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31.
英国温室气体排放贸易制度的实践与评价   总被引:1,自引:0,他引:1  
温室气体排放贸易作为一种经济激励型的环境管理手段,对企业减少温室气体排放有成本效率作用。详细介绍了英国温室气体排放贸易制度框架,并对其政策的效果及存在的问题进行了评价。  相似文献   
32.
为了以数值试验手段定量地再现青藏高原地形对冬季东移大槽的影响,也同时讨论冬季亚洲不同高空环流形势下地形对东移槽影响的差别,本文使用我所6层有限区域格点模式,首先根据该模式对初始场的需要,也源于冬季亚洲地区高空流型的特点,构造了以基本斜压西风气流加高空西风急流,并在其上迭加正弦波槽扰动为主要特征的环境流场等的理想初始场及理想地形场。然后,根据不同流场成员和地形的组合,设计了13个数值模拟试验。接着,利用整层无辐散初始化方案,固定侧边界条件,对各试验积分4—5天,最后分析各试验中东移槽的行为。本研究第三部分的模拟试验结果的分析表明〔19〕,模式计算稳定,模拟结果合理,说明文中理想场的构造是协调的、合理的,也比较接近实际。侧边界条件及初始场的预处理也大体是合适的。  相似文献   
33.
中国近海大风极值计算方法研究   总被引:5,自引:0,他引:5  
阎俊岳  黄爱芬 《气象学报》1996,54(2):233-239
讨论了中国近海(渤、黄、东、南海)开阔洋面上求算不同重现期大风极值的资料和方法。在没有定点连续气象观测条件下,综合分析现有岛屿站观测、台风记录、船舶报告、数值模式计算风速,分别组成年大风极值序列,使用多种分布模型拟合大风序列,通过检验选定最佳取值。研究结果表明,在拟合各类大风序列时,三参数Weibull分布显示较强的适用性;而由波浪谱模式和台风风场模式计算风速组成的序列求取不同重现期大风极值,计算结果稳定,气候分布合理。  相似文献   
34.
基于原正交ECOM(Estuarine Coastal and Ocean Model)模式,把它改进为非正交曲线坐标系下模式,以较好地拟合河口海岸岸线的变化,有效提高局部空间分辨率,提高计算速度和精度;应用预估修正法提高模式的稳定性;扣除局域平均密度层结提高。坐标系下斜压压强梯度力的计算精度;采用Euler-Lagrange方法改进物质输运方程中的平流项计算方法。数值试验结果证明以上4种方法有效地提高了模式的计算精度。把改进的模式应用于长江河口、杭州湾及邻近海区,模拟结果与观测资料较为一致。改进后的模式可更好地应用于河口海岸的研究中。  相似文献   
35.
Abstract

Artificial neural network (ANN) models provide huge potential for simulating nonlinear behaviour of hydrological systems. However, the potential of ANN is yet to be fully exploited due to the problems associated with improving the model generalization performance. Generalization refers to the ability of a neural network to correctly process input data that have not been used for calibrating the neural network model. In the hydrological context, better generalization performance implies higher precision of forecasting. The primary objectives of this study are to explore new measures for improving the generalization performance of an ANN-based rainfall–runoff model, and to evaluate the applicability of the new measures. A modified neural network model (entitled goal programming (GP) neural network) for modelling the rainfall–runoff process has been developed, in which three enhancements are made as compared to the widely-used backpropagation (BP) network. The three enhancements are (a) explicit integration of hydrological prior knowledge into the neural network learning; (b) incorporation of a modified training objective function; and (c) reduction of network sensitivity to input errors. Seven watersheds across a range of climatic conditions and watershed areas in China were selected for examining the alternative networks. The results demonstrate that the GP consistently outperformed the BP both in the calibration and verification periods and three proposed measures yielded improvement of performance.  相似文献   
36.
Linking a cap-and-trade with an offset mechanism has many theoretical advantages: it reduces compliance costs, extends the price signal outside the cap-and-trade, and triggers technology transfer. However, it is feared that such linking will induce outsourcing of emissions reduction at a low price and undermine the price incentive in the cap-and-trade. The EU Emissions Trading Scheme (EU ETS) is the first full-scale example of a cap-and-trade system linked to project-based mechanisms such that offsets have effectively been used by industrial installations. This article is an ex post analysis of EU ETS data for the years 2008 and 2009, and the characteristics of the link and its efficiency are evaluated. Although offsets have been much used, their use is concentrated and not very intense or frequent, which allays the fear that offsets will flood the market. Although the majority of surrendered CERs effectively come from the largest and oldest projects, the credits surrendered are similar to those available on the market. Possible factors that contribute towards inefficiency are the rules for using offsets, transaction costs affecting the participation of small installations, awareness and openness to market-based instruments, and uncertainties regarding CERs offer and demand from other markets. However, the impact on EUA equilibrium price still needs to be quantified.  相似文献   
37.
The main incentives for Russia's and Ukraine's participation in the first commitment period of the Kyoto Protocol were its mechanisms. The opportunities that the anticipated post-2012 mechanisms will offer Russia and Ukraine are explored in light of the lessons from Joint Implementation (JI) and the Green Investment Scheme (GIS) during this first period. Four key factors that explain the success of these mechanisms are identified: the design of the mechanisms, the role of the private sector in their implementation, the coordination required, and the political will gained. Even though a weak rule of law, problems with policy implementation, and the ambiguous role of private-sector actors are not ‘make or break’ issues, they are likely to defer future mechanisms. Success and failure will, rather, hinge on the priority these factors are accorded by the top leadership. It is likely that simple mechanisms that only involve a few actors will be less complicated to set up and run than, for instance, emissions trading schemes (which require domestic burden sharing). Project-based options in which domestic actors have gained experience may be better suited. However, any lessons prior to the new mechanisms taking a clearer shape must be considered as preliminary.

