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Robust decision making, a growing approach to infrastructure planning under climate change uncertainty, aims to evaluate infrastructure performance across a wide range of possible conditions and identify the most robust strategies and designs. Robust decision making seeks to find potential weaknesses in systems in order to gird these through a combination of policy, infrastructure, and, in some cases, resilient or recovery strategies. A system can be explored by simulating many combinations of uncertain climatic and economic parameters; statistical clustering can identify parameter thresholds that lead to unacceptable performance. Often, however, uncertain variables are correlated, complicating the robustness analysis and casting doubt upon the thresholds identified. Here, we evaluate the impact of ordinary, hidden correlations in uncertainty parameters that drive simulation in robust decision making. We induced correlations between temperature and key climatic and economic parameters. We tested correlations of 0%, 30%, 60%, and 90% between temperature and the absolute value of precipitation, coefficient of variation, and downward surface solar radiation, and negative correlations between temperature and net variable benefit and the discount rate. We used a calibrated simulation model of a dam system regulating Lake Tana, Ethiopia, to compute the agricultural supply and net present value of the reservoirs. As the correlation strength increased, the results converged in a smaller region. We found that strong correlations depressed robustness scores of lower-performing alternatives and conversely increased results of the higher-performing alternatives. As the correlations increased in favorable alternatives, the failure thresholds became more extreme, speciously suggesting that only intense changes would result in poor performance. This overall analysis highlights the degree to which correlations of an interconnected climatic and economic system can impact outcomes of robust decision making and suggests methods to avoid confounding results.

  相似文献   
494.
Underground coal gasification (UCG) is an advancing technology that is receiving considerable global attention as an economic and environmentally friendly alternative for exploitation of coal deposits. UCG has the potential to decrease greenhouse gas emissions (GHG) during the development and utilization of coal resources. In this paper, the life cycle of UCG from in situ coal gasification to utilization for electricity generation is analyzed and compared with coal extraction through conventional coal mining and utilization in power plants. Four life cycle assessment models have been developed and analyzed to compare (greenhouse gas) GHG emissions of coal mining, coal gasification and power generation through conventional pulverized coal fired power plants (PCC), supercritical coal fired (SCPC) power plants, integrated gasification combined cycle plants for coal (Coal-IGCC), and combined cycle gas turbine plants for UCG (UCG-CCGT). The analysis shows that UCG is comparable to these latest technologies and in fact, the GHG emissions from UCG are about 28 % less than the conventional PCC plant. When combined with the economic superiority, UCG has a clear advantage over competing technologies. The comparison also shows that there is considerable reduction in the GHG emissions with the development of technology and improvements in generation efficiencies.  相似文献   
495.
A new modeling effort exploring the opportunities, constraints, and interactions between mitigation and adaptation at regional scale is utilizing stakeholder engagement in an innovative approach to guide model development and demonstration, including uncertainty characterization, to effectively inform regional decision making. This project, the integrated Regional Earth System Model (iRESM), employs structured stakeholder interactions and literature reviews to identify the most relevant adaptation and mitigation alternatives and decision criteria for each regional application of the framework. The information is used to identify important model capabilities and to provide a focus for numerical experiments. This paper presents the stakeholder research results from the first iRESM pilot region. The pilot region includes the Great Lakes Basin in the Midwest portion of the United States as well as other contiguous states. This geographic area (14 states in total) permits cohesive modeling of hydrologic systems while also providing strong gradients in climate, demography, land cover/land use, and energy supply and demand. The results from the stakeholder research indicate that, for this region, iRESM should prioritize addressing adaptation alternatives in the water resources, urban infrastructure, and agriculture sectors, including water conservation, expanded water quality monitoring, altered reservoir releases, lowered water intakes, urban infrastructure upgrades, increased electric power reserves in urban areas, and land use management/crop selection changes. For mitigation in this region, the stakeholder research implies that iRESM should focus on policies affecting the penetration of renewable energy technologies, and the costs and effectiveness of energy efficiency, bioenergy production, wind energy, and carbon capture and sequestration.  相似文献   
496.
