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We review the carbon balance and trends over the last decades, as well as their determinants, for South America as part of a catalogue of similar regional syntheses covering the globe for the RECCAP (REgional Carbon Cycle Assessment and Pro- 5 cesses) effort. South America as a region has attracted the attention of global carbon cycle and climate researchers mainly because of the very large amount of organic carbon stored in its rainforests. Amazonia contains on the order of 95120 PgC in living biomass and additional 160 PgC in soils (Gibbs et al., 2007; Malhi et al., 2006; Saatchi et al., 2011; Jobaggy and Jackson 2000; Appendix 2). To place this in perspective in 10 total this is approximately half of the amount of carbon contained in the atmosphere before the beginning of the industrialization in the 18th century. A substantial fraction of these carbon pools is thus amenable to release to the atmosphere on short timescales (decades) by deforestation. On the other hand, because of their vast size the forests also have the potential to slightly moderate the global carbon problem by taking 15 up carbon and thereby mitigating some emissions due to the burning of fossil fuels. However, this effect will eventually saturate. Hence two main factors will likely dictate future changes in forest biomass. Firstly, the current fast demographic and economic development (e.g., Soares-Filho et al., 2006), and secondly changes in forest biomass and biome boundaries caused by changes in atmospheric gas composition and any 20 associated climate change (e.g., Phillips et al., 2009; Marimon et al., 2006). The development of the region is associated directly with forest destruction mainly for agricultural use (e.g., DeFries et al., 2010), while changes brought about by altered climate and atmospheric composition on forests are subtler. Specifically, increases in carbon dioxide concentration and/or changes in direct light may stimulate tree growth 25 and in turn rainforest biomass gains (Lloyd and Farquhar, 1996; Mercado et al., 2009). There is strong evidence for such a process having occurred over the last decades and is still ongoing (Phillips et al., 1998, 2009; Lewis et al., 2009). In contrast the changing climate has also been hypothesized to have adverse effects on tropical rainforests. As for other parts of the globe, warming of the Earths surface is predicted to result in an increase in climate variation in South America (Held and Soden, 2006) including likely increased frequency and intensity of dry periods. Such increased variation, together with a general global warming, may possibly lead to forest decline through enhanced 5 water stress, and drought induced forest loss may be further amplified by fire (White et al., 1999; Cox et al., 2000; Poulter et al., 2010; Nepstad et al., 1999; Aragao and Shimabukuro, 2010). Altogether it is the interplay between the very large area covered by high carbon density intact forests, and the very fast economical and demographic development and a changing climate, which make South America of particular interest 10 for its role in the contemporary carbon cycle and, in turn, to climate over the decades to come. The purpose of this study is to give a state of the art assessment of South American carbon stocks, fluxes and time trends, and their dominant controls. Further, we will assess the role of South America in the carbon cycle over the last decades in or15 der to provide an indication for what to expect in the decades to come. The paper is structured as follows. We start with a characterization of main biomes, stocks, mean climate, climate trends, demography and economic development. We then present and discuss stocks and carbon fluxes associated with different processes and estimated using complementary methods. Dominant processes, in a loose sense, fall into 20 the categories of fossil fuel emissions, deforestation, agriculture and trade, and rainforest tree growth trends. We then also discuss inferences from atmospheric greenhouse gas concentration patterns on carbon sources and sinks using atmospheric transport inverse modelling and vegetation model estimates, whilst recognising these two methods are still in stages of development.

O trabalho avalia a evolução espacial e temporal de informações socioespaciais para os nove municípios da Região Metropolitana da Baixada Santista (RMBS), São Paulo, sob a ótica da política. Se o mote da criação dessa região metropolitana foi o intenso e rápido processo de metropolização, com consequências variadas para a população e ambiente englobando desde o crescimento da renda e do emprego até processos de segregação socioespacial hoje, enquanto Região Metropolitana legalmente instituída, a Baixada Santista enfrenta dilemas que devem ser discutidos no seu conjunto. No mesmo horizonte de expansão dos serviços e investimentos convivem disputas de diversos atores, pelo uso do territorio, em um contexto de metropolização parcialmente consolidado. O período analisado (última década) revela que as diferenças entre municípios têm se ampliado, fato que atesta que os princípios de solidariedade e coesão que deveriam nortear a RMBS não estão sendo cumpridos. Este trabalho integra o projeto temático FAPESP 2008/58161-1, que visa avaliar impactos e vulnerabilidade de setores brasileiros às mudanças climáticas globais.

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.