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991.
992.
Waage, Marc D. and Laurna Kaatz, 2011. Nonstationary Water Planning: An Overview of Several Promising Planning Methods. Journal of the American Water Resources Association (JAWRA) 47(3):535‐540. DOI: 10.1111/j.1752‐1688.2011.00547.x Abstract: Climate change is challenging the way water utilities plan for the future. Observed warming and climate model projections now call into question the stability of future water quantity and quality. As water utilities cope with preparing for the large range of possible changes in climate and the resulting impacts on their water systems, many are searching for planning techniques to help them consider multiple possible conditions to better prepare for a different, more uncertain, future. Many utilities need these techniques because they cannot afford to delay significant decisions while waiting for scientific improvements to narrow the range of potential climate change impacts. Several promising methods are being tested in water utility planning and presented here for other water utilities to consider. The methods include traditional scenario planning, classic decision making, robust decision making, real options, and portfolio planning. Unfortunately, for utilities vulnerable to climate change impacts, there is no one‐size‐fits‐all planning solution. Every planning process must be tailored to the needs and capabilities of the individual utility.  相似文献   
993.
Brown, Casey, William Werick, Wendy Leger, and David Fay, 2011. A Decision‐Analytic Approach to Managing Climate Risks: Application to the Upper Great Lakes. Journal of the American Water Resources Association (JAWRA) 47(3):524‐534. DOI: 10.1111/j.1752‐1688.2011.00552.x Abstract: In this paper, we present a risk analysis and management process designed for use in water resources planning and management under climate change. The process incorporates climate information through a method called decision‐scaling, whereby information related to climate projections is tailored for use in a decision‐analytic framework. The climate risk management process begins with the identification of vulnerabilities by asking stakeholders and resource experts what water conditions they could cope with and which would require substantial policy or investment shifts. The identified vulnerabilities and thresholds are formalized with a water resources systems model that relates changes in the physical climate conditions to the performance metrics corresponding to vulnerabilities. The irreducible uncertainty of climate change projections is addressed through a dynamic management plan embedded within an adaptive management process. Implementation of the process is described as applied in the ongoing International Upper Great Lakes Study.  相似文献   
994.
以华北农牧交错带为切入点,选取晋北长城沿线大同市8个气象站点,利用线性趋势分析、5年滑动、M-K检验以及Thormthwaite模型,分析了近38年来大同市气候变化及其气候生产力的演变特征.结果表明:①近38年大同市气温呈现显著增加趋势,且在1994年发生突变.②降水量呈现不显著的减少趋势.③气候生产力呈现缓慢增加趋势,出现南部高于北部,东西方向上呈现由中心向四周递增.④暖湿气候的气候生产力呈现正距平,最适合作物生长;冷干气候的气候生产力呈现负距平,最不适合作物生长.现阶段气候暖干化趋势显著,因此研究气候变化对气候生产力有重要意义.  相似文献   
995.
A methodology for regional application of forest simulation models has been developed as part of an assessment of possible climate change impacts in the Federal state of Brandenburg (Germany). Here we report on the application of a forest gap model to analyse the impacts of climate change on species composition and productivity of natural and managed forests in Brandenburg using a statistical method for the development of climate scenarios. The forest model was linked to a GIS that includes soil and groundwater table maps, as well as gridded climate data with a resolution of 10 × 10 km and simulated a steady-state species composition which was classified into forest types based on the biomass distribution between species. Different climate scenarios were used to assess the sensitivity of species composition to climate change. The simulated forest distribution patterns for current climate were compared with a map of Potential Natural Vegetation (PNV) of Brandenburg.In order to analyse the possible consequences of climate change on forest management, we used forest inventory data to initialize the model with representative forest stands. Simulation experiments with two different management strategies indicated how forest management could respond to the projected impacts of climate change. The combination of regional analysis of natural forest dynamics under climate change with simulation experiments for managed forests outlines possible trends for the forest resources. The implications of the results are discussed, emphasizing the regional differences in environmental risks and the adaptation potentials of forestry in Brandenburg.  相似文献   
996.