Indentifying common priorities in shared natural resource systems constitutes an important platform for implementing adaptation and a major step in sharing a common responsibility in addressing climate change. Predominated by discourses on REDD + (Reduced Emissions from Deforestation and Forest Degradation and conservation, sustainable management of forests and enhancement of forest carbon stocks in developing countries) with little emphasis on adaptation there is a risk of lack of policy measures in addressing climate change in the Congo Basin. Forest products and ecosystem services provide security portfolios for the predominantly rural communities, and play major roles in national development programmes in both revenue and employment opportunities. Thus, raising the profile of forests in the policy arena especially in the twin roles of addressing climate change in mitigation and adaptation and achieving resilient development is crucial. Within the framework of the Congo Basin Forests and Climate Change Adaptation project (COFCCA) project, science policy dialogue was conducted to identify and prioritize forest based sectors vulnerable to climate change but important to household livelihoods and national development. The goal of the prioritization process was for the development of intervention in forest as measures for climate change adaptation in Central Africa. Participants constituted a wide range of stakeholders (government, Non Governmental Organizations, research institutions, universities, community leaders, private sectors etc.) as representatives from three countries directly involved in the project: Cameroon, Central African Republic and Democratic Republic of Congo. Building on national priorities, four forest related sectors were identified as common priorities at the regional level for focus on climate change adaptation. These sectors included: (1) energy with emphasis on fuel wood and Charcoal; (2) Water principally quality, quantity, accessibility, etc.; (3) Food with emphasis on Non Timber Forest Products, and (4) Health linked to healthcare products (medicinal plants). Using these prioritized sectors, the project focused on addressing the impacts of climate change on local communities and the development of adaptation strategies in the three pilot countries of the Congo Basin region. The four sectors constitute the key for development in the region and equally considered as priority sectors in the poverty reduction papers. Focused research on these sectors can help to inject the role of forests in national and local development and their potentials contributions to climate change adaptation in national and public discourses. Mainstreaming forest for climate change adaptation into national development planning is the key to improve policy coherence and effectiveness in forest management in the region.  相似文献   
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The fungicide vinclozolin and insecticide λ-cyhalothrin are widely used to control canola (Brassica spp.) diseases and insect pests, respectively, in Canada. We investigated non-target effects of these pesticides, applied at recommended rates, on soil microbial biomass, functional bacterial diversity and functional community structure of soil bacteria (by evaluating patterns of C substrate utilization) in canola rhizosphere and bulk soil at three locations in Alberta from 2002 to 2004. Experimental treatments were (a) untreated control, (b) vinclozolin fungicide foliar application, (c) λ-cyhalothrin insecticide foliar application, and (d) vinclozolin and λ-cyhalothrin applications. No significant pesticide effects on soil microbial biomass or functional bacterial diversity were observed, but the functional structures of soil bacteria were altered. In 1 of 12 cases, the control treatment had a different soil bacterial community structure from the 3 pesticide treatments. The fungicide treatment had different bacterial community structures from the control or insecticide treatments in 3 of 12 cases, the insecticide treatment had different community structures from the control or fungicide treatments in 4 of 12 cases, and the combined fungicide and insecticide treatment had different community structures from the other treatments in 3 of 12 cases. Therefore, evaluating soil bacterial functional structures revealed pesticide effects that were not detected when bacterial diversity or microbial biomass were measured in canola rhizosphere or bulk soil.  相似文献   
499.
A European scale network was established in 2006 as part of the NitroEurope Integrated Project to infer reactive nitrogen (Nr) dry deposition fluxes, based on low-cost sampling of gaseous and aerosol species and inferential modelling. The network provides monthly measurements of NH3, NH4+, HNO3 and NO3, as well as SO2, SO42−, HCl, Cl and base cations at 58 sites. Measurements are made with an established low-cost denuder methodology (DELTA) as a basis to: (1) examine temporal trends and spatial patterns across Europe, (2) improve and calibrate inferential modelling techniques to estimate exchange of Nr species, (3) provide best estimates of atmospheric dry N deposition, and (4) permit an analysis of net GHG exchange in relation to atmospheric and agricultural N inputs at the European scale. Responsibility for measurements is shared among seven European laboratories. An inter-comparison of the DELTA implementation by 6 laboratories at 4 test sites (Montelibretti, Italy; Braunschweig, Germany; Paterna, Spain and Auchencorth, UK) from July to October 2006 provided training for the laboratories and showed that good agreement was achieved in different climatic conditions (87% of laboratory site-means within 20% of the inter-laboratory median). Results obtained from the first year of measurements show substantial spatial variability in atmospheric Nr concentrations, illustrating the major local (NH3) and regional (HNO3, NO3, and NH4+) differences in Nr concentrations. These results provide the basis to develop future estimates of site-based Nr dry deposition fluxes across Europe, and highlight the role of NH3, largely of agricultural origin, which was the largest single constituent and will dominate dry Nr fluxes at most sites.  相似文献   
500.
The aim of this study was to investigate the effect of relative humidity (RH) and temperature on norovirus (NoV) persistence as infectious particles on food-contact surfaces such as stainless steel and polyvinyl chloride (PVC). For this purpose, a new method combining enzymatic digestion with molecular beacon-based NASBA targeting the ORF1-ORF2 domain was developed to discriminate between infectious and noninfectious NoV. Stainless steel and PVC disks were contaminated with known amounts of human NoV and kept for 56 days at 7 and 20°C at high (86% ± 4%) and low (30% ± 10%) RH. NoV retained its putative infectivity for 56 days on PVC and for 49 days on stainless steel at 7°C and for 7 and 28 days, respectively, at low and high RH at 20°C on both tested surfaces. These results confirm that NoV persists in an infective state on inert surfaces for long periods of time and consequently may cause illness. The new molecular approach to detecting infectious NoV on inert surfaces may provide valuable information for evaluating environmental surface decontamination strategies.  相似文献   
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