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The main source of electricity in Brazil is from hydro, which has about 65.2% share of the country’s electric energy matrix. However, over the last decade the wind energy increased from 19 MW to 2.2 GW. Since wind is an intermittent energy source, heavily determined by the weather and climatic conditions, and important effects on wind power generation can be expected in the mid and long term, in particular related to the impacts of extreme winds. The IPCC AR5 (Intergovernmental Panel on Climate Change) indicates changes in wind speed at the surface in some regions of the world, and increased wind strength in mid-latitude regions. This study scrutinizes future scenarios of extreme winds in Brazil by applying trend analysis techniques on a 50-year historical series of observational wind speed and meteorological parameters at 10 m height in Brazil. Embracing techniques of cluster analysis it was possible to characterize six main regions with macro climatic similarities. To assess the goodness fit distribution, we designate two stations per homogenous region, taking as criteria the stations with better performance in the qualification process to determine the wind distribution pattern in each region applying the Kolmogorov-Smirnov test (KS) and the lowest standard error (SE). After evaluating the frequency distribution of wind speed, the best fit result for the frequency distribution of maximum wind speed is the Gumbel model. The analysis of climatic trends performed by Mann-Kendall test revealed that in minimum wind speed series is not conclusive because it shows disparate results between homogeneous regions. On the other hand, the analysis of climatic trends of maximum wind speed presents 100% positive trends in Group#1, an equal number of stations with not significant trends and positive trends for Group#2, 36.8% more stations with positive trends than negative trends for Group#3 and 20% of stations with more negative trends than stations with positive trends for Group#4. This way, based in these results, is possible assert that there are an increase in the maximum extreme wind in Brazil, mainly in mid-latitudes.

O presente trabalho tem como objetivo apresentar um estudo sobre a variabilidade hidrológica em uma microbacia instrumentada, localizada na Floresta Amazônica, próximo a cidade de Manaus. Foram utilizados dados de precipitação, umidade do solo, nível de lençol freático e vazões, correspondentes a alguns períodos entre os anos de 2006 a 2016. Esses dados tiveram que passar por etapas de formatação e qualificação, através da criação de gráficos. Dessa forma, tornou-se possível identificar melhor os períodos que necessitavam de alguma correção realizando uma análise sobre esses possíveis erros encontrados. Com o estudo destes dados e dos demais estudados, contribui-se para uma melhor análise sobre o comportamento hidrológico da microbacia. As series apresentam uma importante variabilidade intra e interanual na resposta hidrológica da bacia, associada com a variabilidade climática.

As transformações da cobertura vegetal no Vale do Paraíba do Sul fluminense resultaram de um processo histórico de mudanças de uso. Atualmente a sociedade fluminense observa após um intenso conflito para a liberação da produção da silvicultura em escala comercial um crescimento da área plantada em algumas regiões. Por isso, esse trabalho visa através de uma análise espaço-temporal analisar a dinâmica de expansão da cultura de eucaliptos e sua disseminação nessa região entre os anos de 2010 e 2015. Inicialmente foi obtida as imagens Landsat 5, ortorretificada (órbita/ponto 218/076).Apos adquiridas as imagens foram classificadas e remapeadas para em seguida ser obtido o mapa de uso e ocupação do solo. Para reconhecer as mudanças no mosaico da paisagem na zona de fronteira de expansão do eucalipto assim como analisar o posicionamento dos plantios no contexto da paisagem do Vale do Paraíba Fluminense, foi gerado mapa de uso e cobertura do solo. Este mapeamento foi realizado em dois recortes temporais 2010 e 2015. O método de mapeamento utilizado foi o de classificação digital de imagens de satélite. Para o ano 2010, foi utilizada uma imagem O processo de classificação foi realizado pelo software ArcGIS (versão 10.2), sendo realizada a distinção de seis categorias: agricultura, área urbana, corpo hídrico, pastagem, silvicultura de eucalipto e vegetação. Foi constatado no oeste do vale do paraíba fluminense a prevalência de uma cobertura de gramíneas com pastagem concentrados, principalmente, no domínio montanhoso, enquanto a área urbana apresenta-se pouco expressiva.

The epidemiological risk several times come from the relationship between human and the environment. In a endemic region of malaria such as Amazon, the different ways of using and organizing the environment imply in different levels of human exposure to the vector. Thus, the landscape can be used as an indication,of the presence of vectors and the hosts of malaria due to the association of them with some types of land cover and their spatial arrangements. The main objective of this study is to generate a gradient map of human exposure to malaria vector based on the landscape analysis, using TerraClass 2010 data, represented by cells of 16 km2 in the Manaus municipality (AM). The landscape in this work is considerate as a mediator element for the determination and spatialization of human exposure levels to malaria vector. The gradient map resultant of the analysis was compared with the malaria infection data from SIVEP-Malaria 2010, also represented by cells map. The results showed good adherence between the exposure map and the malaria infection data, indicating that landscape is a promising mediator for generation and spacialization of human exposure levels to the malaria vector.

