley additive explanations, applied to four protected areas across the species range, were valuable for understanding which climatic predictors drove predicted ocelot habitat at a local scale, with the protected areas with the highest predicted values having consistently more precipitation and higher temperatures. These tools are model agnostic and can be used to assess model predictions for biological validity and to further understand potential underlying relationships. As climate change shifts species range distributions, species distribution models and the tools to interpret them may become increasingly valuable, particularly on the leading edge of range expansion. [ABSTRACT FROM AUTHOR]

Seasonal rainfall forecasts provide information several months ahead to support decision making. These forecasts may use dynamic, statistical, or hybrid approaches, but their comparative value is not well understood over Central America. This study conducts a regional evaluation of seasonal rainfall forecasts focusing on two of the leading dynamic climate ensembles: the Copernicus Climate Change Service seasonal forecasting system (C3S) and the North American Multimodel Ensemble (NMME). We compare the multimodel ensemble mean and individual model predictions of seasonal rainfall over key wet season periods in Central America to better understand their relative forecast skill at the seasonal scale. Three types of rainfall forecasts are compared: direct dynamic rainfall predictions from the C3S and NMME ensembles, a statistical approach using the lagged observed sea surface temperature (SST), and an indirect hybrid approach, driving a statistical model with dynamic ensemble SST predictions. Results show that C3S and NMME exhibit similar regional variability with strong performance in the northern Pacific part of Central America and weaker skill primarily in eastern Nicaragua. In the northern Pacific part of the region, the models have high skill across the wet season. Indirect forecasts can outperform the direct rainfall forecasts in specific cases where the direct forecasts have lower predictive power (e.g., eastern Nicaragua during the early wet season). The indirect skill generally reflects the strength of SST associations with rainfall. The indirect forecasts based on Tropical North Atlantic SSTs are best in the early wet season and the indirect forecasts based on Niño3.4 SSTs are best in the late wet season when each SST zone has a stronger association with rainfall. Statistical predictions are competitive with the indirect and direct forecasts in multiple cases, especially in the late wet season, demonstrating how a variety of forecasting approaches can enhance seasonal forecasting. [ABSTRACT FROM AUTHOR]

Biogeographic disjunction patterns, where multiple taxa are shared between isolated geographic areas, represent excellent systems for investigating the historical assembly of modern biotas and fundamental biological processes such as speciation, diversification, niche evolution, and evolutionary responses to climate change. Studies on plant genera disjunct across the northern hemisphere, particularly between eastern North America (ENA) and eastern Asia (EAS), have yielded tremendous insight on the geologic history and assembly of rich temperate floras. However, one of the most prevalent disjunction patterns involving ENA forests has been largely overlooked: that of taxa disjunct between ENA and cloud forests of Mesoamerica (MAM), with examples including Acer saccharum, Liquidambar styraciflua, Cercis canadensis, Fagus grandifolia, and Epifagus virginiana. Despite the remarkable nature of this disjunction pattern, which has been recognized for over 75 years, there have been few recent efforts to empirically examine its evolutionary and ecological origins. Here I synthesize previous systematic, paleobotanical, phylogenetic, and phylogeographic studies to establish what is known about this disjunction pattern to provide a roadmap for future research. I argue that this disjunction pattern, and the evolution and fossil record of the Mexican flora more broadly, represents a key missing piece in the broader puzzle of northern hemisphere biogeography. I also suggest that the ENA–MAM disjunction represents an excellent system for examining fundamental questions about how traits and life history strategies mediate plant evolutionary responses to climate change and for predicting how broadleaf temperate forests will respond to the ongoing climatic pressures of the Anthropocene. [ABSTRACT FROM AUTHOR]

