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Nowadays, agricultural commodity market requires more efficient and better control of information on crop production. Due to characteristics of Brazil, in this market, the attainment of reliable and timely agricultural estimates is very important. The objective of this study was to evaluate the coupled models performance of crop area and crop productivity estimates, for an adequate temporal and spatial resolution. The productivity model proposed is complementarily added to the previously developed model of crop area estimate. The coupled model results were compared to Brazilian Institute of Geography and Statistics (IBGE) data, in a State and municipality level. Both, MODIS Crop Detection Model (MCDM) and MODIS Productivity Detection Model (MPDM) were developed at the National Institute for Space Research (INPE) and use analysis of the temporal-spectral profile of agricultural crop development, achieved with EVI/MODIS images. Results indicate that application of the coupled model is able to generate timely crop area and productivity estimates for soybean in the Rio Grande do Sul in a municipality level. In a State level, estimates of MPDM from 2001 to 2008, obtained R 2 =0.89, with a higher deviation for 2002. R 2 =0.96 were obtained by subtracting harvest of 2002 from the analysis. Kriging productivity maps, of MPDM and IBGE, were compared and shown a visual similarity in their spatial distribution and development trend.

Cada vez mais, as pesquisas realizadas na Amazônia têm demonstrado a importância dessa região para o equilíbrio do meio ambiente na América do Sul. Nessa linha, este trabalho tem por objetivo o estudo dos efeitos das mudanças globais na bacia do Rio Madeira. Para isso, foi utilizado o downscaling dinâmico de cenários de mudanças climáticas desenvolvidos no CPTEC-INPE, juntamente com cenários futuros de uso do solo, para obter cenários hidrológicos na bacia com o uso do Modelo Hidrológico de Grandes Bacias do INPE. Realizou-se a correção do bias nos campos de precipitação simulados, utilizando informações pluviométricas existentes no CPTEC-INPE, previamente consistidas. Efetuaram-se simulações do tempo presente e projeções do futuro, com cada um dos 4 cenários regionais do CPTEC-INPE. Com a utilização do Modelo Hidrológico de Grandes Bacias do Instituto Nacional de Pesquisas Espaciais (MGB-INPE), foram realizadas as projeções hidrológicas nos períodos de 1961 a 1990 e 2011 a 2099, comparando-as a partir de seus valores de Precipitação, Evapotranspiração e Vazão. Assim, pode-se identificar as alterações nas sazonalidades e ocorrências de valores extremos. Fez-se uso das curvas de permanência, para relacionar a Precipitação e Vazão com a probabilidade de ocorrerem ao longo do tempo. Ainda com esses dados, trabalhou-se com a climatologia de cada sub-bacia (11 no total) do Rio Madeira. Nas análises elaboradas, pode-se perceber o aumento dos valores de Evapotranspiração e, em geral, a diminuição da Precipitação, enquanto a Vazão decresce nos cenários futuros.

Meteorological and environmental aspects are the number one cause of electric utility power distribution interruptions all over the planet. In Brazil, about 40-50% of the interruptions in the distribution systems are caused only by lightning. In this work is described a new computational system called CLIMA 1.0 that integrates meteorological and environmental parameters, including surface temperature, humidity, wind intensity and direction, and precipitation, all provided by a mesoscale WRF model, vegetation information, provided by satellite high resolution images, and total lightning information, provided by the Brazilian lightning detection network (BrasilDat), into a geographical information system (GIS) platform, which contains the information about the EDP distribution system located in the southeastern region of Brazil. The system should contribute to the EDP effort to implement smart grids.

O conhecimento do comportamento das geadas no RS é bem relevante, considerando seu impacto na agricultura. Sabe-se que sua ocorrência está vinculada a mudanças na circulação atmosférica, que podem ser afetadas pelo ENOS. Mas o ENOS interage com outros padrões, especialmente a ODP. Neste trabalho foram investigadas as relações, simultâneas e defasadas, entre os eventos de geada no RS, ocorridos no mês de junho e eventos ENOS, observando se estas têm significância estatística diferente de acordo com as diferentes fases da ODP. Para isso, foram utilizadas tabelas de contingência 3×3, avaliadas por um teste baseado numa distribuição hipergeométrica (Teste de Fisher). Observou-se que quando há La Niña, ocorrem mais geadas, na maioria das estações estudadas, e quando há El Niño, menos geadas. Os resultados também apontam que estas relações existem mais significativamente na fase negativa da ODP e são mais intensas para defasagem de 1 mês.

