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61.
Michel Colombier 《Climate Policy》2013,13(4):453-473
What are relevant urban development investment strategies for improving building energy efficiency (BEE) and decarbonizing the urban district heating supply in rapidly urbanizing China? Different trajectories of BEE and energy supply technologies are compared in the urban context in a northern Chinese city. Vigorous improvement of BEE will significantly enhance the prospective financial capacity to facilitate deployment of backstop technologies (e.g. carbon capture and storage) in order to decarbonize the energy supply and achieve the long-term targets of low-carbon buildings. Carbon finance instruments should be used to facilitate public policy to accompany the necessary transition in the urban development process. The government-run efficiency procurement scheme will overcome the problem of insufficient incentive and high transaction costs associated with individual Clean Development Mechanism projects. Appropriate investment strategies (allocation of financial resources over the time frame) will allow local governments to harness the large potentials of carbon emissions mitigation while minimizing the risk of long-term technical lock-in in the built environment in Chinese cities. 相似文献
62.
63.
The organizational separation of management and other quaternary activities from production operations in American manufacturing has resulted in a divergent pattern of production and headquarter locations. We examine the external control relationships that arise from this separation between headquarter location and branch plant operations in nonmetropolitan Kentucky. Although corporate headquarters have diffused to the Sunbelt, no shift was found in the corporate control of branch plants in Kentucky. Nonmetropolitan manufacturing in Kentucky was oriented toward the metropolitan centers of the traditional manufacturing belt rather than the newer corporate centers of the South. Also control relationships are more likely to be local among smaller factories. Large plants having more autonomy in production or producing finished goods were more likely to be owned by a distant firm located in a large SMSA. 相似文献
64.
We suggest the method to calculate the natural component of the external loads due to organic matter and biogenic elements on the unexplored lakes using the removal rate moduli for these elements, and indices of the lakes’ specific catchments. The schematic map has been generated for the distribution of natural moduli of removal on the catchment of the Gulf of Finland. We calculated the external natural loads for 94 lakes in landscapes with a high percentage of lakes. 相似文献
65.
To assess the potential impacts of the US withdrawal from the Paris Agreement, this study applied GCAM-TU (an updated version of the Global Change Assessment Model) to simulate global and regional emission pathways of energy-related CO2, which show that US emissions in 2100 would reduce to ?2.4?Gt, ?0.7?Gt and ?0.2?Gt under scenarios of RCP2.6, RCP3.7 and RCP4.5, respectively. Two unfavourable policy scenarios were designed, assuming a temporary delay and a complete stop for US mitigation actions after 2015. Simulations by the Model for the Assessment of Greenhouse-gas Induced Climate Change (MAGICC) indicate that the temperature increase by 2100 would rise by 0.081°C–0.161°C compared to the three original RCPs (Representative Concentration Pathways) if US emissions were kept at their 2015 levels until 2100. The probability of staying below 2°C would decrease by 6–9% even if the US resumes mitigation efforts for achieving its Nationally Determined Contribution (NDC) target after 2025. It is estimated by GCAM-TU that, without US participation, increased reduction efforts are required for the rest of the world, including developing countries, in order to achieve the 2°C goal, resulting in 18% higher global cumulative mitigation costs from 2015 to 2100.Key policy insights
President Trump’s climate policies, including planned withdrawal from the Paris Agreement, cast a shadow on international climate actions, and would lower the likelihood of achieving the 2°C target.
To meet the 2°C target without the US means increased reduction efforts and mitigation costs for the rest of the world, and considerable economic burdens for major developing areas.
Active state-, city- and enterprise-level powers should be supported to keep the emission reduction gap from further widening even with reduced mitigation efforts from the US federal government.
66.
Sylvie Charbit Masa Kageyama Didier Roche Catherine Ritz Gilles Ramstein 《Global and Planetary Change》2005,48(4):1887
A coupling procedure between a climate model of intermediate complexity (CLIMBER-2.3) and a 3-dimensional thermo-mechanical ice-sheet model (GREMLINS) has been elaborated. The resulting coupled model describes the evolution of atmosphere, ocean, biosphere, cryosphere and their mutual interactions. It is used to perform several simulations of the Last Deglaciation period to identify the physical mechanisms at the origin of the deglaciation process. Our baseline experiment, forced by insolation and atmospheric CO2, produces almost complete deglaciation of past northern hemisphere continental ice sheets, although ice remains over the Cordilleran region at the end of the simulation and also in Alaska and Eastern Siberia. Results clearly demonstrate that, in this study, the melting of the North American ice sheet is critically dependent on the deglaciation of Fennoscandia through processes involving switches of the thermohaline circulation from a glacial mode to a modern one and associated warming of the northern hemisphere. A set of sensitivity experiments has been carried out to test the relative importance of both forcing factors and internal processes in the deglaciation mechanism. It appears that the deglaciation is primarily driven by insolation. However, the atmospheric CO2 modulates the timing of the melting of the Fennoscandian ice sheet, and results relative to Laurentide illustrate the existence of threshold CO2 values, that can be translated in terms of critical temperature, below which the deglaciation is impeded. Finally, we show that the beginning of the deglaciation process of the Laurentide ice sheet may be influenced by the time at which the shift of the thermohaline circulation from one mode to the other occurs. 相似文献
67.