The Chilean arid, semi-arid and sub-humid zone presents serious problems associated with desertification processes. The region is characterized by a precipitation concentrated in a few months, with long dry periods during the year, and a high climatic variability, associated mainly to the “El Niño, Southern Oscillation” phenomenon 3 . Due to this variability, there are very dry and wet years, favoring the water erosion in the area. In addition, the region has been historically over exploited by different human activities, such as mining, agriculture and livestock. In northern and central Chile, the climate may have different roles in accelerating desertification. First by the tendency to decreasing rainfall during the 20th century and in the early 21st century, second by the increase in rainfall variability and the intensity, increasing its erosive effect.. Besides this, climate projections indicate a more aggressive climate in the future, contributing to the soils and ecosystems degradation 6 . The main objective of this work is to seek a better understanding of the desertification processes associated with pasture in different dry regions of Chile, and to investigate possible changes in these mechanisms under future climate projections.

This study provides an overview of the drought situation in Northeast Brazil for the past, present, and future. Droughts affect more people than any other natural hazard owing to their large scale and long-lasting nature. They are recurrent in the region and while some measures have been taken by the governments to mitigate their impacts, there is still a perception that residents, mainly in rural areas, are not yet adapted to these hazards. The drought affecting the Northeast from 2012 to 2015, however, has had an intensity and impact not seen in several decades and has already destroyed large swaths of cropland, affecting hundreds of cities and towns across the region, and leaving ranchers struggling to feed and water cattle. Future climate projections for the area show large temperature increases and rainfall reductions, which, together with a tendency for longer periods with consecutive dry days, suggest the occurrence of more frequent/intense dry spells and droughts and a tendency toward aridification in the region. All these conditions lead to an increase in evaporation from reservoirs and lakes, affecting irrigation and agriculture as well as key water uses including hydropower and industry, and thus, the welfare of the residents. Integrating drought monitoring and seasonal forecasting provides efficient means of assessing impacts of climate variability and change, identifying vulnerabilities, and allowing for better adaptation measures not only for medium- and long-term climate change but also for extremes of the interannual climate variability, particularly droughts.

Aim Conservationists have been using ecological niche modelling (ENM) to understand how climate change impacts species, estimate their extinction risk and assess species conservation status in the future. However, most ENMs are built using just current species occurrences. As short-term observations are naturally biased and incomplete in both geographical and climate spaces, palaeontologists have recommended the use of fossil data to improve species vulnerability assessments. Here, we used a time structured data set of the jaguar Panthera onca (Linnaeus, 1758) to test the implications of fossil data on distinct distribution dynamics and conservation status predicted by ENMs under future climate change scenarios. LocationThe New World. MethodsWe built two classes of ENMs, (i) using only current occurrences of P.onca and (ii) combining current and fossil information. Models were then projected onto current and future climates. ResultsNiche models calibrated using fossil data broadly predicted more optimistic conservation statuses, with larger suitable areas for the species in the future, which are geographically nearest to its current distribution and better represented within protected areas (current network of protected areas will hold significant suitable areas). Main conclusionsFossils provided complementary information about different climate conditions that species experienced though time and filled empty spaces in currently unoccupied fundamental niche. Our analyses reinforce the idea the fossil record is a valuable source of alternative information to increase the reliability of ENMs when assessing biodiversity risk. Combining ecological and palaeontological data for niche modelling increase our understanding about species responses to changing climates. Consequently, it potentially improves our knowledge on how to manage biodiversity by more reliably anticipating the effects of climate change and proactivelyrather than reactivelyplanning conservation actions over longer periods going forward.

AimTo propose and compare priority sites for conservation and restoration of woody plants under diverse climate and land use scenarios, considering socio-economic costs, presence of protected areas and distribution of forest remnants. LocationThe Atlantic Forest Biodiversity Hotspot, Brazil. MethodsWe used ecological niche modelling to estimate geographical distributions for 2,255 species under current and future climate scenarios, which we analysed in relation to spatially explicit land use projections, maps of forest remnants derived from remote sensing and socio-economic variables for each municipality within the Atlantic Forest region. We identified spatial priorities that complement the current network of protected areas under three different prioritization scenarios: (1) conservation of existing forest remnants only; (2) conservation of remnants followed by restoration of degraded habitat; and (3) unconstrained actions, in which management location is not defined a priori. We compared our results under different levels of land protection, with targets of 10%, 17% and 20% of the Atlantic Forest extent. ResultsCurrent forest remnants cover only 12% of the Atlantic Forest, so targets of 17% and 20% were achieved only through active restoration. Targets of 17% and 20% captured most species and represented on average 26%-34% of species’ distributions. The spatial pattern of degraded habitats negatively affected representation of biodiversity and implied higher costs and reduced efficiency of planning. We did not observe major differences between conservation prioritizations based on contrasting climate change scenarios. Main conclusionsProtection of forest remnants alone will not suffice to safeguard woody plant species under climate and land use changes; therefore, restoration actions are urgently needed in the Atlantic Forest. With integrated management actions and multicriterion nationwide planning, reaching the 17% of land protection of Aichi biodiversity targets will constitute an important step towards protecting Atlantic Forest biodiversity.

