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排序方式: 共有812条查询结果,搜索用时 15 毫秒
91.
利用GIS技术和RS技术减灾防灾   总被引:2,自引:1,他引:1  
减灾防灾是一项需要多学科知识融会贯通的长期工程。灾难的发生是由多种因素造成的,在分析管理的时候,需要大量的数据源,因而,分析过程相当地耗时耗费。近年,由于能够高效提供详细、精确的相关数据.GIS技术和RS技术在灾难管理方面应用广泛、发展迅速,遥感技术提供灾情数据.GIS技术通过模型将各种数据有机地整合起来,包括空间数据、非空间数据、属性数据,使它们在灾难管理的各个阶段发挥不同的作用。  相似文献   
92.
以2018年台湾海峡MS6.2地震造成的社会影响作为主要调查内容,选取了福建省东山县普通群众作为调查对象,从震时人的感觉、灾时应急避险情况、社会心理、防震减灾及地震预警知识普及情况等方面进行调查研究,目的是了解东山县居民地震应急避险情况及防震减灾知识普及程度等,为今后有针对性的做好防震减灾宣传,提升社会公众抵御地震灾害能力提供一定的参考。   相似文献   
93.
邹佑学  王睿  张建民 《岩土力学》2019,40(6):2443-2455
采用砂土液化大变形弹塑性本构模型分析可液化砂土,采用模量随应力与应变变化的等效非线性模型增量形式分析碎石桩,应用FLAC3D有限差分软件对地震动力作用下可液化场地碎石桩复合地基进行三维动力响应分析。模拟分析了在地震作用下碎石桩刚度效应和排水效应对加固处理可液化场地的抗液化效果,从初始小变形到液化后大变形的变形发展,超静孔压累积与消散,及桩与土的变形与应力分配变化等。结果表明,所用模型与方法可合理描述可液化场地碎石桩复合地基在地震作用下场地的动力响应特性和抗液化效果;在地震作用下可液化场地中桩周土体与碎石桩体的竖向应力与水平向剪切应力向碎石桩体集中,竖向有效应力比可降至约1/6~1/3;桩周土体与桩体为非协调变形,剪应变比可达7~10;碎石桩抗液化影响范围约为2.5~3倍桩径,对超过3.5倍桩径范围影响较小;碎石桩与砂土渗透系数比大于100时对降低砂土中超静孔隙水压影响明显;碎石桩对场地的加密效应可显著降低超静孔隙水压力,而碎石桩刚度则对超静孔隙水压力变动影响较小,但有助于减低地面加速度响应峰值。  相似文献   
94.
气候变化与多维度可持续城市化   总被引:1,自引:0,他引:1  
陈明星  先乐  王朋岭  丁子津 《地理学报》2021,76(8):1895-1909
全球大规模城市化和气候变化已是不争的事实,这是全人类需要共同面对和关注的突出问题。当前对于两者之间的复杂关系以及城市化进程如何科学应对气候变化并不清晰,从科学、管理到实践都需要进一步加强探究,以实现全球和区域可持续发展。本文首先给出全球大规模城市化和气候变化发生的基本事实,综述归纳城市化与气候变化的相互影响以及可能机制,城市化导致热岛效应、降水分配不均以及极端天气,并具有局地—区域—全球多尺度叠加效应,加剧了全球气候变化问题;气候变化对城市化的影响主要表现为能源消费变化、死亡率与传染病传播、海平面上升、极端天气对基础设施的破坏、水资源短缺等方面。简要梳理相关的国际研究和行动联盟,从城市化的4个关键维度:人口、土地、经济和社会视角出发,提出适应与减缓气候变化的多维度可持续城市化的分析框架。呼吁加强自然与人文学科交叉,将城市化等人类活动纳入地—气系统,探究人—地—气复杂耦合过程,从城市化为代表的人类活动角度的适应与减缓,或许是应对气候变化的最关键和最现实的路径。  相似文献   
95.
Sindhu K. 《国际地球制图》2017,32(9):1004-1016
Stream flow forecast and its inundation simulations prior to the event are an effective and non-structural method of flood damage mitigation. In this paper, a continuous simulation hydrological and hydrodynamic model was developed for stream flow forecast and for spatial inundation simulation in Brahmani–Baitarani river basin, India. The hydrologic modelling approach includes rainfall-run-off modelling, flow routing, calibration and validation of the model with the field discharge data. CARTOSAT Digital Elevation Model of 30 m resolution, land use/land cover derived from the Indian Remote Sensing Satellite (IRS-P6) AWiFS and soil textural data of the study area were used in the modelling to compute topographic and hydraulic parameters. The hydrological model was calibrated with the help of field observed discharge data of 2006 and 2009 and validated with the data of 2008 and 2011. From the results, it is found that computed discharges are very well matching well with the observed discharges. The developed model can provide the stream flow forecast with more than 30 h lead time. Possible flood inundations were simulated using hydrodynamic modelling approach. CARTO Digital Elevation Model of 10 m resolution, landuse and the computed flood hydrographs were used in inundation simulations.  相似文献   
96.
The use of shale gas is commonly considered as a low-cost option for meeting ambitious climate policy targets. This article explores global and country-specific effects of increasing global shale gas exploitation on the energy markets, on greenhouse gas emissions, and on mitigation costs. The global techno-economic partial equilibrium model POLES (Prospective Outlook on Long-term Energy Systems) is employed to compare policies which limit global warming to 2°C and baseline scenarios when the availability of shale gas is either high or low. According to the simulation results, a high availability of shale gas has rather small effects on the costs of meeting climate targets in the medium and long term. In the long term, a higher availability of shale gas increases baseline emissions of greenhouse gases for most countries and for the world, and leads to higher compliance costs for most, but not all, countries. Allowing for global trading of emission certificates does not alter these general results. In sum, these findings cast doubt on shale gas’s potential as a low-cost option for meeting ambitious global climate targets.

