Extended time weather forecasts contributes to agricultural productivity estimates

Weather conditions in critical periods of the vegetative crop development influence crop productivity, thus being a basic parameter for crop forecast. Reliable extended period weather forecasts may contribute to improve the estimation of agricultural productivity. The production of soybean plays an important role in the Brazilian economy, because this country is ranked among the largest producers of soybeans in the world. This culture can be significantly affected by water conditions, depending on the intensity of water deficit. This work explores the role of extended period weather forecasts for estimating soybean productivity in the southern part of Brazil, Passo Fundo, and Londrina (State of Rio Grande do Sul and Paraná, respectively) in the 2005/2006 harvest. The goal was to investigate the possible contribution of precipitation forecasts as a substitute for the use of climatological data on crop forecasts. The results suggest that the use of meteorological forecasts generate more reliable productivity estimates during the growth period than those generated only through climatological information.     

Cloud condensation nuclei from biomass burning during the Amazonian dry-to-wet transition season

Aircraft measurements of cloud condensation nuclei (CCN) during the Large-Scale Biosphere–Atmosphere Experiment in Amazonia (LBA) were conducted over the Southwestern Amazon region in September–October 2002, to emphasize the dry-to-wet transition season. The CCN concentrations were measured for values within the range 0.1–1.0% of supersaturation. The CCN concentration inside the boundary layer revealed a general decreasing trend during the transition from the end of the dry season to the onset of the wet season. Clean and polluted areas showed large differences. The differences were not so strong at high levels in the troposphere and there was evidence supporting the semi-direct aerosol effect in suppressing convection through the evaporation of clouds by aerosol absorption. The measurements also showed a diurnal cycle following biomass burning activity. Although biomass burning was the most important source of CCN, it was seen as a source of relatively efficient CCN, since the increase was significant only at high supersaturations.     

Composition and sources of organic matter in atmospheric PM10 over a two year period in Beijing, China

The solvent-extractable organic compounds of atmospheric PM₁₀ samples, collected over two years beginning in 2003 at urban and suburban sites of Beijing, were characterized using gas chromatography–mass spectrometry (GC–MS). The elemental carbon (EC) contents were determined and ranged from 4.3 to 42 μg m^− 3. Organic compounds in total extracts were identified and included unresolved complex mixture (UCM) and series of n-alkanes, n-alkanols, n-alkanoic acids, polycyclic aromatic hydrocarbons (PAHs); saccharides, alkanedioic acids, steroids, and other biomarkers and source tracers. The seasonal variations of their relative abundances are discussed. The abundance order for the major molecular classes in the particulate organic matter (POM) was the following: UCM > saccharides > n-alkanoic acids >n-alkanes > n-alkanols > PAHs > hydroxy-PAHs > other biomarker tracers. Based on the genetic significance of the molecular tracers, the dominant sources of POM are proposed for the two sampling sites. The emissions from fossil fuel use (both coal and petroleum products), biomass combustion, other pyrolysis sources, higher plant wax, and secondary products contribute > 98.0% of the POM mass. The fossil fuel use (average = 65% of POM) is the largest contributor and derives mainly from vehicular traffic.     

Faint Lyman-break galaxies as a crucial test for galaxy formation models

It has recently been shown that galaxy formation models within the Λ cold dark matter cosmology predict that, compared to the observed population, small galaxies (with stellar masses  <10¹¹ M_⊙  ) form too early, are too passive since   z ∼ 3  and host too old stellar populations at   z = 0  . We then expect an overproduction of small galaxies at   z ≳ 4  that should be visible as an excess of faint Lyman-break galaxies. To check whether this excess is present, we use the morgana galaxy formation model and grasil spectrophotometric  +  radiative transfer code to generate mock catalogues of deep fields observed with Hubble Space Telescope Advanced Camera for Surveys. We add observational noise and the effect of Lyman α emission, and perform colour–colour selections to identify Lyman-break galaxies. The resulting mock candidates have plausible properties that closely resemble those of observed galaxies. We are able to reproduce the evolution of the bright tail of the luminosity function of Lyman-break galaxies (with a possible underestimate of the number of the brightest i -dropouts), but uncertainties and degeneracies in dust absorption parameters do not allow to give strong constraints to the model. Besides, our model shows a clear excess with respect to observations of faint Lyman-break galaxies, especially of   z ₈₅₀∼ 27 V   -dropouts at   z ∼ 5  . We quantify the properties of these 'excess' galaxies and discuss the implications: these galaxies are hosted in dark matter haloes with circular velocities in excess of 100 km s⁻¹, and their suppression may require a deep rethinking of stellar feedback processes taking place in galaxy formation.     