Policy relevance

The Kyoto Protocol mechanisms, despite their problems, provided Russia and Ukraine with their main incentives for participation in the Protocol's first commitment period. As the chances that these countries will participate in the second commitment period seem slim, the opportunities that the anticipated post-2012 mechanisms will offer Russia and Ukraine are explored in light of the lessons from JI and GIS. The key factors that have determined the success and failure of these mechanisms are likely to be of relevance to future mechanisms. It is argued that – of the post-2012 options available – simple mechanisms with few actors involved should be chosen. Project-based options rather than emissions trading schemes may be more likely to succeed due to experience gained by domestic actors.  相似文献   
38.
《Climate Policy》2013,13(3):227-241
How effective is the EU Emissions Trading Scheme (EU ETS) in promoting emissions reduction for compliance with the Kyoto Protocol commitment? A theoretical benchmark is determined in order to assess the stringency of the ETS cap and to evaluate whether emissions allowances have been over-allocated. This analysis clarifies how the emissions reduction effort has been divided between ETS and non-ETS sectors, highlighting the extent to which Member States effectively rely on the ETS to comply with their Kyoto commitments. Finally, inefficiencies relating to the over-allocation of allowances are analysed; namely cross-subsidization from non-ETS to ETS sectors, national subsidies to the ETS sectors, and distortion of competition.  相似文献   
39.
《Climate Policy》2013,13(2):190-215
Until now, there has been little empirical evidence that EU Emissions Trading Scheme (ETS) transaction costs are incurred at firm level. The transaction costs (internal costs, capital costs, consultancy and trading costs) incurred by Irish firms under the EU ETS during its pilot phase (2005–2007) were measured and analysed. Evidence for the sources of transaction costs, their magnitude and the distribution of costs shows that these were mainly administrative in nature. Considerable variation in costs was found due to economies of scale, as the costs per tonne of CO2 were lower for participants with larger allocations. For the largest firms—accounting for over half the emissions—average transaction costs were €0.05 per tonne. However, for small firms, average transaction costs were €2.02—over 18% of the current allowance price. This supports the concerns that transaction costs are excessive for smaller participants. The immediate policy implication is that additional attention will be needed to address different sizes of firms, number of installations per firm, and the size of the initial allocations.  相似文献   
40.
“九·五“期间 ,厦门地震台实施 95 - 0 1 - 0 2项目 ,安装DSQ水管倾斜仪、SS -Y伸缩仪、VS型垂直摆和DZW重力仪等四台套数字形变仪器。众所周知 ,台址与环境改造、仪器设备和良好的管理是获得优秀的观测成果不可缺少的三个重要因素。而良好的台址条件与环境改造又是三要素之首。在台址确定之后 ,环境改造必须科学地、精心地组织设计与施工 ,以使工程质量达到最佳效果。本文阐述的即是该项目设计、施工的做法与经验  相似文献   
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