2,528 research outputs found
Environmental screening tools for assessment of infrastructure plans based on biodiversity preservation and global warming (PEIT, Spain).
Most Strategic Environmental Assessment (SEA) research has been concerned with SEA as a procedure, and there have been relatively few developments and tests of analytical methodologies. The first stage of the SEA is the ‘screening’, which is the process whereby a decision is taken on whether or not SEA is required for a particular programme or plan. The effectiveness of screening and SEA procedures will depend on how well the assessment fits into the planning from the early stages of the decision-making process. However, it is difficult to prepare the environmental screening for an infrastructure plan involving a whole country. To be useful, such methodologies must be fast and simple. We have developed two screening tools which would make it possible to estimate promptly the overall impact an infrastructure plan might have on biodiversity and global warming for a whole country, in order to generate planning alternatives, and to determine whether or not SEA is required for a particular infrastructure plan
On Security and reliability using cooperative transmissions in sensor networks
Cooperative transmissions have received recent attention and research papers have demonstrated their benefits for wireless networks. Such benefits include improving the reliability of links through diversity and/or increasing the reach of a link compared to a single transmitter transmitting to a single receiver (single-input single-output or SISO). In one form of cooperative transmissions, multiple nodes can act as virtual antenna elements and provide diversity gain or range improvement using space-time coding. In a multi-hop ad hoc or sensor network, a source node can make use of its neighbors as relays with itself to reach an intermediate node with greater reliability or at a larger distance than otherwise possible. The intermediate node will use its neighbors in a similar manner and this process continues till the destination is reached. Thus, for the same reliability of a link as SISO, the number of hops between a source and destination may be reduced using cooperative transmissions as each hop spans a larger distance. However, the presence of ma-licious or compromised nodes in the network impacts the benefits obtained with cooperative transmissions. Using more relays can increase the reach of a link, but if one or more relays are malicious, the transmission may fail. However, the relationships between the number of relays, the number of hops, and success probabilities are not trivial to determine. In this paper, we analyze this problem to understand the conditions under which cooperative transmissions fare better or worse than SISO transmissions. We take into consideration additional parameters such as the path-loss exponent and provide a framework that allows us to evaluate the conditions when cooperative transmissions are better than SISO transmissions. This analysis provides insights that can be employed before resorting to simulations or experimentation. © Springer Science+Business Media, LLC 2012
Impact of land use on urban mobility patterns, emissions and air quality in a Portuguese medium-sized city
The main objective of this work was to evaluate the impact of urban development trends in mobility patterns of a medium sized Portuguese city and air quality consequences, using a sequential modeling process, comprising i) land use and transportation, TRANUS model; ii) road traffic air pollutants emissions, TREM model and; iii) air quality, TAPM model. This integrated methodology was applied to a medium sized Portuguese city. In order to evaluate the implementation of the methodology, a preliminary study was performed, which consisted on the comparison of modeled mobility patterns and CO and PM(10) concentrations with measured data used in the definition of the current scenario. The comparison between modeled and monitored mobility patterns at the morning peak hour for a weekday showed an RMSE of 31%. Regarding CO concentrations, an underestimation of the modeled results was observed. Nevertheless, the modeled PM(10) concentrations were consistent with the monitored data. Overall, the results showed a reasonable consistency of the modeled data, which allowed the use of the integrated modeling system for the study scenarios. The future scenarios consisted on the definition of different mobility patterns and vehicle technology characteristics, according to two main developing trends: (1) "car pooling" scenario, which imposes a mean occupancy rate of 3 passengers by vehicle and (2) the "Euro 6" scenario, which establishes that all vehicles accomplish at least the Euro 6 standard technology. Reductions of 54% and 83% for CO, 44% and 95% for PM(10), 44% and 87% for VOC and 44% and 79% for NO(x) emissions were observed in scenarios 1 and 2, respectively. Concerning air quality, a reduction of about 100 mug m(-3) of CO annual average concentration was observed in both scenarios. The results of PM(10) annual concentrations showed a reduction of 1.35 mug m(-3) and 2.7 mug m(-3) for scenarios 1 and 2 respectively
Using the NOAA Advanced Very High Resolution Radiometer to characterise temporal and spatial trends in water temperature of large European lakes
Lakes are major repositories of biodiversity, provide multiple ecosystem services and are widely recognised as key indicators of environmental change. However, studies of lake response to drivers of change at a pan-European scale are exceptionally rare. The need for such studies has been given renewed impetus by concerns over environmental change and because of international policies, such as the EU Water Framework Directive (WFD), which impose legal obligations to monitor the condition of European lakes towards sustainable systems with good ecological status. This has highlighted the need for methods that can be widely applied across large spatial and temporal scales and produce comparable results. Remote sensing promises much in terms of information provision, but the spatial transferability and temporal repeatability of methods and relationships observed at individual or regional case studies remains unproven at the continental scale. This study demonstrates that NOAA Advanced Very High Resolution Radiometer (AVHRR) thermal data are capable of producing highly accurate (R2 > 0.9) lake surface temperature (LST) estimates in lakes with variable hydromorphological characteristics and contrasting thermal regimes. Validation of the approach using archived AVHRR thermal data for Lake Geneva produced observations that were consistent with field data for equivalent time periods. This approach provides the basis for generalizing temporal and spatial trends in European lake surface temperature over several decades and confirms the potential of the full 30 year NOAA AVHRR archive to can provide AVHRR-derived LST estimates to help inform European policies on lake water quality.</p
The challenges of monitoring national climate policy: learning lessons from the EU
One of the most central and novel features of the new climate governance architecture emerging from the 2015 Paris Agreement is the transparency framework committing countries to provide, inter alia, regular progress reports on national pledges to address climate change. Many countries will rely on public policies to turn their pledges into action. This article focuses on the EU’s experience with monitoring national climate policies in order to understand the challenges that are likely to arise as the Paris Agreement is implemented around the world. To do so, the research employs – for the first time – comparative empirical data submitted by states to the EU’s monitoring system. Our findings reveal how the EU’s predominantly technical interpretation of four international reporting quality criteria – an approach borrowed from reporting on GHG fluxes – has constrained knowledge production and stymied debate on the performance of individual climate policies. Key obstacles to more in-depth reporting include not only political concerns over reporting burdens and costs, but also struggles over who determines the nature of climate policy monitoring, the perceived usefulness of reporting information, and the political control that policy knowledge inevitably generates. Given the post-Paris drive to achieve greater transparency, the EU’s experience offers a sobering reminder of the political and technical challenges associated with climate policy monitoring, challenges that are likely to bedevil the Paris Agreement for decades to come
Patriotic values for public goods: transnational trade-offs for biodiversity and ecosystem services?
The natural environment is central to human well-being through its role in ecosystem service (ES) provision. Managing ES often requires coordination across international borders. Although this may deliver greater conservation gains than countries acting alone, we do not know whether the public supports such an international approach. Using the same questionnaire in three countries, we quantified public preferences for ES in home countries and across international borders. In all three countries, the people were generally willing to pay for ES. However, our results show that there is a limit to the extent that environmental goods can be considered global. ES with a use element (habitat conservation, landscape preservation) attracted a patriotic premium, such that the people were willing to pay significantly more for locally delivered services. Supranational management of ES needs to be balanced against the preferences that people have for services delivered in their home countries
- …
