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As has been widely documented, lavishly funded media campaigns by political and financial elites and corporations with vested interests against climate policy are a central instigator of the climate backlash and a threat to democratic processes. However, it would behoove the environmental coalition, including sympathizing academics, to reflect on how they help create conditions that enable and magnify the impact of the backlash campaigns and incidents such as Climategate. This editorial argues that prevalent idealized understandings of science increase public vulnerability to backlash campaigns, and that academic analysts reinforce these understandings when they avoid to perform critical analyses of the science and scientists promoting concern about climate change.

Based on findings from ethnographic analysis of U.S. climate scientists, this article identifies largely unrecognized sociocultural dimensions underpinning differences in scientists’ perceptions of anthropogenic climate change. It argues that culturally laden tensions among scientists have influenced some to engage with the antienvironmental movement and, as such, influence U.S. climate science politics. The tensions are rooted in broad-based and ongoing changes within U.S. science and society since the 1960s and propelled by specific scientific subgroups’ negative experiences of the rise of environmentalism and of climate modeling, in particular. Attending to these and other experience-based cultural dynamics can help refine cultural theory and enhance understanding of the deeper battles of meaning that propel climate science politics.

An early assessment of national crop development conditions while the plants are still in the fields is highly needed to calculate correctly projections for decision-making and policies related to government planning andfood security. The aim of this study was to evaluate the suitability of NOAA /AVHRR 115296734 to detect changes in vegetation conditions, due to water stress during soybean crop, by means a combination of Land SurfaceTemperature (LST) and Normalized Difference Vegetation Index (NDVI). Both LST and NDVI data were combined and compared in a pixel basis over a soybeancrop area in Rio Grande do Sul State. The predicted theoretical inverse relationship for the combination of LST and NDVI was detected. An average increase of LST was observed in a normal crop cycle ( from 301.02 K to 308.36 K) compared to a crop cycle under water stress condition. An average reduction in NDVI was observed for normal crop cycle development (from 0.65 to 0.53) compared to a crop cycle under drought-induced effects. It was observed a higher correlation of municipality yield with LST (R2=0.78) than NDVI (R2=0.59). Results obtained indicate that the aggregation of AVHRR images, from Universidifferent institutions, provides the appropriate combination of spatial and temporal data LST and NDVI in order to detect the occurrence of drought stress, as well as its intensity, characterizing the conditions of the crop cycle development of soybean.

In this study, the concentration and morphological characteristics of inhalable particulate material (PM10) were evaluated and associated with climatic conditions. The mean annual concentration was 11.0 µg m−3, varying between 0,647 µg m−3 and 36.8 µg m−3. Wind speed has a higher influence on PM10 dispersion, but direction was associated with particle source. During the wet period, wind speed is the main dispersion factor, while speed and direction both are important during the dry period. Based on the morphological characteristics, it is concluded that biogenic particles prevail during the rainy season and terrigenous particles during the dry period, depending on the wind direction and intensity.

O pinhão manso (Jatropha curcas L.) tem encontrado obstáculos que dificultam seu sucesso como matéria-prima alternativa ao abastecimento da indústria do biodiesel. Estas barreiras puderam ser observadas por meio de um estudo de caso envolvendo o Brasil e a Índia, países com crescimento econômico destacado na última década, que possuem políticas para o biodiesel já estruturadas e pesquisas em andamento com a espécie. Há necessidade de estudos em toda cadeia produtiva, envolvendo aspectos agronômicos e tecnológicos. A possibilidade de incorporar áreas degradadas à agricultura para a produção de energia surge como grande atrativo e outras vantagens aparecem sob a ótica social, centrada na agricultura familiar. Concluiu-se que o êxito do pinhão manso nestes países está condicionado principalmente à caracterização das áreas de plantio e aos subsídios e incentivos destinados aos atores envolvidos no processo, especialmente, para que se evidenciem avanços na área de melhoramento genético, com a oferta de novos cultivares.

