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91.
Abstract

Given a certain pre-existing commitment to sea-level rise due to the long thermal lags of the ocean system, several million people living in coastal areas and small islands will inevitably be displaced by the middle of the century. These climate exiles will have nowhere to go. Rather than deal with this in an ad hoc manner as the problem arises, the authors propose a mechanism by which these exiles would be given immigration benefits by countries through a formula that ties numbers of immigrants to a country's historical greenhouse gas emissions. Such a compensatory mechanism appears to be a fair way of addressing the problems faced by climate exiles.  相似文献   
92.
How do current processes in international climate-related institutions affect the architecture of a future climate regime, particularly various international negotiating processes related to climate change? A plausible image of future climate regime is developed to address this question. Three plausible scenarios are described for the next decade using the scenario-planning approach. Based on this, the scope for an internationally acceptable climate regime beyond 2012 is developed. The current processes under the UNFCCC, the Kyoto Protocol, and those outside the UN arena are encapsulated into three scenarios. Each scenario has a set of relatively preferable types of commitments, which differ from each other. Each process is likely to result in the establishment of one particular institution. Linkages are developed between the three institutions so that the climate regime as a whole will be environmentally effective. The three institutions are likely to converge in the long run, as countries' views on both climate change and a future climate regime converge.  相似文献   
93.
海草床生态监测的作用不仅在于探讨海草资源本身的现状与发展趋势,更可通过海草监测,来评估所在海区的近海生态环境质量,或提示其它一些生态问题。在海草监测与保护方面,广西乃至中国仍远远落后于澳大利亚、美国以及欧洲一些国家和地区。对广西北部湾而言,仍缺乏具有较强针对性、可操作性和科学性的海草床生态监测方案。基于SeagrassNet监测方法,作者结合了近年来在广西开展的海草生态监测的经验,并针对广西北部湾海草生态系统的特殊性与典型性进行了部分改进,提出了适合于广西北部湾海草床的生态监测方案,是SeagrassNet在广西北部湾本土化的表现,具有较强的科学性和可操作性,以期为我国海草床的生态监测提供借鉴。  相似文献   
94.
This paper presents an alternative framework to the approach currently embodied in the Kyoto Protocol for managing global climate change post-2012. The framework has two key provisions. The first is that each person in the world would be ‘allowed’ an equal amount of greenhouse gas (GHG) emissions. This is labeled the equity-first provision. The second provision focuses on incorporating risk concepts into the setting of GHG emission reductions. It is proposed that the global climate be managed as to avoid three categories of risks: (I) Substantial regional economic, political, and/or biological impacts; (II) Severe global economic, political, and/or biological impacts; and (III) Extinction of humans. Acceptable risk thresholds are suggested to be one-in-a-million, one-in-one-hundred-million, and one-in-ten-billion, respectively. This equity-first, risk-based framework overcomes many criticisms of the current Kyoto Protocol: it explicitly involves all countries on earth; it avoids several administrative issues that are anticipated to plague a global carbon emissions trading market; and it avoids several contentious issues associated with pegging carbon emission reductions to 1990 levels. Because the framework is risk-based and emissions are tied to population and not historic emission levels, the basic framework would not have to be frequently renegotiated, as will be needed for the Kyoto-style approach to take the world past that agreement's 2012 endpoint.  相似文献   
95.
基于PC网络的多通道视景仿真技术   总被引:3,自引:0,他引:3  
王蒙  夏青 《测绘学院学报》2005,22(1):54-57,61
多通道视景仿真系统能够为用户带来强烈的沉浸感和大范围的视野。这类系统通常是以昂贵的专用图形工作站为硬件平台,难以为普通用户接受。文中研究了一种基于PC网络的多通道视景仿真系统,给出了该系统的软硬件结构及实现方法,并分析了系统运行的实验结果。  相似文献   
96.
In the past decade and a half, key international agreements have established systems of access and benefit sharing that aim to obtain consent and provide compensation for commercial use of plants, animals, and microorganisms—particularly those sourced in the Global South. Yet the rise of genomics, gene editing and synthetic biology may threaten the legitimacy of these agreements. Thus far, agreements have governed these resources in their physical form—as organisms in situ or germplasm in gene banks. However, both public and private research are increasingly utilizing genomic sequences and associated information. As a result of this shift, debates are unfolding at international fora such as the Convention on Biological Diversity and the International Treaty on Plant Genetic Resources for Food and Agriculture on whether existing agreements apply to physical resources only, or also to their sequence data or other associated information. Some call uninhibited access to digital sequence information (DSI) a new form of biopiracy, whereby digital resources are used without permission from those in the Global South. Others argue that access to DSI should remain unencumbered by bureaucracy, as it is key to biodiversity conservation and food security. This paper examines these debates over DSI and the rationales and justifications employed by the two sides, which loosely follow a divide between Global South and North. We find that different conceptualizations of genetic resources—particularly with regard to when, where and how value is added—define respective positions. Outcomes of these debates have important implications for management of global biodiversity, food security and issues of equity and justice for actors in biodiverse regions of the world.  相似文献   
97.
