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241.
Co-integration theory has been employed in this paper and Granger causes are found between urbanization rate and GDP, between capital stock and GDP. Scenario analysis of GDP is performed using the GDP model established in the paper. The energy consumptions in Germany, Japan and other developed countries are analyzed and compared with the energy consumption in China. Environmental friendly scenario of energy demand and CO2 emissions for sustainable China has been formed based on the results of comparison. Under environmental friendly scenario, the primary energy consumption will be 4.31 billion ton coal equivalence (tee) and CO2 emissions will be 1.854 billion t-c in 2050; energy per capital will be 3.06 tee that is 1.8 times of energy consumed in 2005 in China and 51% of consumed energy per capital in Japan in 2003. In 2050, the energy requirement of unit GDP will be 20% lower than that of Germany in 2003, but will be still 37% higher than that in Japan in 2003. It is certain that to fulfill the environmental friendly Scenario of energy demand and CO2 emissions is a difficult task and it needs long term efforts of the whole society, not only in production sectors but also in service and household sectors,  相似文献   
242.
山东省水泥行业CO_2减排关键技术的实施分析   总被引:1,自引:1,他引:0  
由于社会对水泥需求的不断增长,多年来山东省水泥工业一直处于快速发展时期。作为国民经济的基础工业同时也是高耗能行业,山东省水泥行业面临着巨大的CO2减排压力。同时,技术自身的先进性决定了其相应的减排潜力,而减排效果的实现程度则取决于技术的推广度。在技术的推广过程中,其减排潜力、减排成本以及相关的政策支持都是关键性的影响因素,针对技术实施障碍进行深入的分析和探讨对实际减排效果的预测具有重要的意义。本研究利用长期能源替代规划系统软件建立了LEAP-Shandong Cement模型,对山东省水泥行业的CO2排放量及相应的减排潜力进行了模拟评估。到2020年,相对于基准情景,政策情景和技术情景下的减排潜力分别为8.2%和15.6%。山东省水泥行业实现减排主要依靠窑型的替代和相应技术的进步,其中余热发电技术改进为近期的重点减排技术,在水泥行业减排兼具显著的环境、经济和社会效益。  相似文献   
243.
Projection of hazard changes in climate extremes is critical to assessing the potential impacts of climate change on human and natural systems. Using simulations of providing regional climates for impacts studies, five indicators (rainstorm days, maximum 3-day precipitation, elevation, gradient and distance from river or lake) were selected to project the spatial patterns of flood hazard over Yangtze River Basin for the baseline period (1961– 1990) and future (2011–2100) under SRES B2 scenario. The results ...  相似文献   
244.
Transportation is a sector with high energy consumption as well as high emissions. Generally speaking, economic growth will inevitably lead to the increase of travel demand and vehicle population, which in turn results into the augmentation of environmental and social costs. For metropolis like Beijing under rapid development, there exist various possibilities and options for transport development policy instruments. But there is no guarantee that they will be suitable for Beijing, although they are effective in their local places. This article assesses what kind of policy can most effectively improve the traffic conditions in Beijing in the future. After literature reviews on the practices of foreign policy and we established several feasible scenarios. Then, we used the Long Range Energy Alternatives Planning System (LREAP) analyzed their corresponding results of reduced energy consumption and emissions. Finally, by simulating and computing the realistic Beijing transportation scenarios, this paper scientifically assesses what kind of policy can most effectively improve the traffic condition in Beijing in the coming decade.  相似文献   
245.
大空间建筑由于其功能、结构上的特殊性,使得现有的消防规范不能满足其防火要求,特别是针对大空间建筑的防排烟设计就更为不适用。性能化设计方法是目前防火领域最先进的技术,水喷淋系统作为大空间建筑原有的消防设施其对火灾烟气输运的影响,已作为一项重要的性能参考指标。笔者从数值模拟的角度出发,利用流体动力学软件FDS,研究有无喷淋情况下火源功率能量传递及羽流烟气的输运过程。通过对两种火灾场景下火羽流温度、地面传导热通量及辐射热通量的对比分析,探讨了火羽流流场分布形式,为大空间建筑的防排烟设计提供有力参考。  相似文献   
246.
石化行业作为中国八大典型高碳排放产业之一,也是碳市场参与的重要行业.在国家2020年碳排放强度目标的约束下,客观评价其行业减碳的压力,对于政府部门科学制定各个行业碳排放配额的分配方案具有重要支撑作用.同时,亦对于通过低碳转型升级实现行业的可持续发展和支撑国家的工业减排目标具有理论和现实意义.本文针对石化行业9个子部门,结合我国经济发展的总体背景和趋势以及石化行业的相关数据,以2010年为基准情景,在2020年国家碳排放强度分别下降45%和50%的减排约束目标下,构建了一个动态CGE模型——PCCGE,借助GAMS软件模拟分析,预测了到2020年国家和石化行业经济总量、能源消费结构和碳排放量及碳强度等的变化趋势.研究结果表明,相比基准情景,在45%、50%的碳强度减排目标下,国家和石化行业的经济增长、能源消费结构和碳排放强度等指标分别受到一定程度影响,其中,50%的减排目标对国家整体经济增速影响更为明显;对煤炭、石油这两种高碳能源的需求产生了较显著的约束效应;相比国家45%-50%的低碳发展目标,石化行业减碳承受压力达到60.63%至64.78%,面临着艰巨的减排任务与挑战.最后,文章结合低碳市场化背景提出了如下建议:科学预测典型离碳行业的减碳潜力,谨慎应对石化等行业企业参与碳市场交易过程中碳配额指标的制定与分配;充分利用技术创新和能源结构调整等战略,提高可再生能源的使用规模,促进能源消耗结构的优化和调整;构建石化行业节能低碳技术产学研协同创新体系,解决共性节能技术瓶颈;实施石化行业企业低碳发展战略,建设完善碳排放管理体系是行业节能减碳的重要手段.  相似文献   
247.
