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Este estudo procura identificar o melhor modelo estatístico para modelar a intermitência dos ventos e avalia ocomportamento anual e sazonal do regime de ventos. Os dados anemométricos foram coletados na plataforma do Projeto SONDA em operação desde 2004 no Observatório Espacial do Sul em São Martinho da Serra, região central do Rio Grande do Sul. A série de dados compreende o período de 2005 a 2011. A partir do estudo foi possível traçar um perfil do potencial eólico para a região central do estado. Avaliação comparativa das distribuições estatísticas de Rayleigh, Weibull e Log Normal foi realizada. As distribuições de Weibull e Rayleigh apresentaram os melhores ajustes e menores desvios para o perfil eólico da região. Os valores de velocidade média, densidade de potência e fator de escala da distribuição de Weibull apresentaram pequena variação sazonal que pode favorecer a implantação de plantas eólicas na região. De modo geral, os ventos apresentam maiores frequências na direção sudeste ao longo do ano, porém, no Outono e Inverno, a direção noroeste também mostrou alta frequência. Concluiu-se, também, que as maiores densidades de potencia foram observadas na Primavera e no Inverno.

As pasture and cropland have replaced forest cover in the Brazilian Amazon, the creation of spatial explicit time series of land use is an important concern in modeling land change. Despite much progress in mapping deforestation using satellite remotely sensed data, little is known about the distribution of agricultural land uses that replace forest cover in the Brazilian Amazon.In this paper we present a methodology to integrate satellite remote sensing and census data over 1996/1997 and 2006/2007 periods. Our resulting land use maps show the distribution and proportion of pasture as well as, temporary and permanent agriculture across the region. More than show an overall expansion of the total agricultural area between 1997 and 2007, our mapped land use time series aim to describe the effects of land use changes across the region over one decade.

The purpose of this study was to assess the relative influence of remote wind stress on mean sea level (MSL) variations in the coastal region of Cananeia (Sao Paulo State, Southern Brazil) during the period from 1/1/1955 to 12/31/1993. An optimized low-pass Thompson filter for the study area, and spectral analysis (cross spectrum, coherence and phase lag) of the relationship between the MSL and both parallel (T//) and perpendicular (T|) wind stress components were applied. These were extracted from four grid points of the NCEP/NCAR global model. The predominance of annual oscillations as those of greatest coherence and energy, of periods of approximately 341 days (frequency of 0.00293 cpd) and 410 days (frequency of 0.00244 cpd), respectively, were observed. Offshore NCEP/NCAR grid points were those with the highest coherence and energy throughout the study in relation to the observed MSL. This may be linked to the restriction of the NCEP/NCAR model as regards the inland limit. It is also concluded that remote wind stress may play an important role in several MSL time scales, including the annual ones. Based on criteria such as coherence and energy peaks, the wind stress component of greatest effect on MSL was the parallel one.

In Brazil, plantations of exotic species such as Eucalyptus have expanded substantially in recent years, due in large part to the great demand for cellulose and wood. The combination of the steep slopes in some of these regions, such as the municipalities located close to the Serra do Mar and Serra da Mantiqueira, and the soil exposure that occurs in some stages in the Eucalyptus cultivation cycle, can cause landslides. The use of a geographic information system (GIS) assists with the identification of areas that are susceptible to landslides, and one of the GIS tools used is the spatial inference technique. In this work, the landslide susceptibility of areas occupied by Eucalyptus plantations in different stages of development in municipalities in the state of São Paulo was examined. Eight thematic maps were used, and, the fuzzy gamma technique was used for data integration and the generation of susceptibility maps, in which scenarios were created with different gamma values for the dry and rainy seasons. The results for areas planted with Eucalyptus were compared with those obtained for other land uses and covers. In the moderate and high susceptibility classes, the pasture is the land use type that presented the greatest susceptibility, followed by new Eucalyptus plantations and urban areas.