The biogeochemical dynamics of carbon in the ocean is a subject of fundamental interest to environmental studies. In this context, we have implemented a ten year run of the Brazilian Earth System Coupled Ocean-Atmosphere Model (BESM-OA2.3) integrated with TOPAZ biogeochemical model for the Atlantic basin. The modeled ΔpCO2 for the tropical Atlantic shows very clearly a high dominance of positive fluxes, that is, the CO2 fluxes are sea-to-air through- out the tropical region and for both winter and summer periods. In the mid-latitudes regions negatives fluxes (air-to-sea) were observed for both seasons. An exception to this pattern is an extensive negative tongue on the latitude 10°N. The occurrence of this negative ΔpCO2 tongue region in the Tropical Atlantic is highly correlated to negative Evapora- tion-Precipitation values during this season. In the northern hemisphere (NH) summer the negative values of ΔpCO2 in the tropical Atlantic region are concentrated in the adjacent zone of the Amazon river mouth due to the North Equatorial Counter Current intensification. This process favors the formation of a carbon sink in the adjacent region of the Amazon river mouth. Model results show lowest values of dissolved inorganic carbon (DIC) in a surface layer (100 – 150 m). Highest DIC values are observed in deeper layers and concentrated in an equatorial band. The chlorophyll bloom in equatorial zones was well represented by the model. These blooms are the result of equatorial upwelling that brings the high concentration tongues of DIC present in the equatorial band towards the euphotic zone. This is the first published paper about the BESM-OA2.3 integrated with TOPAZ. The presented results suggest that this modeling system is able to reproduce the main regional carbon dynamics features of the mid-latitude/tropical Atlantic.

In this study, we present the collation and analysis of the gridded land-based dataset of indices of temperature and precipitation extremes: HadEX2. Indices were calculated based on station data using a consistent approach recommended by the World Meteorological Organization (WMO) Expert Team on Climate Change Detection and Indices, resulting in the production of 17 temperature and 12 precipitation indices derived from daily maximum and minimum temperature and precipitation observations. High-quality in situ observations from over 7000 temperature and 11,000 precipitation meteorological stations across the globe were obtained to calculate the indices over the period of record available for each station. Monthly and annual indices were then interpolated onto a 3.75° × 2.5° longitude-latitude grid over the period 1901-2010. Linear trends in the gridded fields were computed and tested for statistical significance. Overall there was very good agreement with the previous HadEX dataset during the overlapping data period. Results showed widespread significant changes in temperature extremes consistent with warming, especially for those indices derived from daily minimum temperature over the whole 110 years of record but with stronger trends in more recent decades. Seasonal results showed significant warming in all seasons but more so in the colder months. Precipitation indices also showed widespread and significant trends, but the changes were much more spatially heterogeneous compared with temperature changes. However, results indicated more areas with significant increasing trends in extreme precipitation amounts, intensity, and frequency than areas with decreasing trends.

The reliability of predictions from climate and weather models is linked to an adequate representation of the land surface processes. To evaluate performance and to improve predictions, land surface models are calibrated against observed data. Despite an extensive literature describing methods of land surface model calibration, few studies have applied a calibration method for semiarid natural vegetation, especially for the semiarid northeast of Brazil, which presents caatinga as its natural vegetation. Caatinga is a highly dynamic ecosystem with the physics at the land surface-atmosphere interface still poorly understood. Therefore, in this study a multiobjective hierarchical method, which provides means to estimate optimal values of the model parameters through calibration, is evaluated. This method is applied to caatinga by using the Integrated Biosphere Simulator (IBIS). Results demonstrated that the calibrated set of vegetation parameters produced a considerably different energy balance from the default parameters. In general, the model was able to simulate the partition of the available energy into sensible and latent heat fluxes when the calibrated parameters were used. The IBIS model was not able to capture short-term, intense changes in latent heat flux from a dry condition to a wetter condition, however, even when the new set of calibrated parameters was used. Therefore, the parameter optimization may not be sufficient if processes are missing or misrepresented. This study is one of the first to understand the physics at the land surface-atmosphere interface in the caatinga ecosystem and to evaluate the ability of the IBIS model to represent the biophysical interactions in this important ecosystem.

