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91.
Constraining global average temperatures to 2 °C above pre-industrial levels will probably require global energy system emissions to be halved by 2050 and complete decarbonization by 2100. In the nationally orientated climate policy framework codified under the Paris Agreement, each nation must decide the scale and method of their emissions reduction contribution while remaining consistent with the global carbon budget. This policy process will require engagement amongst a wide range of stakeholders who have very different visions for the physical implementation of deep decarbonization. The Deep Decarbonization Pathways Project (DDPP) has developed a methodology, building on the energy, climate and economics literature, to structure these debates based on the following principles: country-scale analysis to capture specific physical, economic and political circumstances to maximize policy relevance, a long-term perspective to harmonize short-term decisions with the long-term objective and detailed sectoral analysis with transparent representation of emissions drivers through a common accounting framework or ‘dashboard’. These principles are operationalized in the creation of deep decarbonization pathways (DDPs), which involve technically detailed, sector-by-sector maps of each country’s decarbonization transition, backcasting feasible pathways from 2050 end points. This article shows how the sixteen DDPP country teams, covering 74% of global energy system emissions, used this method to collectively restrain emissions to a level consistent with the 2 °C target while maintaining development aspirations and reflecting national circumstances, mainly through efficiency, decarbonization of energy carriers (e.g. electricity, hydrogen, biofuels and synthetic gas) and switching to these carriers. The cross-cutting analysis of country scenarios reveals important enabling conditions for the transformation, pertaining to technology research and development, investment, trade and global and national policies.

Policy relevance

In the nation-focused global climate policy framework codified in the Paris Agreement, the purpose of the DDPP and DDPs is to provide a common method by which global and national governments, business, civil society and researchers in each country can communicate, compare and debate differing concrete visions for deep decarbonization in order to underpin the necessary societal and political consensus to design and implement short-term policy packages that are consistent with long-term global decarbonization.  相似文献   
92.
李雪  咸迪  亓永刚  徐喆  钱建梅 《气象科技》2016,44(4):692-696
简述了目前我国风云卫星数据服务以及气象服务效益评估业务的现状,利用层次分析法提出风云卫星数据服务评价的6个1级指标和19个2级指标。设计了风云卫星数据服务评测量表,并采用分半信度、因子分析等方法对量表作信度和效度分析,结果表明所设计的评测量表具有良好的信度和效度,确定了包括服务平台易用性、服务流程规范性、服务响应及时性、服务内容完整性、服务工作主动性、服务宣传广泛性等6个方面的风云卫星数据服务评价指标。  相似文献   
93.
鄂尔多斯盆地北部直罗组有机质特征及与铀成矿关系   总被引:2,自引:0,他引:2  
本文研究了鄂尔多斯盆地典型铀矿床的有机质与铀成矿的关系。探讨了煤屑的赋存状态、煤质特征及成熟度,认为煤屑的演化程度均较低,处于低成熟阶段,有利于对铀的吸附。总体上看煤质有机质和铀矿化关系密切,铀含量与煤屑含量呈正相关关系,对铀矿物为吸附态形式。通过对该区油气包裹体的研究认为,该区存在多期次的成岩方解石胶结过程,并伴随多期次的油气包裹体发育,尤以晚期的胶结方解石矿物中存在丰富的晚期油气包裹体。研究认为晚期可能发生过油、气的运移和聚集,铀矿床的形成与赋矿砂岩中有机流体或还原性气体的充注和络合作用密切相关,因而这些丰富的有机流体和还原性气体对于铀的富集沉淀具有重要意义。  相似文献   
94.
鹿荻  陈锴 《测绘科学》2016,41(3):28-33
为了提高地球重力场模型不适定方程求解的精度,该文采用谱分析方法从级数展开阶数、数据采样率及数据缺失量3个方面探索影响数学拟合效果的根本因素:从常用的三角级数及勒让德级数模型出发,引出重力场拟合模型球谐函数模型,观察在改变级数展开阶数、数据采样率及数据缺失量等情况下所对应设计矩阵谱结构的变化,并从微观上研究影响误差分配的有关因素及最小奇异值对误差的决定性作用,为探求重力场模型解不准的原因及实现更高精度的全球重力场模型的建立提供参考。  相似文献   
95.
罗安  蔡地  李一  王勇 《测绘科学》2016,41(12):179-183
针对传统基于Flash、Slivelight的移动终端热图绘制中存在的数据表现单一、绘制效率低、用户体验差等问题,以及HTML5的渲染效率差、数据复用率低等性能缺点,该文提出一种改进的HTML5专题热图实时绘制方法。引入四叉树结构进行专题数据组织,大幅度提升热图实时绘制中服务器端数据汇聚效率;采用网格化数据缓存调度方法,有效降低客户端与服务器端的数据请求,实现移动终端数据缓存最大限度的重复利用;以异步I/O消息机制,解决了热图绘制过程中的消息通道堵塞、客户端假死等问题。实验证明,该方法符合移动终端对专题热图的绘制要求,能够在提高数据利用率和系统整体性能的同时,降低移动终端的计算量,提高系统的运行效率。  相似文献   
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The present study gathers a large amount of both existing and unpublished biostratigraphic data, which allows a detailed and complete definition of the stratigraphic features of the late Oligocene–late Miocene Maltese Archipelago sedimentary succession, recording in turn the tectonic and eustatic history of the Central Mediterranean region. We selected five sections in the Malta Island and three in Gozo, representative of the entire sedimentary succession, affected by well-known erosional surfaces, correlated to low-stands of the sea level, often associated with phoshatic layers, linked to the subsequent high-stands. The sedimentary interval, and thus the associated hiatuses, was constrained both by the bio-chronostratigraphic attribution and by the comparison with the third-order succession of the New Jersey passive margin, which shows strict analogy with the geodynamic context in which the Maltese succession deposited. The diachroneity at the base of the formations in the different sections, and the presence of intraformational unconformity/hiatuses, highlighted the role of the tectonic, which depicted a complex sedimentary basin, characterized by more distal versus more marginal sectors. Furthermore, the possibility to compare the sedimentary succession with the oxygen isotope curve connects the sedimentation interruptions, recorded within the Maltese Archipelago deposits, to global cooling events.