Tropical regions, especially the Amazon region, account for large emissions of methane (CH 4). Here, we present CH 4 observations from two airborne campaigns conducted within the BARCA (Balano Atmosférico Regional de Carbono na Amaznia) project in the Amazon basin in November 2008 (end of the dry season) and May 2009 (end of the wet season). We performed continuous measurements of CH 4 onboard an aircraft for the first time in the Amazon region, covering the whole Amazon basin with over 150 vertical profiles between altitudes of 500 m and 4000 m. The observations support the finding of previous ground-based, airborne, and satellite measurements that the Amazon basin is a large source of atmospheric CH 4. Isotope analysis verified that the majority of emissions can be attributed to CH 4 emissions from wetlands, while urban CH 4 emissions could be also traced back to biogenic origin. A comparison of five TM5 based global CH 4 inversions with the observations clearly indicates that the inversions using SCIAMACHY observations represent the BARCA observations best. The calculated CH 4 flux estimate obtained from the mismatch between observations and TM5-modeled CH 4 fields ranges from 36 to 43 mg m -2 d -1 for the Amazon lowland region.

This paper presents some parameters of negative cloud-to-ground lightning flashes in terms of frequency distribution. All data are based on so-called accurate-stroke-count studies from different climatological regions in the world and were already published in the literature with the exception of our measurements. We used GPS synchronized data from two digital high-speed cameras (at 18,000 frames/sec). The parameters considered in this study are: (1) continuing current duration, (2) time intervals between strokes, (3) number of strokes per flash and (4) total flash duration. The analysis includes Bergers data of Monte San Salvatore (Switzerland), which is the basis for lightning protection standards. The comparison suggests that despite of overall agreement of those parameters that some of them, currently used in protection standards, should be revised in order to be more realistic.

We present the results of airborne measurements of carbon monoxide (CO) and aerosol particle number concentration (CN) made during the Balan double dagger o Atmosf,rico Regional de Carbono na Amazonia (BARCA) program. The primary goal of BARCA is to address the question of basin-scale sources and sinks of CO2 and other atmospheric carbon species, a central issue of the Large-scale Biosphere-Atmosphere (LBA) program. The experiment consisted of two aircraft campaigns during November-December 2008 (BARCA-A) and May-June 2009 (BARCA-B), which covered the altitude range from the surface up to about 4500 m, and spanned most of the Amazon Basin. Based on meteorological analysis and measurements of the tracer, SF6, we found that airmasses over the Amazon Basin during the late dry season (BARCA-A, November 2008) originated predominantly from the Southern Hemisphere, while during the late wet season (BARCA-B, May 2009) low-level airmasses were dominated by northern-hemispheric inflow and mid-tropospheric airmasses were of mixed origin. In BARCA-A we found strong influence of biomass burning emissions on the composition of the atmosphere over much of the Amazon Basin, with CO enhancements up to 300 ppb and CN concentrations approaching 10 000 cm(-3); the highest values were in the southern part of the Basin at altitudes of 1-3 km. The Delta CN/Delta CO ratios were diagnostic for biomass burning emissions, and were lower in aged than in fresh smoke. Fresh emissions indicated CO/CO2 and CN/CO emission ratios in good agreement with previous work, but our results also highlight the need to consider the residual smoldering combustion that takes place after the active flaming phase of deforestation fires. During the late wet season, in contrast, there was little evidence for a significant presence of biomass smoke. Low CN concentrations (300-500 cm(-3)) prevailed basinwide, and CO mixing ratios were enhanced by only similar to 10 ppb above the mixing line between Northern and Southern Hemisphere air. There was no detectable trend in CO with distance from the coast, but there was a small enhancement of CO in the boundary layer suggesting diffuse biogenic sources from photochemical degradation of biogenic volatile organic compounds or direct biological emission. Simulations of CO distributions during BARCA-A using a range of models yielded general agreement in spatial distribution and confirm the important contribution from biomass burning emissions, but the models evidence some systematic quantitative differences compared to observed CO concentrations. These mismatches appear to be related to problems with the accuracy of the global background fields, the role of vertical transport and biomass smoke injection height, the choice of model resolution, and reliability and temporal resolution of the emissions data base.