特色保护类村域农村居民点空间重构探析 总被引:1,自引:0,他引:1
快速城镇化进程中中国乡村聚落空间面临剧烈分化和重组,农村居民点空间重构有利于乡村转型发展。论文基于系统理论,梳理了特色村落农村居民点空间系统形成机制,提出“遵循有序性—延续精神性—落脚物质性”的重构框架,并以贵州省江口县坝梅村为例,选用规模指数、基因分析及空间分析等方法解译了村域居民点系统内、外部特征,提出重构模式。研究表明:① 行为主体、文化基因及民居建筑构成坝梅村居民点内部系统,并分别呈“多元主体行为诱发空间变化、文化基因丰富但延续较差、用地结构与功能多样化”的特征;② 坝梅村居民点系统外部特征体现在外部环境对居民点起约束和导向作用,表现为距离点状、线状基础设施及河流越近,村域居民点数量、规模越大;③ 基于特征认知和重构框架,按照“分区—分类”方法,划分了核心区、重点区、提升区和保育区4种治理区以及完好型、受损型、缺失型、失真型4类民居提升类型,并提出了自组织和他组织2种模式下的居民点空间重构策略,为推动特色村落空间治理与转型提供参考。 相似文献
68.
旅游生态环境容量的经济学探讨 总被引:10,自引:4,他引:10
在总结旅游环境容量研究进展的基础上,提出了研究旅游环境容量意义及其概念体系,并就影响旅游环境容量的关键性因子-旅游生态环境容量进行了分析,运用经济学的理论和方法,提出了引起旅游生态环境容量的深层原因是外部不经济性,最后就为了实现资源环境的可持续发展,应该从法律、行政,经济、社会等角度对社会各利益加以协调,构建了有效的制度平台和相应的措施,使外部成本内部化,并提出了解决这些问题的具体对策和建议。 相似文献
69.
Ethanol Production: Energy and Economic Issues Related to U.S. and Brazilian Sugarcane 总被引:1,自引:0,他引:1
For a thorough and up-to-date evaluation of all the fossil energy costs of ethanol production from sugarcane in both the U.S.
and Brazil, every energy input in the biomass production and ultimate conversion process must be included. In this study,
more than 12 energy inputs in average U.S. and Brazilian sugarcane production are evaluated. Then in the fermentation/distillation
operation, nine more fossil fuel inputs are identified and included. Some energy and economic credits are given for the bagasse
to reduce the energy inputs required for steam and electricity. Based on all the fossil energy inputs in U.S. sugarcane conversion
process, a total of 1.12 kcal of ethanol is produced per 1 kcal of fossil energy expended. In Brazil a total of 1.38 kcal
of ethanol is produced per 1 kcal of fossil energy expended. Some pro-ethanol investigators have overlooked various energy
inputs in U.S. and Brazilian sugarcane production, including farm labor, farm machinery, processing machinery, and others.
In other studies, unrealistic low energy costs were attributed to such energy inputs, as nitrogen fertilizer, insecticides,
and herbicides. Both the U.S. and Brazil heavily subsidize ethanol production. Thus billions of dollars are invested in subsidies
and this significantly increases the costs to the consumers. The environmental costs associated with producing ethanol in
the U.S. and Brazil are significant but have been generally overlooked. The negative environmental impacts on the availability
of cropland and freshwater, as well as on air pollution and public health, have yet to be carefully assessed. These environmental
costs in terms of energy and economics should be calculated and included in future ethanol analyses so that sound assessments
can be made. In addition, the production of ethanol in the U.S. and Brazil further confirms that the mission of converting
biomass into ethanol will not replace oil. This mission is impossible. General concern has been expressed about taking food
crops to produce ethanol for burning in automobiles instead of using these crops as food for the many malnourished people
in the world. The World Health Organization reports that more than 3.7 billion humans are currently malnourished in the world—the
largest number of malnourished ever in history. 相似文献
70.
根据载波相位差分定位技术,利用待定点周边稳定的CORS站网形成的区域误差改正模型,对待定控制点观测数据的噪声进行自动剔除,对电离层、对流层和多路径进行差分改正,研发GNSS全自动解算软件,并利用广西卫星定位基准站与待定控制点的GNSS观测数据对软件进行测试。结果表明,GNSS全自动解算软件具有较好的内外符合精度,其解算的三维坐标精度满足D级以下等级控制点的要求,可为工程测量应用提供新的自动化解算方案。 相似文献