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In this report monthly thunderstorm days (TD) in 14 large cities of Brazil from 1951 to 2010 are compared with data obtained in the first part of the 20th century in the same cities and correlated with sea surface temperature (SST) of the equatorial Pacific Ocean and Tropical Atlantic Ocean. On average over all cities, 77 TD are reported each year after 1951, against 43 TD in the first part of the 20th century, an increase of 79%. The increase seems to be related to increase in the urbanization in these cities, and not to global warming. A comparative analysis of TD for the whole country with El Niño-Southern Oscillation (ENSO) events suggests that the tendency for El Niño to increase the thunderstorm activity is evident in the South (only in the Spring/Summer), Southeast, Northeast and North (only in the Fall/Winter) regions. Regarding the Tropical Atlantic Ocean SST, a similar analysis using the Tropical South Atlantic (TSA) and Tropical North Atlantic (TNA) indices suggests that no significant differences exist between the thunderstorm activity for the two extreme positive and negative TSA conditions in the South and Southeast regions, while in the Northeast and North regions there is a significant increase in the thunderstorm activity during extreme positive TSA. Differently, only in the Northeast region there is a significant influence of TNA on thunderstorm activity. The influence is such that the thunderstorm activity is larger for the extreme negative TNA than for extreme positive TNA. All significant changes were quantified and significant variations were observed. For all parameters investigated (ENSO, TSA and TNA) the Northeast region showed the most significant changes.

Environmental scenarios were largely exploratory in the past decades. Normative approaches gradually became more popular and more widely applied over the last decade, due to the rising popularity of the strongly normative concept of sustainability. Here we present a normative scenario approach conceived to promote the discussion about a sustainable future in heterogeneous and conflicting regions such as the Brazilian Amazon. We present a synthesis of the scenario process and the two case studies. The first case study was developed on an agro-extrativist settlement project. Then, we successfully reproduced the method to the whole Brazilian Amazon, involving representatives of civil society organizations, productive sector and government. The normative scenario approach we adopted here was conceived as a tool to subsidize a broader discussion about the future we want and how to get there – acknowledging that current society decisions will strongly influence the future.

The study aims to analyze the spectral behavior of leaves of Eucalyptus globulus attacked in four different severity levels by Mycosphaerella spp. in different positions in the canopy of the tree in the four seasons, considering two regions of the electromagnetic spectrum: visible and near infrared. The plant material was collected in all seasons, in different positions in the tree (base, middle and top of the canopy extract). In the laboratory, leaves were classified into four levels of severity (healthy, little, medium and heavy fire) and then made measurements of spectral reflectance measured with a spectroradiometer. The spectral behavior of Eucalyptus globules leaves is characteristic according to the severity degree of the disease, differing primarily in the other high levels of infection by Mycosphaerella spp. and differ mainly of healthy leaves and leaves which are little attacked, in both regions of the electromagnetic spectrum, this behavior occurs for different treetop positions and climate seasons, varying the amount of reflected energy. It is concluded that the reflectance of the Eucalyptus globules leaves attacked by Mycosphaerella spp. differs according to the position in the tree crown and the weather station when they were collected and to the advanced levels of disease severity.

The proliferation of digital cameras co-located with eddy covariance instrumentation provides new opportunities to better understand the relationship between canopy phenology and the seasonality of canopy photosynthesis. In this paper we analyze the abilities and limitations of canopy color metrics measured by digital repeat photography to track seasonal canopy development and photosynthesis, determine phenological transition dates, and estimate intra-annual and interannual variability in canopy photosynthesis. We used 59 site-years of camera imagery and net ecosystem exchange measurements from 17 towers spanning three plant functional types (deciduous broadleaf forest, evergreen needleleaf forest, and grassland/crops) to derive color indices and estimate gross primary productivity (GPP). GPP was strongly correlated with greenness derived from camera imagery in all three plant functional types. Specifically, the beginning of the photosynthetic period in deciduous broadleaf forest and grassland/crops and the end of the photosynthetic period in grassland/crops were both correlated with changes in greenness; changes in redness were correlated with the end of the photosynthetic period in deciduous broadleaf forest. However, it was not possible to accurately identify the beginning or ending of the photosynthetic period using camera greenness in evergreen needleleaf forest. At deciduous broadleaf sites, anomalies in integrated greenness and total GPP were significantly correlated up to 60 days after the mean onset date for the start of spring. More generally, results from this work demonstrate that digital repeat photography can be used to quantify both the duration of the photosynthetically active period as well as total GPP in deciduous broadleaf forest and grassland/crops, but that new and different approaches are required before comparable results can be achieved in evergreen needleleaf forest.