The Upper Mississippi River Basin and Ohio‐Tennessee River Basin comprise the majority of the United States Corn Belt region, resulting in degraded Mississippi River and Gulf of Mexico water quality. To address the water quality implications of increased biofuel production, biofuel scenarios were tested with a Soil and Water Assessment Tool (SWAT) model revision featuring improved biofuel crop representation. Scenarios included corn stover removal and the inclusion of two perennial bioenergy crops, switchgrass and Miscanthus, grown on marginal lands (slopes >2% and erosion rates >2 t/ha) and nonmarginal lands. The SWAT model estimates show water quality is not very sensitive to stover removal. The perennial bioenergy crops reduce simulated sediment, nitrogen (N), and phosphorus (P) yields by up to 60%. Simulated sediment and P reductions in marginal lands were generally twice that occurring in the nonmarginal lands. The highest unit area reductions of N occurred in the less sloping tile‐drained lands. Productivity showed corn grain yield was independent from stover removal, while yields of the two perennial bioenergy crops were similar in the marginal and nonmarginal lands. The results suggest planning for biofuel production in the Corn Belt could include the removal of stover in productive corn areas, and the planting of perennial bioenergy crops in marginal land and in low‐sloped tile‐drained areas characterized by high N pollution. Editor's note : This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series.  相似文献   
248.
以火法炼铜全生命周期过程为研究对象,采用生命周期评价(LCA)方法,定量评价不同熔炼工艺生产铜过程的能源消耗和温室气体排放,并应用情景分析法,对2020年我国火法炼铜不同工艺技术结构下的能耗与碳排放强度进行比较,旨在为铜冶炼行业的结构调整与优化升级提供决策支持。结果表明,基于鼓风熔炼、闪速熔炼和熔池熔炼工艺的火法生产铜过程的能耗分别为147.80×103,96.68×103,104.20×103MJ;其碳排放强度分别为15.32×103,8.99×103,10.01×103kg CO2当量。设定的4种情景的能耗分别为111.60×103,103.37×103,101.19×103,99.69×103MJ;其碳排放强度分别为10.87×103,9.87×103,9.60×103,9.40×103kg CO2当量。由此可知,传统工艺鼓风炉熔炼较闪速熔炼及熔池熔炼的能耗更高,且导致了更多的温室气体排放。因此,大力发展闪速熔炼及熔池熔炼技术对降低铜生命周期的能耗及碳排放具有重要意义,彻底淘汰传统熔炼工艺,推广先进熔炼技术是减少火法铜生产环境影响的迫切任务。  相似文献   
249.
应对气候变化的科学基础是摸清区域碳排放基本状况,对碳排放现状的梳理是探索环境改善路径的依据。探索低碳发展路径的核心在于减排政策选择,同时也是实现可持续发展的条件保障。京津冀协同发展背景下区域环境保护及大气污染治理成为研究热点,河北省资源环境容量与经济增长之间的矛盾日益凸显,生态文明、可持续发展的要求促使探明环境现状,研究节能减排低碳发展的创新机制。摸清河北省碳排放基本现状,探明能源需求和碳排放的演变规律,对河北省探索低碳发展路径具有实践意义。本文基于河北省全域的数据资料和实地调查,核算了河北省下辖11个地级市能源活动引起的碳排放,分析了2005-2013年碳排放的时空演化规律,以情景分析方法为基础,预测了河北省到2030年的碳排放状况。认为:第一,能源活动的碳排放量从研究时间尺度上来看,始终保持增长的趋势,且2009年以后增长更为显著;从空间尺度上来看,唐山市的排放始终是全省最高。第二,基于情景分析对河北省能源活动的碳排放可能状况进行预测。基准情景是排放量最高的情景;低碳情景下2025年前后碳排放量基本稳定;强化低碳情景下设定2030年回到2005年的排放水平上,人均碳排放量始终保持下降,2030年将与全国2012年的人均排放平均水平相当。  相似文献   
250.
Scientists, resource managers, and decision makers increasingly use knowledge coproduction to guide the stewardship of future landscapes under climate change. This process was applied in the California Central Valley (USA) to solve complex conservation problems, where managed wetlands and croplands are flooded between fall and spring to support some of the largest concentrations of shorebirds and waterfowl in the world. We coproduced scenario narratives, spatially explicit flooded waterbird habitat models, data products, and new knowledge about climate adaptation potential. We documented our coproduction process, and using the coproduced models, we determined when and where management actions make a difference and when climate overrides these actions. The outcomes of this process provide lessons learned on how to cocreate usable information and how to increase climate adaptive capacity in a highly managed landscape. Actions to restore wetlands and prioritize their water supply created habitat outcomes resilient to climate change impacts particularly in March, when habitat was most limited; land protection combined with management can increase the ecosystem's resilience to climate change; and uptake and use of this information was influenced by the roles of different stakeholders, rapidly changing water policies, discrepancies in decision-making time frames, and immediate crises of extreme drought. Although a broad stakeholder group contributed knowledge to scenario narratives and model development, to coproduce usable information, data products were tailored to a small set of decision contexts, leading to fewer stakeholder participants over time. A boundary organization convened stakeholders across a large landscape, and early adopters helped build legitimacy. Yet, broadscale use of climate adaptation knowledge depends on state and local policies, engagement with decision makers that have legislative and budgetary authority, and the capacity to fit data products to specific decision needs.  相似文献   
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