Publicações

A ligação entre mudança climática e desenvolvimento sustentável foi dada pela aplicação do Mecanismo do Desenvolvimento Limpo (MDL) do Protocolo de Kyoto, uma ferramenta baseado no mercado que incentiva a redução das emissões de gases de efeito estufa e promove o desenvolvimento sustentável por meio de projetos implementados nos países em desenvolvimento. Assim um dos incentivos desses países para participar no MDL estaria de atrair fontes de investimentos, por exemplo, para o fortalecimento da sua economia, para a geração de renda nas comunidades locais, para a criação de oportunidades de emprego. Neste sentido, o objetivo do trabalho é descrever a participação da América Latina no MDL, no período de 2005-2012, com foco em três países, Brasil, México e Peru, explicitando suas características, os setores que foram mais atraentes para atividades de MDL, a evolução de projetos registrados desde que o Protocolo de Kyoto entrou em vigor até o final do seu primeiro período de compromisso, os investimentos que foram recebidos via MDL e as políticas nacionais voltadas para o desenvolvimento de baixo carbono.

Esta pesquisa apresenta um panorama da sustentabilidade em sete municípios paraenses, que fazem parte do polo de produção do dendê (Elaeis guineensis Jacq.) na Amazônia oriental. Trata-se de uma área com aproximadamente 46.000 km² que apresenta diferentes padrões de usos da terra, considerada prioritária para a implementação da política nacional dos biocombustíveis por apresentar grandes extensões de terras em condições edafoclimáticas favoráveis. A pesquisa, utilizando o Barômetro da Sustentabilidade BS, faz uma avaliação ex ante do nível de desenvolvimento dos municípios, analisando dados quantitativos e qualitativos de diferentes fontes a partir de 2010. Foram empregados dezesseis indicadores para o bem-estar humano (social) e nove para o bem-estar ecológico (ambiental), ajustados à escala do Barômetro. Os resultados do BS mostraram que os municípios ocupam posições intermediárias e potencialmente insustentáveis, o que reflete a fragilidade socioeconômica e ambiental da região estudada.

Image segmentation is a fundamental step in several image processing tasks. It is a process where an image is divided into its constituent regions guided by a similarity criterion. One very interesting image segmentation method is the color structure code (CSC), which combines simultaneously split-and-merge and region-growing techniques. In this paper, a segmentation approach based on the CSC method, weighted color structure code (WCSC), is proposed. This method is guided by a nonlinear discrimination function, where the user-inference is captured by the Polynomial Mahalanobis distance, prioritizing, during the merging process, the regions with higher similarity to the user selected pattern. TheWCSC has color distribution pattern-oriented characteristic, showing better coherence among the segments with higher similarity to the selected pattern. A qualitative evaluation and parametric paired analysis were performed to compare CSC, WCSC and other segmentation methods results, using images from Berkeley benchmark. The results from these comparison indicate an improvement on the segmentation result obtained by the WCSC.

The aim of this paper is to explore possible links between forest cover change and characteristics of social-ecological systems at sub-national scale based mainly on census data. We assessed relationships between population density, poverty, ethnicity, accessibility and forest cover change during the last decade for four regions of Bolivia and the Lao PDR, combining a parcel-based with a cell-based approach. We found that accessibility is a key driver of forest cover change, yet it has the effect of intensifying other economic and policy-related underlying drivers, like colonization policies, cash crop demand, but also policies that lead to forest gain in one case. Poverty does not appear as a driver of deforestation, but the co-occurrence of poverty and forest loss driven by external investments appears critical in terms of social-ecological development. Ethnicity was found to be a moderate explanatory of forest cover change, but appears as a cluster of converging socio-economic characteristics related with settlement history and land resource access. The identification of such clusters can help ordering communities into a typology of social-ecological systems, and discussing their possible outcomes in light of a critical view on forest transition theory, as well as the relevance and predictive power of the variables assessed.

The South American Biomass Burning Analysis (SAMBBA) field campaign took detailed in situ flight measurements of aerosol during the 2012 dry season to characterise biomass burning aerosol and improve understanding of its impacts on weather and climate. Developments have been made to the Weather Research and Forecast model with chemistry (WRF-Chem) model to improve the representation of biomass burning aerosol in the region, by coupling a sectional aerosol scheme to the plume-rise parameterisation. Brazilian Biomass Burning Emissions Model (3BEM) fire emissions are used, prepared using PREP-CHEM-SRC, and mapped to CBM-Z and MOSAIC species. Model results have been evaluated against remote sensing products, AERONET sites, and four case studies of flight measurements from the SAMBBA campaign. WRF-Chem predicted layers of elevated aerosol loadings (520 µg sm−3 ) of particulate organic matter at high altitude (68 km) over tropical forest regions, while flight measurements showed a sharp decrease above 24 km altitude. This difference was attributed to the plume-rise parameterisation overestimating injection height. The 3BEM emissions product was modified using estimates of active fire size and burned area for the 2012 fire season, which reduced the fire size. The enhancement factor for fire emissions was increased from 1.3 to 5 to retain reasonable aerosol optical depths (AODs). The smaller fire size lowered the injection height of the emissions, but WRF-Chem still showed elevated aerosol loadings between 45 km altitude. Over eastern cerrado (savannah-like) regions, both modelled and measured aerosol loadings decreased above approximately 4 km altitude. Compared with MODIS satellite data and AERONET sites, WRF-Chem represented AOD magnitude well (between 0.31.5) over western tropical forest fire regions in the first half of the campaign, but tended to over-predict them in the second half, when precipitation was more significant. Over eastern cerrado regions, WRF-Chem tended to underpredict AODs. Modelled aerosol loadings in the east were higher in the modified emission scenario. The primary organic matter to black carbon ratio was typically between 810 in WRF-Chem. This was lower than the western flight measurements (interquartile range of 11.615.7 in B734, 14.724.0 in B739), but similar to the eastern flight B742 (8.110.4). However, single scattering albedo was close to measured over the western flights (0.870.89 in model; 0.860.91 in flight B734, and 0.810.95 in flight B739 measurements) but too high over the eastern flight B742 (0.860.87 in model, 0.790.82 in measurements). This suggests that improvements are needed to both modelled aerosol composition and optical properties calculations in WRF-Chem.

