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Sala S.,European Commission - Joint Research Center Ispra
Integrated environmental assessment and management | Year: 2013

The development and use of footprint methodologies for environmental assessment are increasingly important for both the scientific and political communities. Starting from the ecological footprint, developed at the beginning of the 1990s, several other footprints were defined, e.g., carbon and water footprint. These footprints-even though based on a different meaning of "footprint"-integrate life cycle thinking, and focus on some challenging environmental impacts including resource consumption, CO2 emission leading to climate change, and water consumption. However, they usually neglect relevant sources of impacts, as those related to the production and use of chemicals. This article presents and discusses the need and relevance of developing a methodology for assessing the chemical footprint, coupling a life cycle-based approach with methodologies developed in other contexts, such as ERA and sustainability science. Furthermore, different concepts underpin existing footprint and this could be the case also of chemical footprint. At least 2 different approaches and steps to chemical footprint could be envisaged, applicable at the micro- as well as at the meso- and macroscale. The first step (step 1) is related to the account of chemicals use and emissions along the life cycle of a product, sector, or entire economy, to assess potential impacts on ecosystems and human health. The second step (step 2) aims at assessing to which extent actual emission of chemicals harm the ecosystems above their capability to recover (carrying capacity of the system). The latter step might contribute to the wide discussion on planetary boundaries for chemical pollution: the thresholds that should not be surpassed to guarantee a sustainable use of chemicals from an environmental safety perspective. The definition of what the planetary boundaries for chemical pollution are and how the boundaries should be identified is an on-going scientific challenge for ecotoxicology and ecology. In this article, we present a case study at the macroscale for the European Union, in which the chemical footprint according to step 1 is calculated for the year 2005. A proposal for extending this approach toward step 2 is presented and discussed, complemented by a discussion on the challenges and the use of appropriate methodologies for assessing chemical footprints to stimulate further research and discussion on the topic. © 2013 SETAC. Source

De Longueville Bertrand B.,European Commission - Joint Research Center Ispra
Computers, Environment and Urban Systems | Year: 2010

User-generated content, interoperability and the social dimension are the cornerstones of an emerging paradigm for the creation and sharing of information: Web 2.0. This article studies how geoportals can benefit from the Web 2.0 features. Geoportals are World Wide Web gateways that organize content and services related to geographic information. They are the most visible part of Spatial Data Infrastructures (i.e. distributed systems that aid acquisition, processing, distribution, use, maintenance, and preservation of spatial data). Today's geoportals are focusing on interoperability through the implementation of standards for discovery and use of geographic data and services. Will tomorrow's Geoportals focus more on organising communities of users sharing common interests? Recent papers are arguing for deeper integration of the Web 2.0 paradigm within the geospatial web. This article aims to provide an overview supporting the next generation geoportal development by defining related concepts, by emphasising advantages and caveats of such an approach, and proposing appropriate implementation strategies. © 2010 Elsevier Ltd. Source

Mayaux P.,European Commission - Joint Research Center Ispra
Philosophical transactions of the Royal Society of London. Series B, Biological sciences | Year: 2013

This paper presents a map of Africa's rainforests for 2005. Derived from moderate resolution imaging spectroradiometer data at a spatial resolution of 250 m and with an overall accuracy of 84%, this map provides new levels of spatial and thematic detail. The map is accompanied by measurements of deforestation between 1990, 2000 and 2010 for West Africa, Central Africa and Madagascar derived from a systematic sample of Landsat images-imagery from equivalent platforms is used to fill gaps in the Landsat record. Net deforestation is estimated at 0.28% yr(-1) for the period 1990-2000 and 0.14% yr(-1) for the period 2000-2010. West Africa and Madagascar exhibit a much higher deforestation rate than the Congo Basin, for example, three times higher for West Africa and nine times higher for Madagascar. Analysis of variance over the Congo Basin is then used to show that expanding agriculture and increasing fuelwood demands are key drivers of deforestation in the region, whereas well-controlled timber exploitation programmes have little or no direct influence on forest-cover reduction at present. Rural and urban population concentrations and fluxes are also identified as strong underlying causes of deforestation in this study. Source

Jager-Waldau A.,European Commission - Joint Research Center Ispra
Solar Energy Materials and Solar Cells | Year: 2011

This paper gives an overview of the main research directions in chalcopyrite material research and the application of results for the improvement and fabrication of solar cells. So far the copper indium gallium sulphur selenide material family is the base for the highest efficiency thin-film solar cells and the most advanced in terms of actual commercialisation. The transfer of research results into actual production from its early stage and the development of the chalcopyrite thin-film solar cell industry are sketched. The last part of the review shortly describes a number of current industrial players involved in the manufacturing of chalcopyrite solar cells. © 2011 Elsevier B.V. All rights reserved. All rights reserved. Source

Tasdemir K.,European Commission - Joint Research Center Ispra
Pattern Recognition | Year: 2012

Spectral partitioning, recently popular for unsupervised clustering, is infeasible for large datasets due to its computational complexity and memory requirement. Therefore, approximate spectral clustering of data representatives (selected by various sampling methods) was used. Alternatively, we propose to use neural networks (self-organizing maps and neural gas), which are shown successful in quantization with small distortion, as preliminary sampling for approximate spectral clustering (ASC). We show that they usually outperform k-means sampling (which was shown superior to various sampling methods), in terms of clustering accuracy obtained by ASC. More importantly, for quantization based ASC, we introduce a local density-based similarity measure constructed without any user-set parameter which achieves accuracies superior to the accuracies of commonly used distance based similarity. © 2012 Elsevier Ltd. All rights reserved. Source

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