Several works deal with lightning warning methods developed from CG lightning locations systems (LLS) [Murphy and Cummins, 2000; Murphy, Demetriades and Cummins, 2002; Holle, Murphy and Lopez, 2003]. Additionally, other particular works combine total lightning with weather radar information in an effort to improve the accuracy of lightning threat alarms [Murphy and Holle, 2005; 2006]. Finally, some recent studies presented automated lightning warning systems as a combination of lightning detection information and data from one or more electric field mills (EFMs) [Murphy, Holle and Demetriades, 2008; Murphy and Cummins, 2000; Montanya et al., 2008; Beasley, Williams and Hyland, 2008]. These studies had shown that the EFM measurements are strongly affected by the local characteristics where it was installed (for example the cloud charge center height in that region, the topography, etc.). Thus, the effectiveness of lightning warning methods using electric field data changes from one region to another. It is important to note that all these past studies took place in the Northern hemisphere. This paper presents the characteristics of an EFM network that is being installed in the South hemisphere, particularly in Southeastern Brazil (Figure 1). It is also presented the proposed methodology to generate lightning risk warning in order to evaluate how the atmospheric electric field data can be used to support the decision-making process for issuing a lightning risk warning.

The study was conducted in the Araripe plasterer pole located at Piaui, Pernambuco and Ceara border, Brazil, with an area of approximately 10,000 km2. The region is experiencing an accelerated degradation process due to improper management of natural resources. Extensive areas of native forests are being cleared and used for energy production for the gypsum industry. In 1997, it was created the Araripe Environmental Protection Area (APA), in order to reduce and mitigate environmental degradation processes. The purpose of this APA was not to stop the activity in that region, but to adapt it in a sustainable manner, since the plaster pole is over an area of high vulnerability to desertification processes. The inappropriate use of natural resources in this region may intensify the environmental problems and accelerate the desertification process. Thus, the aim of this paper is to monitor the environmental degradation in the APA region during a period of 16 years, and evaluate if this region is been preserved since APA creation. To achieve the proposed aim we mapped deforestation and natural forest from 1990 to 2006 (one image every four years) using Landsat TM 5. We applied the Linear Spectral Mixing Model and we did a band ration between the resulting vegetation and soil bands which allowed a better identification of deforested areas. The results show that the deforestation had decreased since the APA creation and thus had a positive effect on the preservation of this vulnerable area.

A Caatinga brasileira possui atualmente metade de sua cobertura vegetal original. De acordo com os dados do monitoramento do MMA, a principal causa da degradação da Caatinga deve-se à extração da mata nativa, que é convertida em lenha e carvão vegetal, sendo a porção pernambucana da Chapada do Araripe uma das áreas mais degradadas. A área de proteção ambiental da Chapada do Araripe, com aproximadamente 10.000 km², passa por um processo de degradação acentuada. Além do desmatamento da vegetação natural para a produção de lenha, a região também sofre com as constantes queimadas, que podem ser de origem antrópica ou natural. Neste contexto, o presente estudo quantificou os focos de calor nos anos de 1998, 2003 e 2006 associando ao desmatamento e com dados de precipitação.

The industrial and social development of a country requires large amounts of energy, particularly electricity. To follow the development with an efficient power grid, the human society has sought alternative energy sources that are economically and ecologically viable. The wind energy is one of such alternatives. However, the deployment of wind farms requires a previous study of the winds statistical profile in the region of interest. With this in mind, this work performs an analysis of three different statistical distributions to see which best fits the wind profile in the Central Region of the South of Brazil. The Weibull, Log Normal and Rayleigh statistical distribution were studied and compared with the values of wind speed collected at 50 meters from the SONDA site operating in São Martinho da Serra, RS in the Southern Space Observatory – OES/CRS/CCR/INPEMCT. The analysis was performed