É com grande satisfação que a Rede Brasileira de Pesquisas sobre Mudanças Climáticas Globais (Rede CLIMA) apresenta seu 5º Relatório de Atividades referente ao período de janeiro de 2014 a dezembro de 2015. O relatório traz as principais ações e resultados alcançados pela Rede através de suas 15 Sub-Redes temáticas. Seu conteúdo descreve cada sub-rede de forma sucinta, trazendo seus principais destaques. O relatório traz, ainda, os avanços e resultados das pesquisas e demonstra o empenho e esforço conjunto dos coordenadores e pesquisadores na formação e capacitação de recursos humanos. Além disso, o relatório documenta a concretização dos objetivos da Rede Clima no tocante à disseminação do conhecimento, de informação e a busca de alternativas de adaptação e mitigação das mudanças climáticas globais.

The progress from the last four years in solar energy resource assessment for Chile is reported, including measurements from a ground station network spanning from two to three years of data, and satellite estimations from the recently developed Chile-SR model including two full years of data. The model introduces different procedures for the meteorological variables and the effective cloud cover computations that allow estimation of the global horizontal and diffuse irradiation on an hourly basis. Direct normal irradiation is computed by applying proper solar geometry corrections to the direct horizontal irradiation. The satellite estimation model was developed as an adaptation from Brazil-SR model, with an improved formulation for altitude-corrected atmospheric parameters, and a novel formulation for calculating effective cloud covers while at the same time detecting and differentiating it from snow covers and salt lakes. The model is validated by comparison with ground station data. The results indicate that there are high radiation levels throughout the country. In particular, northern Chile is endowed with one of the highest solar resources in the world.

Extreme rainfall events can be considered a natural manifestation of the environment in which they are embedded and foreknowledge about their future behavior is very important, especially for decision makers. In this context, we aimed to explore the future behavior of extreme rainfall intensity through numerical simulations with the ETA model. The model was forced with a scenario of high greenhouse gas emissions for the middle of the 21st Century as described for A1B emission scenario. We detailed the main changes in accumulated rainfall produced by heavy events, very heavy events and rare events over a broad area of South America with a focus on the tropical sector. The methodology applied here is capable of separating extreme events and establishing the quantity of rainfall yielded by them. We have found that in the near future (2041-2050) rare events will tend to increase over the Amazon basin, followed by reductions in heavy and very heavy events. Conversely, heavy, very heavy and rare events are expected to decline over northeast Brazil. Furthermore, increases were found for heavy, very heavy and rare events over southern Brazil.

Changing climatic conditions have led to a significant increase in the magnitude and frequency of extreme rainfall events in the Central Andes of South America. These events are spatially extensive and often result in substantial natural hazards for population, economy and ecology. Here we develop a general framework to predict extreme events by introducing the concept of network divergence on directed networks derived from a non-linear synchronization measure. We apply our method to real-time satellite-derived rainfall data and predict more than 60% (90% during El Nino conditions) of rainfall events above the 99th percentile in the Central Andes. In addition to the societal benefits of predicting natural hazards, our study reveals a linkage between polar and tropical regimes as the responsible mechanism: the interplay of northward migrating frontal systems and a low-level wind channel from the western Amazon to the subtropics.

This database created by Nathan Vogt during a post-doctoral position within Axis 1 of the Land Use in the Amazon Institutional Analysis and Modeling (LUA-IAM) project at the National Institute of Space Studies (INPE) of Brazil. The goal of this database is to allow the reconstruction of landscape changes in the Lower Tapajós from 1975 to 2010. It is also intended to be used with a the time-series of the territorial units and roads/trails for the Lower Tapajós between 1975 and 2010 included in this data set for analysis of how creation of different types of territorial units and expansion of the road network affect the landscape trajectories. This polygon shapefiles of territorial units contained in the data set are those created in this time period in the municipalities of Aveiro, Belterra, Juriti, Medicilândia, Placas, Prainha, Ruropolis, Santarem and Uruara. Using census data collected on the dates in the time-series collected by the Instituto Brasileiro de Geografia e Estatística (IBGE) it is possible to analyze the role of socio-economic and land-use changes in the landscape trajectories. It was intended to be used in intensive field studies coupled with ethnographies with key elder informants to reconstruct landscape histories. However, it may also be used for modeling purposes. The extent can be used to link to regional-level climate models of relation of hydrological and energy fluxes that are typically coarse scale to link to studies in individual territorial units, communities or landscapes. It contains polygon shapefiles of all territorial units created in the Lower Tapajós between 1975 and 2010, it contains Landsat satellite images for 1975, 1985, 1990, 1995, 2000, 2005 and 2010, and it contains line shapefiles of the roads and trails that existed during these same dates.