Pollution embodied in trade: The Norwegian case   总被引:9,自引:0,他引:9  
With the increase in international trade, it is becoming increasingly important to accurately determine environmental impacts resulting from pollution embodied in trade. Many previous studies have unrealistically assumed that imports are produced with the technology of the importing country. For countries with diverging technology and energy mixes the likely errors are significant. This study uses a model that explicitly includes regional technology differences to the case of Norway. It is found that CO2 emissions embodied in imports was 67% of Norway's domestic emissions. Around a half of this embodied pollution originates in developing countries, yet they represent only 10% of the value of Norwegian imports. In addition the carbon leakage from non-Annex I countries was at least 30%. We then argue that basing emission inventories on consumption, rather than production, may resolve not only issues related to international trade, but also provide greater flexibility towards pollution intensive resource endowments, emission reductions, and participation levels.  相似文献   
98.
A series of coesite,coexisting with or without a liquid phase,was synthesized in the nominal system SiO2-H2O at800-1450℃and 5 GPa.Micro-Raman spectroscopy was used to identity the crystalline phase,electron microprobe and LA-ICP-MS were employed to quantity some major and trace elements,and unpolarized FTIR spectroscopy was applied to probe the different types of hydrogen defects,explore water-incorporation mechanisms and quantify water contents.Trace amounts of A1 and B were detected in the coesite.Combining our results with the results in the literatures,we have found no positive correlation between the Al contents and the"Al"-based hydrogen concentrations,suggesting that previously proposed hydrogen-incorporation mechanism H^++Al^3+■Si^4+does not function in coesite.In contrast,we have confirmed the positive correlation between the B contents and the B-based hydrogen concentrations.The hydrogen-incorporation mechanism H^++B3^+■Si^4+readily takes place in coesite at different P-T conditions,and significantly increases the water content at both liquid-saturated and liquid-undersaturated conditions.For the SiO2-H2O system,we have found that type-Ⅰhydrogarnet substitution plays a dictating role in incorporating water into coesite at liquid-saturated condition,type-II hydrogarnet substitution contributes significantly at nearly dry condition,and both operate at conditions in between.The water solubility of coesite,as dictated by the type-Ⅰhydrogarnet substitution,positively correlates with both P and T,cH2O=-105(30)+5.2(32)×P+0.112(26)×T,with cH2O in wt ppm,P in GPa and T in℃.Due to its low water solubility and small fraction in subducted slabs,coesite may contribute insignificantly to the vertical water transport in subduction zones.Furthermore,the water solubility of any coesite in exhuming ultra-high pressure metamorphic rocks should be virtually zero as coesite becomes metastable.With an adequately fast waterdiffusion rate,this metastable coesite should be completely dry,which may have been the key factor to the partial preservation of most natural Coe.As a byproduct,a new IR experimental protocol for accurate water determination in optically anisotropic nominally anhydrous minerals has been found.Aided with the empirical method of Paterson(1982)it employs multiple unpolarized IR spectra,collected from randomly-orientated mineral grains,to approximate both total integrated absorbance and total integrated molar absorption coefficient.Its success relies on a high-level orientation randomness in the IR analyses.  相似文献   
99.
我国农田土壤碳库演变研究:全球变化和国家粮食安全   总被引:99,自引:0,他引:99  
《京都议定书》已于2005年生效,我国面临着CO2减排的巨大压力。分析了我国农业土壤有机碳库及其演变研究的现状,认为当前我国农业在耕地资源严重短缺、耕地地力趋于下降的背景下面临着2个巨大挑战:提高和稳定粮食生产能力与补偿日益增加的工业CO2排放。有机碳贫乏作为我国耕地土壤的基本特点,这一方面提供了我国较大的固碳空间,另一方面也体现了我国实施固碳农业的必要性和紧迫性。目前迫切需要了解我国农业土壤在最近20年来的碳库演变态势与规模,明确我国农业土壤的固碳潜力与容量,在国家层面上实施农业固碳稳产工程,以在农业可持续发展和争取国家CO2排放的较大配额上实现双嬴。   相似文献   
100.
Forest carbon sinks have been included in the Kyoto Protocol as one of the mechanisms for mitigating climate change. Consequently, credited sinks decrease the need to reduce emissions.We analyse in detail both the economywide and the sectoral effects of inclusion of carbon sinks as agreed upon in Bonn and Marrakesh for the first commitment period of 2008–2012. The focus of our analysis is the special treatment for Canada and Japan that allows them larger sinks. The analysis is performed with the multi-region computable general equilibrium (CGE) model GTAP-E.

New Zealand benefits most from the inclusion of sinks as it gains large carbon sinks from afforestation. Also in Sweden, Canada and Japan the costs of achieving the emission target are considerably reduced. Of these countries, only Canada has high costs without sinks. Thus credited sinks partly reduce the difference in economic burden of achieving the Kyoto target among countries. Even though larger sinks clearly benefit Canada and Japan, their effect on other countries, either on the economywide or on the sectoral level, remains marginal. Allowing larger sinks is, indeed, of relatively minor importance for the world economy and emission reduction, compared to the US withdrawal from the Kyoto Protocol.  相似文献   
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