A cobertura vegetal da superfície continental tem sido consideravelmente alterada pelas atividades humanas, principalmente através da conversão em grande escala da vegetação natural por áreas de cultivos e pastagens. Essas mudanças na cobertura da superfície podem alterar o clima regional e global por meio de processos biofísicos e biogeoquímicos. Assim, o presente trabalho avaliou como a substituição da vegetação natural da caatinga por agropecuária, bem como a degradação da caatinga, podem causar modificações nos processos de superfície na região semiárida do Nordeste do Brasil (NEB), a qual é uma das mais vulneráveis do Brasil, do ponto de vista social, à mudança de clima. Para isto, foram realizados experimentos numéricos de conversão da cobertura da superfície utilizando-se o modelo Integrated Biosphere Simulator IBIS. Por meio da conversão da cobertura vegetal, as características morfológicas e biofísicas da vegetação foram modificadas e por isso, causaram alterações nas componentes dos balanços de energia, de água e de carbono. O balanço de energia foi mais afetado pelo aumento do albedo decorrente da alteração da vegetação caatinga para agropecuária e para caatinga degradada. Além disso, as alterações do comprimento de rugosidade e das propriedades estomáticas da vegetação corroboraram para as alterações ocorridas nas trocas turbulentas entre a superfície e a atmosfera. Com relação às componentes do balanço de carbono, durante a estação chuvosa com a conversão da caatinga natural para agropecuária, houve um aumento da assimilação de CO2 (NEE) e com isso maior Produtividade Primária Líquida do ecossistema (NPP). O contrário ocorreu com a conversão para caatinga degradada, na qual a assimilação se manteve próxima de zero durante as horas do dia e NPP foi reduzida, o que pode ter ocorrido em função das alterações ocorridas no Índice de Área Foliar (IAF), tanto para a agropecuária, como para a caatinga degradada.

GPS time synchronized high-speed video records (at 4000 frames per second) and electric field waveforms are discussed for one stepped leader of a negative cloud-to-ground flash whose initial development becomes visible above cloud base. The leader emerges from the opaque region of the thundercloud around 4800 m above ground, propagating with speeds of the order of 106 m s -1. It is possible to see that this early, bright, and fast propagation period occurred simultaneously with the emission of initial breakdown bipolar pulse trains. The leader gradually reduces its speed and luminous intensity: When its tip is less than 3000 m above the ground, the propagation speeds oscillate between 2 and 4 × 105 m s -1 until it makes contact approximately 16 ms after it first became visible. With time, the initial breakdown waveform is gradually replaced by unipolar pulses and the leader propagation speed drops to the 105 m s-1 range. Key Points Fast visible leader development during the initial breakdown pulse activity Breakdown bipolar pulse trains become unipolar as the leader slows down.

Dados termopluviométricos são utilizados em diversos estudos. Contudo, a escassez de dados resultante da baixa densidade de estações meteorológicas é um problema frequentemente encontrado. Com isto, a utilização de dados estimados por satélites tem-se mostrado importante para regiões nas quais eles são escassos. Neste trabalho foram realizadas comparações entre dados mensais de precipitação pluvial estimados pelo satélite TRMM e de temperatura, estimados pelo satélite Aqua/MODIS aos dados observados por estações de superfície, para diferentes localidades do Estado de São Paulo, no período de 2003 a 2010. Os resultados demonstraram que para os dados de precipitação pluvial os menores erros foram observados nos meses de inverno e os maiores nos meses de verão. Em relação aos dados de temperatura observou-se que, com a inclusão de um fator de correção, os dados do satélite Aqua apresentaram boa exatidão em todos os meses. De maneira geral, os resultados obtidos indicam que os satélites TRMM e Aqua são alternativas eficientes na aquisição de informações em locais onde há falhas ou escassez dos mesmos podendo ser também utilizados na análise da consistência de dados coletados por meio de redes meteorológicas.