POLICY RELEVANCE

Many countries with a large shale gas resource base consider the expansion of local shale gas extraction as an option to reduce their GHG emissions. The findings in this article imply that a higher availability of shale gas in these countries might actually increase emissions and mitigation costs for these countries and also for the world. An increase in shale gas extraction may spur a switch from coal to gas electricity generation, thus lowering emissions. At the global level and for many countries, though, this effect is more than offset by a crowding out of renewable and nuclear energy carriers, and by lower energy prices, leading to higher emissions and higher mitigation costs in turn. These findings would warrant a re-evaluation of the climate strategy in most countries relying on the exploitation of shale gas to meet their climate targets.  相似文献   

97.
This paper offers a systematic analysis of the concepts and contexts that frame the climate-smart agriculture (CSA) discourse in the academic and policy literature. Documents (n?=?113) related to CSA and published in peer-reviewed journals, books, working papers, and scientific reports from 2004 to 2016 were reviewed. Three key trends emerged from the analysis: studies are biased towards global policy agendas; research focuses on scientific and technical issues; and the integration of mitigation, adaptation, and food security (the three pillars of CSA) is becoming a popular scholarly solution. Findings suggest that CSA is a fairly new concept used to describe a range of adaptation and mitigation practices without a specific set of criteria. Although CSA is often framed around the three pillars, the underlying issues constructing the discourse differ at global, developing, and developed country scales. Although there is increasing research on developing countries, particularly in relation to how CSA can transform smallholder agriculture, there is a paucity of research documenting the experiences from developed countries. The findings suggest that research on CSA needs to move beyond solely focussing on scientific approaches and only in certain geographical contexts. If CSA is to be applicable for farmers across the globe, then cross-disciplinary research that is underpinned by broad socio-economic and political contexts is essential to understand how differences in narratives might affect implementation on-the-ground in both developing and developed countries.