In this work it is described the analysis of a surface image set obtained at SALa Martinho da Serra RS, Brazil. The images taken from a surface imager, will be used to establish a criteria to define clcar sky anel clouds for validation of satellite images. The methoel used for that purpose is the BAYESIAN in two steps: supervised learning anel analysis. Superviseellearning will be done by statistics tools anel multivariate exploratory data analysis or EDA. Analysis is based on hierarchic priority anel multivariate statistics discrimination. By this way, pixel values present on images will be mapped into atmospheric patterns. Only patterns ielentifiable in visible spectrum anel defined by optical and atmospheric physics will be analyzed. Two other methods were also implemented to be compared with the presenteel methoel. Complementary to surface images it was obtaineel solar data of global elirect anel eliffuse radiation from a co-allocateel BSRN station. From these sensors it was calculated cloud coverage estimates from surface. To reduce the massive amount of data, they will be split in monthly reports. The current report elescribes the methods useel to calculate data and describes the results relative to January of 2005 with 1659 images.

Este relatório apresenta a metodologia de coleta de dados e a descrição inicial dos resultados obtidos no trabalho de campo com comunidades de terra firme na região do Distrito Florestal Sustentável da BR-163, sudoeste do Pará. Realizado no período de 06 a 26 de setembro de 2013, esse trabalho complementa e reproduz parcialmente os levantamentos de campo realizados nas comunidades ribeirinhas do Tapajós e Arapiuns em 2009 e 2012, respectivamente. A área de estudo apresenta diferentes tipos de ocupação e contextos como a presença de Unidades de Conservação, Projetos de Assentamento, áreas de garimpo, de agricultura familiar, de pecuária e de produção de grãos. Três percursos foram percorridos: de Itaituba a Uruará pela Transamazônica; de Itaituba a Novo Progresso pela BR-163 e Transgarimpeira; e a região de Santarém, Belterra e Mojuí dos Campos. A partir de entrevistas com informantes chaves e questionários semiestruturados 55 comunidades foram inventariadas. Foram abordadas questões relacionadas às características sociodemográficas, infraestrutura, saúde e educação, uso da terra e uso de recursos florestais. Foram realizados descrições e registros fotográficos sobre a infraestrutura das localidades. As comunidades e sedes dos municípios foram também mapeadas com dados de sensoriamento remoto e caracterizadas quanto aos seus limites e organização espacial interna. Para avaliar o refinamento do TerraClass 2010, foram avaliados pontos em campo referentes à classe urbana, observando-se confusões da ordem de 2% no mapeamento e imprecisão no limite dos polígonos. Os resultados indicam diferenças das comunidades visitadas de acordo com o contexto geográfico e com o histórico de formação. De modo geral, as comunidades distantes das estradas principais e das sedes dos municípios apresentam infraestrutura e serviços mais precários do que as que estão próximas às cidades e estradas, e assim estabelecem uma relação de dependência mais forte com outros núcleos populacionais e cidades. O aumento da escolaridade e a procura por emprego são fatores que influenciam a mobilidade da população, bem como atividades de melhoria de infraestrutura como a construção de hidrelétricas, pavimentação da BR-163 e atividades mineração. As mudanças no uso da terra, como o plantio mecanizado de grãos e o avanço da pecuária no sul do estado, produzem efeitos nos regimes de terras, na economia e na mobilidade. A análise específica dos diferentes aspectos levantados no campo será realizada em pesquisas posteriores. Os resultados desse trabalho serão comparados com os dados obtidos para as comunidades ribeirinhas, contribuindo para o melhor entendimento das relações de conectividade das localidades e estudos das redes urbanas do sudoeste paraense.