Total electron content (TEC) and L‐band scintillations measured by several networks of GPS and GNSS receivers that operate in South and Central America and the Caribbean region are used to observe the morphology of the equatorial ionization anomaly (EIA), examine the evolution of plasma bubbles, and investigate the enhancement of L‐band scintillations that occurred on February 12 and 13, 2016. A few weak and short magnetic storms developed these days, and a minor sudden stratospheric warming (SSW) event was initiated a few days before. During these unusual conditions, TEC maps reported a split of the otherwise continuous crests of the EIA and the formation of a large‐scale (thousands of kilometers) almost‐circular structure. The western part of the southern crest faded, and a north‐south aligned segment developed near the center of the South American continent, joining the north and south crests of the EIA, forming an anomaly that resembled a closed loop on the eastern side of the continent. Concurrently with the anomaly events, several GPS stations reported increases in the L‐band scintillation index from 0.4 to values greater than 1. We analyzed TEC values from receivers between ±6° from the magnetic equator to identify and follow TEC depletions associated with plasma bubbles when they reach different stations. Although the magnetic activity was moderate (Kp = 3°), we believe that the anomaly redistribution and the scintillation enhancements are not related to a prompt penetration electric field but to enhancing the semidiurnal lunar tide propitiated by the onset of the minor SSW event. We found that depending on the lunar tide phase cycle, the neutral wind's meridional component can augment sub‐km scale irregularities and enhance L‐band scintillations through the wind gradient instability when U·∇ $\nabla $n < 0 or the action of wind gradients (∇ $\nabla $U) within the bubbles. Our observations imply that the SSW event enables prominent changes in the thermosphere wind system at F‐region altitudes. Plain Language Summary: GPS receivers can measure the total electron content (TEC) between the satellite and the ground receivers. We have used TEC data collected with several networks of GPS receivers in South America to construct maps of TEC over the continent. These maps are used to examine the variability of the low latitude ionosphere during a special event that originates in the northern polar stratosphere called sudden stratospheric warming (SSW), consisting of an increase in the local temperature. In February 2016, a minor SSW produced prominent changes in the equatorial ionization anomaly. The anomaly consists of a pattern of two regions of enhanced densities on both sides of the magnetic equator that develops during the daytime and early evening. A few days after the initiation of the SSW event, the low‐latitude ionosphere dynamics changed, forming a large‐scale structure resembling a closed loop on the continent's eastern side. Concurrently with the anomaly events, several GPS stations reported increases in the level of fadings of the GPS signal‐to‐noise ratio, a process called scintillation. It is indicated that the neutral wind meridional component developed shears and a reversal increasing the level of plasma irregularities at km and sub‐km‐scale lengths, originating a scintillation enhancement. Key Points: Sudden increases in L‐band scintillations coincide with changes in the geometry of the equatorial ionization anomalyThese events occurred on February 12 and 13, 2016, a few days after a minor sudden stratospheric warming eventThe analysis suggests that a meridional neutral wind associated with an increased lunar tide is responsible for anomaly variability [ABSTRACT FROM AUTHOR]

The Regional Atmospheric Modelling System (RAMS) driven by data from the CMIP5 Earth System Model HadGEM2‐ES was used to simulate daily precipitation over the tropical Americas for both current and future climate, including distinct scenarios (representative concentration pathways 4.5 and 8.5) and different time horizons (short‐term, mid‐term and long‐term changes). The major objective was to evaluate possible future changes in extreme events, with emphasis on the intensity of precipitation events and the duration of wet and dry spells. According to RAMS, longer dry spells are expected over most regions of the tropical Americas in the future, with indications for Northeast Brazil, Caribbean, Northern Amazon, and shorter wet spells over Central America and Amazon. With the exception of the Caribbean, there is a general tendency towards the increased frequency of intense precipitation in the tropical Americas. [ABSTRACT FROM AUTHOR]

Rainfall mechanisms in the Central American Isthmus are controlled by complex physical interactions across spatial and temporal scales, which are reflected on the dynamics of atmospheric circulation patterns affecting the region. However, physical mechanisms and their relationships with thermodynamic distributions connected to overturning circulations remain elusive. Here, a set of six recurrent daily atmospheric patterns, or weather types (WT), is defined using a k‐means++ clustering algorithm on standardized fields of Convective Available Potential Energy (CAPE) and winds at 925, 850, and 200 hPa. The relationships between these weather types, their temporal characteristics, and anomalous distributions of moisture flux divergence, equivalent potential temperature (saturated and unsaturated), and observed rainfall are used to describe physical processes controlling the latter, for all seasons. Regional observed rainfall is analysed from a set of 174 automatic stations from all countries from Mexico to Panama. By modulating vertically integrated moisture fluxes, these weather types, and the different climate drivers linked to them, control the temporal and spatial rainfall characteristics in the region, especially over the Pacific side of the isthmus. During some stages of the regional rainy season, described by two weather types, thermal anomalies in convective quasi‐equilibrium characteristic of the upward branch of the Hadley cell force westerly flow over Central America, enhancing rainfall. While during other stages, the enhancement of the trades and the displacement of convection to the ITCZ area over the eastern tropical Pacific, characteristic of the midsummer drought, diminishes rainfall. This study sets the stage for a better understanding of the mechanistic relationship between these weather types and rainfall characteristics in general, like onset, demise, and duration of rainy seasons. Hence, these results can inform process‐based model diagnostics aiming at bias‐correcting climate predictions at multiple timescales. [ABSTRACT FROM AUTHOR]