The potential ecological impact of ongoing climate change has been much discussed. High mountain ecosystems were identified early on as potentially very sensitive areas. Scenarios of upward species movement and vegetation shift are commonly discussed in the literature. Mountains being characteristically conic in shape, impact scenarios usually assume that a smaller surface area will be available as species move up. However, as the frequency distribution of additional physiographic factors (e.g., slope angle) changes with increasing elevation (e.g., with few gentle slopes available at higher elevation), species migrating upslope may encounter increasingly unsuitable conditions. As a result, many species could suffer severe reduction of their habitat surface, which could in turn affect patterns of biodiversity. In this paper, results from static plant distribution modeling are used to derive climate change impact scenarios in a high mountain environment. Models are adjusted with presence/absence of species. Environmental predictors used are: annual mean air temperature, slope, indices of topographic position, geology, rock cover, modeled permafrost and several indices of solar radiation and snow cover duration. Potential Habitat Distribution maps were drawn for 62 higher plant species, from which three separate climate change impact scenarios were derived. These scenarios show a great range of response, depending on the species and the degree of warming. Alpine species would be at greatest risk of local extinction, whereas species with a large elevation range would run the lowest risk. Limitations of the models and scenarios are further discussed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
997.
Adaptation in response to anthropogenic climate change seeks to maintain viability by maximising benefits and minimising losses. It is necessary because some climatic change is now inevitable, despite the international focus on mitigation measures. Indeed, the measures agreed at Kyoto would by themselves result in only a small reduction in the climate changes to be expected over the next century.Discussion of the expected changes and possible impacts leads to the following conclusions regarding climate change scenarios in relation to impacts and adaptation: Climate change in the foreseeable future will not be some new stable "equilibrium" climate, but rather an ongoing "transient" process; Climate change predictions relevant to impacts on most sectors and ecosystems are still highly uncertain; There is a need for a greater focus on developing countries and tropical regions, and on relevant key variables, including the magnitude and frequency of extreme events; The focus should shift from single predictions, or extreme ranges of uncertainty, to risk assessment; Thresholds critical to impacted sectors and ecosystems should be identified, and expressed as functions of climatic variables; Planned adaptations will be necessary to cope with multiple stresses, including those due to non-climatic changes; A major task of adaptation science is to identify the limits of adaptation, i.e., to identify "dangerous levels of greenhouse gases" beyond which adaptation becomes impractical or prohibitively expensive.  相似文献   
998.
A standard framework is presented as an underlying model for the discounting debate. Views and proposals for the techniques and rates of discounting are assessed. Alternative modeling frameworks for studying intergenerational equity issues are evaluated with the result that the basic insights they provide do not differ very much. Results from model experiments involving different discount rate proposals show that fudging the discount rate does not lead to efficient climate policy. Three major clusters of opinions are identified regarding the applicability of cost-benefit analysis to the climate change problem and the appropriate discount rate to use. It is concluded that under some very special circumstances the cost-benefit rule should be abandoned and cost-effective strategies implying standard discount rates should be sought to reach clearly defined and justified environmental targets. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
999.
Human induced climate change is one of the single most significant indicators that human society is not pursuing a sustainable trajectory. Managing the risks requires a major transformation of the way energy needs are met. Such a transformation includes changes in the production and consumption system and the incentive structure that shapes this system. The major driving force for transformation is the public concern about the environmental impact of the present fossil fuel based energy system. We may expect that energy producers, encouraged by governments, NGOs and consumer preferences will be responding to these concerns and expectations sooner or later. In fact a number of major international energy companies are presently adjusting their strategies to the needs and concerns of the public. A mix of measures including energy efficiency, a switch to natural gas, major investments in low carbon and renewable energy technologies and underground storage of carbon are elements of such new strategies. Consumers in a number of OECD countries have expressed their willingness to pay more for energy, provided it is green and clean. NGOs continue to put pressure on governments to deal with the climate problem. The challenge for governments is to develop an institutional framework that helps the producers and consumers to go through a transformation of the energy system. As different groups in society are likely to support different strategies, this paper suggests that a pluralistic policy approach including efficiency standards, renewable energy portfolio standards, carbon taxes, and the introduction of a system of tradable emission permits is the most promising approach for a transformation towards a low carbon energy economy. Research can support a transformation of the energy system by exploring the various transformation scenarios. Such research should take a multi-disciplinary approach, it should focus on the energy system as a whole, including production, consumption and the incentive structure that shapes the interaction between the two and it should be international in scope. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
1000.
Long-term variability in the North Atlantic Oscillation (NAO) and the Atlantic thermohaline ocean circulation (THC) are both shaping the European climate on time scales of decades and longer. Possible linear and non-linear changes in the characteristics of these natural climate modes due to global warming are an important source of uncertainty in long-term regional projections of future climate changes. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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