POLICY RELEVANCE

Although policy makers are increasingly supportive of the climate-smart agriculture (CSA) approach, the rhetoric has largely been developed on the basis of scientific and technical arguments. The political implications of varying perspectives have resulted in a growing divide between how developing and developed countries frame solutions to the impacts of climate change on agriculture under the 2015 Paris Agreement. Different framings are part of the explanation for why the scope of CSA is being rethought, with the scientific community redirecting attention to seeking a separate work programme under the United Nations Framework Convention on Climate Change (UNFCCC). The current policy framing of CSA will give no new policy direction unless it grounds itself in the smallholder farmer and civil society contexts.  相似文献   
98.
Although agriculture could contribute substantially to European emission reductions, its mitigation potential lies untapped and dormant. Market-based instruments could be pivotal in incentivizing cost-effective abatement. However, sector specificities in transaction costs, leakage risks and distributional impacts impede its implementation. The significance of such barriers critically hinges on the dimensions of policy design. This article synthesizes the work on emissions pricing in agriculture together with the literature on the design of market-based instruments. To structure the discussion, an options space is suggested to map policy options, focusing on three key dimensions of policy design. More specifically, it examines the role of policy coverage, instruments and transfers to farmers in overcoming the barriers. First, the results show that a significant proportion of agricultural emissions and mitigation potential could be covered by a policy targeting large farms and few emission sources, thereby reducing transaction costs. Second, whether an instrument is voluntary or mandatory influences distributional outcomes and leakage. Voluntary instruments can mitigate distributional concerns and leakage risks but can lead to subsidy lock-in and carbon price distortion. Third, the impact on transfers resulting from the interaction of the Common Agricultural Policy (CAP) with emissions pricing will play a key role in shaping political feasibility and has so far been underappreciated.

POLICY RELEVANCE

Following the 2015 Paris Agreement, European climate policy is at a crossroads. Achieving cost-effectively the 2030 and 2050 European targets requires all sectors to reduce their emissions. Yet, the cornerstone of European climate policy, the European Union Emissions Trading System (EU ETS), covers only about half of European emissions. Major sectors have been so far largely exempted from carbon pricing, in particular transport and agriculture. While transport has been increasingly under the spotlight as a possible candidate for an EU ETS sectoral expansion, policy discussions on pricing agricultural emissions have been virtually absent. This article attempts to fill this gap by investigating options for market-based instruments to reduce agricultural emissions while taking barriers to implementation into account.  相似文献   

99.
The shale gas boom in the United States spurred a shift in electricity generation from coal to natural gas. Natural gas combined cycle units emit half of the CO2 to produce the same energy as a coal unit; therefore, the market trend is credited for a reduction in GHG emissions from the US power sector. However, methane that escapes the natural gas supply chain may undercut these relative climate benefits. In 2016, Canada, the United States and Mexico pledged to reduce methane emissions from the oil and natural gas sector 40–45% from 2012 levels by 2025. This article reviews the science-policy landscape of methane measurement and mitigation relevant for meeting this pledge, including changes in US policy following the 2016 presidential election. Considerable policy incoherence exists in all three countries. Reliable inventories remain elusive; despite government and private sector research efforts, the magnitude of methane emissions remains in dispute. Meanwhile, mitigation efforts vary significantly. A framework that integrates science and policy would enable actors to more effectively inform, leverage and pursue advances in methane measurement and mitigation. The framework is applied to North America, but could apply to other geographic contexts.

Key policy insights

  • The oil and gas sector’s contribution to atmospheric methane concentrations is becoming an increasingly prominent issue in climate policy.

  • Efforts to measure and control fugitive methane emissions do not presently proceed within a coherent framework that integrates science and policy.

  • In 2016, the governments of Canada, Mexico and the United States pledged to reduce methane emissions from the oil and natural gas sector 40–45% from 2012 levels by 2025.

  • The 2016 presidential election in the United States has halted American progress at the federal level, suggesting a heavier reliance on industry and subnational efforts in that country.

  • Collectively or individually, the countries, individual agencies, or private stakeholders could use the proposed North American Methane Reduction framework to direct research, enhance monitoring and evaluate mitigation efforts, and improve the chances that continental methane reduction targets will be achieved.

  相似文献   
100.
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