We analyse the effects of deforestation and the projected differential sea surface temperature (SST) anomalies between the tropical North Atlantic and the eastern North Pacific on the mid‐summer drought (MSD) over southern Mexico and Central America. To address these issues, we performed a set of three 6‐year (1996–2001) sensitivity experiments with RegCM4 driven by the ERA‐Interim reanalysis and employing different SST (projected end of century patterns under the RCP8.5 scenario) and vegetation (turning forest landuse into grass) configurations. The model domain follows the specifications of the COrdinated Regional Downscaling EXperiment (CORDEX) for Central America. Results indicate that projected SST patterns cause the MSD signal to almost disappear from the regional mean annual cycle, with its spatial extent decreasing from ~82 to ~48%. In the vegetation sensitivity experiment, the MSD intensity increases along the Pacific coast and Central America, while the MSD spatial extent remains almost unchanged. These regional changes in MSD can be explained in terms of the regional precipitation response to deforestation, primarily due to changes in vertical moisture advection. [ABSTRACT FROM AUTHOR]

Palms (Arecaceae) represent a challenge for studies of morphological variation for several various reasons. For instance, the height of many species makes them difficult to collect, and in some cases, the size of the leaves or the presence of spines make them hard to process and preserve in herbaria. Arecaceae is one of the most diverse families of monocots (ca 2600 species), and many of its species remain poorly studied. The genus Gaussia has five recognized species. Their distributions are restricted to Central America and the Caribbean islands, and for most of them, their taxonomic descriptions are the only information available. Two species – Gaussia maya and G. gomez‐pompae – are exclusively distributed in Mesoamerica. They occur allopatrically and their populations are isolated from each other. The aim of this work was to evaluate the levels of intra‐ and inter‐population morphological variation in both species and determine the possible factors that influence such a variation. We examined the morphological variation of 13 vegetative structures of 155 adult individuals from nine populations of G. maya and G. gomez‐pompae. The differentiation among populations was significant for almost all the variables and was consistent with an isolation‐by‐distance pattern. A linear discriminant analysis, Mahalanobis distances and UPGMA cluster analysis based on Euclidean distances among populations showed that three morphological groups could be distinguished. One group contained only individuals of G. maya, the second only G. gomez‐pompae, while the third group represents a yet unknown taxon. Pairwise differentiation tests clarified the morphological distinction among the three groups. This work highlights the importance of quantifying morphological variation between populations of little‐studied palms. [ABSTRACT FROM AUTHOR]

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Aim: The biodiversity crisis has highlighted the need to assess and map biodiversity in order to prioritize conservation efforts. Clearwing butterflies (tribe Ithomiini) have been proposed as biological indicators for habitat quality in Neotropical forests, which contain the world's richest biological communities. Here, we provide maps of different facets of Ithomiini diversity across the Neotropics to identify areas of evolutionary and ecological importance for conservation and evaluate their overlap with current anthropogenic threats. Location: Neotropics. Methods: We ran species distribution models on a data set based on 28,986 georeferenced occurrences representing 388 ithomiine species to generate maps of geographic rarity, taxonomic, phylogenetic and Müllerian mimetic wing pattern diversity. We quantified and mapped the overlap of diversity hotspots with areas threatened by or providing refuge from current anthropogenic pressures. Results: The eastern slopes of the Andes formed the primary hotspot of taxonomic, phylogenetic and mimetic diversity, with secondary hotspots in Central America and the Atlantic Forest. Most diversity indices were strongly spatially correlated. Nevertheless, species‐poor communities on the Pacific slopes of the Andes also sheltered some of the geographically rarest species. Overall, tropical montane forests that host high species and mimetic diversity as well as rare species and mimicry rings appeared particularly under threat. Main conclusions: Remote parts of the Upper Amazon may act as refuges against current anthropogenic pressures for a limited portion of Ithomiini diversity. Furthermore, it is likely that the current threat status may worsen with ongoing climate change and deforestation. In this context, the tropical Andes occupy a crucial position as the primary hotspot for multiple facets of biodiversity for ithomiine butterflies, as they do for angiosperms, tetrapods and other insect taxa. Our results support the role of ithomiine butterflies as a suitable flagship indicator group for Neotropical butterfly diversity and reinforce the position of the tropical Andes as a flagship region for biodiversity conservation in general, and insect and butterfly conservation in particular. [ABSTRACT FROM AUTHOR]

This research investigates the effect of well‐being indicators and social globalization on the migration of Unaccompanied Alien Children (UAC) from Central America. The purpose of this study is to determine whether the surge in UAC that began in 2014 at the U.S. southern border is driven primarily by violence or whether other factors are at play. The apprehension of UAC serves as a proxy for measuring unaccompanied child migration to the United States. Unemployment rates of young adults and expected years of schooling are included as a measure of youth engagement in productive activities, while homicide rates measure the threat to leading a productive, healthy life. Global social network links are considered as possible pull factors of migration and measured through a social globalization index. The results of a fixed effects regression model reveal that youth idleness, along with increased social globalization, prove to be significant in explaining heightened UAC migration. [ABSTRACT FROM AUTHOR]