This study aims to analyze how the visible parameters of cloud-to-ground discharges such as the flash multiplicity and duration, the interstroke interval, the continuing current duration and the number of ground contacts per flash vary between observations conducted on different days. Several authors have already analyzed these parameters for groups of thunderstorms in some regions. Although some authors did not find differences on those characteristics for different regions, there has not been a comprehensive amount of lightning recordings from the same thunderstorm in order to evaluate such parameters in a storm-to-storm basis. The lightning data for this work was obtained by four high-speed cameras set to operate at 2500 framesper second. They were locatedinSão JosédosCampos,Brazil, andinitsneighboring region as part of the RAMMER project (Portuguese acronym for Automated Multi-Camera Network for Monitoring and Study of Lightning Flashes). Five thunderstorm days were selected for this study, during which a total of 361 flashes were recorded. This is the first study in which four high-speed cameras observed the same thunderstorm from different locations. Because of the number of cameras and their positions, the coverage area is larger than usual single-camera studies, thereby increasing the number of flashes recorded from the same thunderstorm. These larger samples allow a more representative analysis of the lightning parameters mentioned above.

In a social-environmental modeling course, students need to learn complementary skills that include the conceptualisation of a model, different modeling paradigms, computer programming, and the process of rigorously converting ideas and data into a computational program using a given toolkit. Such topics need to be taught in parallel in order to keep a heterogeneous audience motivated. Based on the experience with multidisciplinary audiences, this paper describes a socio-environmental modeling course that explores three modeling paradigms: System dynamics, Cellular automata, and Agent-based modeling. We also present a small tutorial with some examples developed for the course.

Sugarcane is a typical culture of hot and humid climate and therefore is well adapted to the climate in many regions of Brazil. However, there may be yield reductions in the Northeastern region of Brazil due to possible future reductions in rainfall levels. The aim of this study was to simulate, using the Century 4.5 model, the impact of climate changes on potential sugarcane yield in Goiana and Itambé, Zona da Mata of Pernambuco. The Century 4.5 model was booted with soil and climate data from 1950 to 2012. Data on total soil carbon, soil texture (sand, silt and clay contents), pH, soil density and soc stocks were obtained from previous studies. The climate scenario used was the average emissions SRES A1B, designed by Eta/CPTEC model for periods 20142040, 20412070 and 20712100, which is composed of LOW member (low emissions) and HIGH member (high emissions). According to the results obtained by A1B scenario, the potential yield can be reduced in the near future (20142040). The high temperatures in northeastern Brazil will increase the evapotranspiration rates, reducing the amount of water available in the soil, making the planting of sugarcane increasingly difficult, which tend to be strongly reduced in drier areas, such as cities located in the western portion of the Zona da Mata region, northern state of Pernambuco, Brazil.

We present a new segmentation method called Weighted Felzenszwalb and Hutten-locher method (WFH), an improved version of the well-known graph-based segmentation method, Felzenszwalb and Huttenlocher method (FH). Our method uses a non-linear discrimination function based on Polynomial Mahalanobis Distance (PMD) as the color similarity metric. Two empirical validation experiments were performed using as a golden standard ground truths from a publicly available source, the Berkeley dataset, and an objective segmentation quality measure, the Rand dissimilarity index. In the first experiment the results were compared against the original FH method. In the second, WFH was compared against several well-known segmentation methods. In both cases WFH presented significant better similarity results when compared with the golden standard and segmentation results presented a reduction of over-segmented regions.

Urbanization and land use changes alter the nitrogen (N) cycle, with critical consequences for continental freshwater resources, coastal zones, and human health. Sewage and poor watershed management lead to impoverishment of inland water resources and degradation of coastal zones. Here we review the N contents of rivers of the three most important watersheds in South America: the Amazon, La Plata, and Orinoco basins. To evaluate potential impacts on coastal zones, we also present data on small- and medium-sized Venezuelan watersheds that drain into the Caribbean Sea and are impacted by anthropogenic activities. Median concentrations of total dissolved nitrogen (TDN) were 325 μg L-1 and 275 μg L-1 in the Amazon and Orinoco basins, respectively, increasing to nearly 850 μg L-1 in La Plata Basin rivers and 2000 μg L-1 in small northern Venezuelan watersheds. The median TDN yield of Amazon Basin rivers (approximately 4 kg ha-1 yr-1) was larger than TDN yields of undisturbed rivers of the La Plata and Orinoco basins; however, TDN yields of polluted rivers were much higher than those of the Amazon and Orinoco rivers. Organic matter loads from natural and anthropogenic sources in rivers of South America strongly influence the N dynamics of this region.

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.