In the Metropolitan Area of São Paulo (MASP), located in southeastern Brazil, surface ozone concentrations are often well above the national air quality standards. In this experimental study, we attempted to characterize the vertical profile of atmospheric ozone and transport of the ozone plume in the boundary layer, using data from the first ozone soundings ever taken in the MASP. In 2006, we launched fifteen ozonesondes: eight from 15 to 18 May (dry season); and seven from 30 October to 1 November (wet season). Vertical ozone mixing ratios in the troposphere were approximately 40 ppb, reaching maximum values of approximately 60 ppb during the dry-season campaign and approximately 100 ppb during the wet-season campaign. In the first and second campaigns, the mean tropospheric ozone column abundance was 28.2 and 41.3 DU, respectively, which can be attributed to the considerable variation in the annual temperature cycle over the region. To determine the effect that biomass burning has on ozone concentrations over the MASP, we analyzed wind trajectories and satellite-derived fire counts. We cannot state unequivocally that biomass burning contributed to higher ozone concentrations above the boundary layer during the experimental campaigns. In the boundary layer, ozone concentrations increase with altitude, peaking at the base of the inversion layer, suggesting that local emissions of volatile organic compounds and nitrogen oxides play a significant role in the lower troposphere over MASP, influencing ozone formation not only at the surface but also vertically in the atmosphere and in distant regions.

Cada vez mais são necessários programas de monitoramento da qualidade e quantidade da água como subsídios para avaliar as condições dos mananciais e, além disso, propiciar informações para a tomada de decisão com relação ao gerenciamento dos recursos hídricos. Este estudo analisou a qualidade e quantidade da água na microbacia do Ribeirão dos Macacos, afluente do rio Paraíba do Sul, Estado de São Paulo, por meio do monitoramento dos parâmetros: temperatura, pH, condutividade e oxigênio dissolvido, em cinco pontos da microbacia. As medições de vazão e altura da lâmina d água durante os períodos seco e úmido dos anos de 2010/2011, permitiram obter a curva chave em quatro pontos de monitoramento da qualidade da água e reconstruir as séries de vazões para estes períodos. Os resultados das análises mostraram que há um indicativo de mudanças nos parâmetros de qualidade da água devido às práticas conservacionistas adotadas. O parâmetro temperatura da água foi o mais influenciado pela sazonalidade da vazão. Diversos fatores físicos podem ter contribuído na correlação dos outros parâmetros com a vazão principalmente as diferentes ações de recuperação ambiental implantadas na área deste estudo e que visam uma maior sustentabilidade dos recursos hídricos.

We present a generic spatially explicit modeling framework to estimate carbon emissions from deforestation (INPE-EM). The framework incorporates the temporal dynamics related to the deforestation process and accounts for the biophysical and socioeconomic heterogeneity of the region under study. We build an emission model for the Brazilian Amazon combining annual maps of new clearings, four maps of biomass and a set of alternative parameters based on the recent literature. The most important results are: (a) Using different biomass maps leads to large differences in estimates of emission; for the entire region of the Brazilian Amazon in the last decade, emission estimates of primary forest deforestation range from 0.21 to 0.26 PgCyr−1. (b) Secondary vegetation growth presents a small impact on emission balance because of the short duration of secondary vegetation. In average, the balance is only 5% smaller than the primary forest deforestation emissions. (c) Deforestation rates decreased significantly in the Brazilian Amazon in recent years, from 27 Mkm2 in 2004 to 7 Mkm2 in 2010. INPE-EM process-based estimates reflect this decrease even though the agricultural frontier is moving to areas of higher biomass. The decrease is slower than a non-process instantaneous model would estimate as it considers residual emissions (slash, wood products and secondary vegetation). The average balance, considering all biomass, decreases from 0.28 in 2004 to 0.15 PgCyr−1 in 2009; the non-process model estimates a decrease from 0.33 to 0.10 PgCyr−1. We conclude that the INPE-EM is a powerful tool for representing deforestation-driven carbon emissions. Biomass estimates are still the largest source of uncertainty in the effective use of this type of model for informing mechanisms such as REDD+. The results also indicate that efforts to reduce emissions should focus not only on controlling primary forest deforestation but also on creating incentives for the restoration of secondary forests.