O presente estudo objetiva determinar Regiões homogêneas do SPI-6 na Amazônia Oriental e analisar as principais características dos eventos secos e chuvosos em cada região. Para o cálculo do SPI, utilizou-se dados de precipitação de 72 postos pluviométricos distribuídos na Amazônia Oriental. Além disso, aplicou-se o Agrupamento Hierárquico de Ward para determinar as Regiões Homogêneas e a Análise Fatorial em Componentes Principais (ACP) para determinar os principais padrões de variabilidade climáticas associados aos eventos secos e chuvosos. Os resultados obtidos pela Análise de Agrupamento mostraram a existência de três Regiões Homogêneas em relação ao SPI-6: RH-1 (litoral), RH-2 (central) e RH-3 (sul). De modo geral a região do litoral apresentou mais eventos secos que chuvosos. Nas demais regiões (central e sul) a situação é inversa, isto é, existem mais eventos de chuva, porém com pouca duração. Por meio da ACP verificou-se que os eventos secos e chuvosos na Amazônia Oriental estavam associados, principalmente, a variabilidade climática dos oceanos Atlântico (Gradiente do Atlântico) e Pacífico (ENOS).

The physical mechanism of lightning attachment to grounded structures is one of the most important issues in lightning physics research, and it is the basis for the design of the lightning protection systems. Most of what is known about the attachment process comes from leader propagation models that are mostly based on laboratory observations of long electrical discharges or from observations of lightning attachment to tall structures. In this paper we use high-speed videos to analyze the attachment process of downward lightning flashes to an ordinary residential building. For the first time, we present characteristics of the attachment process to common structures that are present in almost every city (in this case, two buildings under 60 m in São Paulo City, Brazil). Parameters like striking distance and connecting leaders speed, largely used in lightning attachment models and in lightning protection standards, are revealed in this work.

A previsão de níveis de rios é um elemento importante de um sistema de alertas de desastres associados com eventos hidrológicos extremos. Neste trabalho é apresentado o uso de previsões de tempo de curto e médio prazo e de previsões climáticas sazonais por conjunto para monitoramento de cheias extremas em grandes bacias hidrográfi cas. Os resultados do estudo de caso da cheia no Rio Madeira em Porto Velho no ano hidrológico 2013-2104, que teve seu pico em 30 de março de 2014, apresentam um bom desempenho do acoplamento entre o modelo atmosférico Eta-INPE e o modelo hidrológico MHD-INPE para as previsões de vazões. As análises sugerem que as previsões sazonais podem ser utilizadas para indicar a potencial ocorrência de um evento acima dos limiares de alerta e de emergência, enquanto que as previsões de tempo auxiliam na estimativa dos valores extremos uma vez estabelecida a onda de cheia. Este tipo de utilização conjunta de previsões em diferentes escalas permite focalizar com maior antecedência as regiões de impacto potencial.

Atualmente a energia eólica está mostrando destaque no cenário energético brasileiro por ser uma fonte energética renovável que apresenta elevada disponibilidade no território e cujo aproveitamento baixos níveis de emissão de gases de efeito estufa. Em razão desses aspectos, a energia eólica é uma promissora alternativa para ajudar a reverter o quadro atual de crise energética decorrente da escassez do recurso hídrico e o crescimento da emissão de gases de efeito estufa decorrente do crescimento da participação de combustíveis fósseis na matriz elétrica brasileira. Na perspectiva econômica, a geração eólica está apresentando custos competitivos com as fontes convencionais de energia. Entretanto, como qualquer outra atividade econômica, pode causar impactos sociais e ambientais que devem ser analisados e mitigados. Essas dimensões controversas da energia eólica tornam a questão da localização de parques eólicos um problema bastante complexo, dado a incompatibilidade entre esses impactos de caráter localizado e o grande benefício público associado à segurança energética do país. Este artigo apresenta uma revisão dos estudos e publicações sobre o aproveitamento eólico no Brasil com o intuito de promover uma discussão sobre aspectos relacionados aos impactos socioambientais. Em razão da curta história do aproveitamento eólico no Brasil, estudos para avaliação mais aprofundada dos impactos socioambientais devem ser realizados com apoio de recursos do próprio setor energético a fim de promover um crescimento sustentável da participação desta fonte energética na matriz elétrica nacional.