  相似文献   
99.

The last few years have seen the debate on the geoethics of environmental and climatic protection growing to include resilience as a central idea within this new discipline, which holds many similarities with geography. Resilience analysis often looks at the capacity to re-establish conditions of equilibrium within a system which has been hit by a serious shock, e.g. a natural or man-made disaster. Geoethics works, in tandem with geological analyses and the geography of risk, to inform a population and develop integrated risk management in such a way as to strengthen a community’s resilience. The aim of this work is to study some people’s capacity to overcome what was potentially a disastrous event and, through a process of reconstruction, turn it into an occasion for growth. The experiment, carried out in the primary and middle schools in Aiello Calabro (Calabria, southern Italy), was conducted on the basis of the belief that there is a close relationship between a population’s having a realistic understanding of the risk of such an event, e.g. an earthquake, and high levels of resilience. We also tried to gain an insight into the relationship that may exist between resilience in primary and secondary school children and methods of coping which give an appropriate management of seismic risk. To be more precise, we try to discover whether there is a link between good/appropriate resilience and good/appropriate risk management.

  相似文献   
100.
It is generally accepted that the compositions and properties of soil organic matter (SOM) are influenced by many factors. In order to reveal the effects of soil texture on characteristics and dynamics of SOM and its sub-fraction, humic acid (HA), along two soil profiles, a yellow soil profile and a purplish soil profile, under the same climate and vegetation conditions were determined. Results indicate that the decomposition and humification degrees of SOM and HA of the purplish soils are higher than those of the corresponding yellow soils indicated by A/O–A ratios of HAs, TOCs and HA yields of bulk soil samples, nevertheless, the development degree of the purplish soil is lower than that of the yellow soil. The variations of E4/E6 ratios of HAs along the soil profiles indicate the overall molecular sizes of HAs decreased downward along the soil profiles. A/O–A ratios of HAs decreased downward along both the soil profiles indicate that humification processes decrease downward along both the soil profiles. Leaching of SOM shows significant effects on the distribution and characteristics of HAs in the yellow soil profile but the purplish soil profile, which is consistent with the higher hydrophobicity of HAs in purplish soils, shows that the distribution characteristics of SOM along the soil profiles are a complex result of the combination of soil texture and characteristics of SOM itself. The remarkably different sand contents are concluded tentatively as one of reasons to the different distributions and dynamics of HAs along the soil profiles, however, to profoundly understand the evolution and transport of SOM along soil profiles needs more researches.  相似文献   
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