Earth-Based Support for the Titan Saturn System Mission

The Titan Saturn System Mission (TSSM) concept is composed of a TSSM orbiter provided by NASA that would carry two Titan in situ elements provided by ESA: the montgolfière and the probe/lake lander. One overarching goal of TSSM is to explore in situ the atmosphere and surface of Titan. The mission has been prioritized as the second Outer Planets Flagship Mission, the first one being the Europa Jupiter System Mission (EJSM). TSSM would launch around 2023–2025 arriving at Saturn 9 years later followed by a 4-year science mission in the Saturn system. Following delivery of the in situ elements to Titan, the TSSM orbiter would explore the Saturn system via a 2-year tour that includes Enceladus and Titan flybys before entering into a dedicated orbit around Titan. The Titan montgolfière aerial vehicle under consideration will circumnavigate Titan at a latitude of ~20° and at altitudes of ~10 km for a minimum of 6 months. The probe/lake lander will descend through Titan’s atmosphere and land on the liquid surface of Kraken Mare (~75° north latitude). As for any planetary space science mission, and based on the Cassini–Huygens experience, Earth-based observations will be synergistic and enable scientific optimization of the return of such a mission. Some specific examples of how this can be achieved (through VLBI and Doppler tracking, continuous monitoring of atmospheric and surface features, and Direct-to-Earth transmission) are described in this paper.     

Modelling the effects of dust evolution on the SEDs of galaxies of different morphological type

We present photometric evolution models of galaxies, in which, in addition to the stellar component, the effects of an evolving dusty interstellar medium have been included with particular care. Starting from the work of Calura et al., in which chemical evolution models have been used to study the evolution of both the gas and dust components of the interstellar medium in the solar neighbourhood, elliptical and irregular galaxies, it has been possible to combine these models with a spectrophotometric stellar code that includes dust reprocessing ( grasil ) to analyse the evolution of the spectral energy distributions (SEDs) of these galaxies. We test our models against observed SEDs both in the local universe and at high redshift, and use them to predict how the percentage of reprocessed starlight evolves for each type of galaxy. The importance of following the dust evolution is investigated by comparing our results with those obtained by adopting simple assumptions to treat this component.     

Application of the K?ppen classification for climatic zoning in the state of Minas Gerais, Brazil

The knowledge of the climatic conditions of a region is crucial for its agricultural development. It is also extremely important for understanding the fact that certain cultures have to develop under prevailing temperature and humidity conditions and assist in the adoption of a suitable irrigation technique, as well as its management and operationalization. The K?ppen system of climate classification is widely used for the identification of homogeneous climate zones as it considers only rainfall and temperature as the meteorological elements for classification. For this study, we used climatic databases of rainfall and temperature in a raster format, with a spatial resolution of 30″ of arc (an approximate area of 0.86?km²?pixel^?1), from 1961 to 1990. Through geoprocessing techniques, we obtained a map of climatic classification for the state of Minas Gerais. We found that the state has the following three major climatic groups: A, B and C, which correspond to tropical rainy, dry and warm temperate climates, respectively. The climate classes obtained were Aw, Am, BSh, Cwa and Cwb, with Aw, Cwa and Cwb classes occupying 99.89% of the territorial area of the state. The validation of the results showed a satisfactory agreement, with 93.75% reliability.     

The use of geoprocessing to assess vulnerability on the east coast aquifers of Rio de Janeiro State,Brazil

The east coast of Rio de Janeiro State, Brazil, shows a worrying overlap between areas with intrinsic groundwater vulnerability and the most significant urban expansion zones. It experienced a rapid population growth in recent years, mainly due to the tourism industry, resulting in a significant pressure on drinking groundwater resources. In this regard, development and use of techniques to control and protect areas susceptible to contamination is crucial. The elaboration of aquifer vulnerability maps is thus extremely helpful to support water resources management. The aim of the work is to present the methodological approach in the use of Geoprocessing techniques to obtain a suitable groundwater vulnerability model in Rio de Janeiro east coast. Considering the existing problems and the current land use and characteristics of the study region, it is clear that the most vulnerable areas (that is, “extreme” and “very high” vulnerability areas), coincide with the most significant zones of urban occupation, corresponding to 11% of the total study area, demanding adoption of urgent measures in the near future. Geoprocessing tools and remote sensing for characterization of Rio de Janeiro’s east coast aquifer vulnerability gave good results, representing a satisfactory method for management actions at low cost.     

“My Paper, My Paper”: Reflections on the embodied production of postcolonial geographical responsibility in academic writing

This article asks the question: what are my responsibilities as a postcolonial geographical writer? It takes as its starting point three extracts from texts written by the writer on their journey towards becoming an academic: a catalyst moment, a moment of self-production as an academic, and a moment of (failed) academic production. This journey raises a problematic around the ways in which the body speaks in academic writing, and the remainder of the piece reviews the geographical literature on materiality in relation to the body, arguing that Deleuzian views of matter as agentic and creative are particularly helpful in comprehending and engaging responsibly with the indeterminate but insistent ways in which the body speaks in postcolonial academic writing.     

Social segregation and academic achievement in state-run elementary schools in the municipality of Campinas, Brazil

Space not only reflects social inequality, it also reinforces the advantages or disadvantages associated with social class. However, the study of how neighbourhoods affect their residents has only recently entered the debate on urban poverty in Latin America. We use 2000 data from the Brazilian population census, school census, and the state of São Paulo’s educational evaluation system to analyze the relationship between school infrastructure, school academic achievement, and the neighbourhoods in which these schools are located. Our analyses indicate that state-run elementary schools located in areas of concentrated poverty have lower academic achievement in mathematics tests and Portuguese than mixed and affluent areas of the city, even though these schools are all administered by the same government body. We end with a discussion of the relationship between Brazilian education policy and its influence on spatial differences in São Paulo State.