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31.
ABSTRACTThe continuous submission and scaling-up of Nationally Determined Contributions (NDCs) constitutes a key feature of the Paris Agreement. In their NDCs, states propose governance mechanisms for implementation of climate action, in turn distinguishing appropriate roles for the state in climate governance. Clarity on Parties’ suggested roles for the state makes explicit assumptions on the premise of climate policy, in turn contributing to enhanced transparency in negotiations on the scaling-up of NDCs. This also speaks to ongoing debates on roles for the state in climate governance literature. This article identifies the governance mechanisms proposed by states in their NDCs and the roles for the state envisioned by those governance mechanisms, and also examines how cross-national patterns of roles for the state break or converge with conventional patterns of international politics. The analysis shows that states propose a plurality of roles, which to different extents may be complementary or conflictual. We conclude that income, region, and the Annexes under the United Nations Framework Convention on Climate Change (UNFCCC) are important for understanding suggested roles for the state, but that there are nuances to be further explored. We argue that this paper has three key findings: i) a majority of states rely on market mechanisms to implement their NDCs while rules on implementation and assessment of market mechanisms are still an outstanding issue in the negotiations, meaning that resolving this issue will be essential; ii) the process for evaluating and assessing qualitative governance mechanisms needs to be specified; and iii) increased awareness of differing views on the state’s roles makes explicit different perspectives on what constitutes an ambitious and legitimate contribution to combating climate change.Key policy insights
A majority of states (> 75%) envision the state as regulator (creating and strengthening legislation), market facilitator (creating and maintaining market structures), or facilitator (creating more favourable material conditions for climate-friendly behaviour).
Greater awareness of differing views on roles for the state can increase understanding of different perspectives on ambition and legitimacy of contributions, in turn facilitating trust in negotiations.
A distinction between substantive and procedural qualitative governance mechanisms and their function and interaction would facilitate the stocktaking dialogues.
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33.
北京耕地流失的时空动态与调控途径研究 总被引:10,自引:1,他引:10
在国际学术前沿土地变化科学的概念框架下, 耕地非农化及其调控机制研究成为核心问 题之一。研究中国快速城市化地区耕地非农化的驱动力及其调控机制, 不仅是现实的迫切需求, 也可在国际相关学术领域做出独特贡献。以北京为案例进行研究发现: 1996~2004 年北京土地利 用变化中, 大多数地类转换都与耕地直接有关, 耕地流失是北京土地利用变化的核心问题; 城镇 扩展主要占用耕地, 且耕地生产力高的平原地区因建设占用而流失的耕地量大; 远郊山区耕地被 建设占用的压力相对较小, 但被生态用地占用的压力相对较大; 人口增长、经济发展、政府行为与 决策是北京等经济快速发展地区耕地流失的重要驱动因素, 解决途径关键在于寻求耕地保护与 耕地非农利用之间的平衡点、积极发挥土地管理政策的调控作用。 相似文献
34.
Re-evaluation of focal depths and source mechanisms of selected earthquakes in the Afar depression 总被引:1,自引:0,他引:1
We present a stepwise inversion procedure to assess the focal depth and model earthquake source complexity of seven moderate-sized earthquakes (6.2 > M w > 5.1) that occurred in the Afar depression and the surrounding region. The Afar depression is a region of highly extended and intruded lithosphere, and zones of incipient seafloor spreading. A time-domain inversion of full moment tensor was performed to model direct P and SH waves of teleseismic data. Waveform inversion of the selected events estimated focal depths in the range of 17–22 km, deeper than previously published results. This suggests that the brittle–ductile transition zone beneath parts of the Afar depression extends more than 22 km. The effect of near-source velocity structure on the moment tensor elements was also investigated and was found to respond little to the models considered. Synthetic tests indicate that the size of the estimated, non-physical, non-isotropic source component is rather sensitive to incorrect depth estimation. The dominant double couple part of the moment tensor solutions for most of the events indicates that their occurrence is mainly due to shearing. Parameters associated with source directivity (rupture velocity and azimuth) were also investigated. Re-evaluation of the analysed events shows predominantly normal faulting consistent with the relative plate motions in the region. 相似文献
35.
Dominique Moran 《GeoJournal》2001,55(2-4):541-547
This paper explores the relationship between the forestry enterprises (leskhozi) and the inhabitants of forestry villages
in the northern rayony of Perm oblast, Russian Federation in the context of the `new regional geography'. These relationships
are compared with those identified between peasant farmers and collective and state farms post-1991, and a theory of the cultivation
of these relationships as a coping mechanism for both households and enterprises facing difficult economic circumstances is
advanced. The situation in the northern rayony is contextualised through discussion of the settlement and development history
of the region, which was a recipient of forced and voluntary labour migration during the Soviet period. The paper concludes
that in accordance with recent theories of post-communist regional development, the experience of transition in the northern
rayony of Perm oblast is determined at least in part by its social and economic context.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
36.
基于野外地质调查和构造测量工作,系统解析了萨热克巴依盆地边缘及内部的断裂-褶皱构造的几何学、运动学和动力学特征,重建盆地演化过程,探究控矿规律,促进深部找矿预测。研究表明:①盆地经历了早—中侏罗世拉分盆地发育、中侏罗世末—晚侏罗世初构造隆升剥蚀、晚侏罗世沉降、晚侏罗世末—早白垩世初构造隆升剥蚀、早白垩世早期沉降、早白垩世中晚期—古近纪隆升剥蚀、中新世压剪性构造变形、上新世—第四纪挤压收缩变形8个构造演化阶段,其中前6个阶段表现为沉降-抬升垂直运动,后2个阶段(新近纪—第四纪)表现为挤压收缩水平运动。②盆地叠加有2期挤压收缩构造变形,早期形成规模不大的北(西)西—南(东)东向宽缓向背斜构造;后期形成一系列北东东—南西西向褶皱-断层构造,表现为盆地边缘南北边界断层(ST、NT)朝盆地内对冲,导致在断层附近下盘形成的伴生褶皱趋于紧闭,而在远离断层的复式向斜(Sf)核部的次级褶皱多呈开阔宽缓状。③盆地构造控矿可以分为2个阶段:在成矿期阶段(早侏罗世—早白垩世),由盆地沉降、隆升形成的正断层、反转断层及伴生断裂-节理-裂隙为重要的导矿构造,上侏罗统库孜贡苏组砂砾岩层内发育的顺层裂隙为萨热克铜矿重要的储矿构造,导矿构造与储矿构造交汇部位成为矿液富集成矿的最佳部位;在成矿后阶段,由后期(上新世—第四纪)北北西—南南东向区域挤压应力作用形成的收缩构造变形,明显控制了矿体的空间展布形态,造成矿体卷入褶皱变形,以及被断裂-裂隙带切穿或错断。④在30勘探线以东一带,南矿带深部隐伏的库孜贡苏组上段(J3k2)为铜(锌)矿(化)体的有利赋存层位,具有良好的找矿前景。 相似文献
37.
38.
Shin'ichiro Ando Daisuke Nagai 《Monthly notices of the Royal Astronomical Society》2008,385(4):2243-2253
Cosmic rays produced in cluster accretion and merger shocks provide pressure to the intracluster medium (ICM) and affect the mass estimates of galaxy clusters. Although direct evidence for cosmic ray ions in the ICM is still lacking, they produce γ-ray emission through the decay of neutral pions produced in their collisions with ICM nucleons. We investigate the capability of the Gamma-ray Large Area Space Telescope ( GLAST ) and imaging atmospheric Čerenkov telescopes (IACTs) for constraining the cosmic ray pressure contribution to the ICM. We show that GLAST can be used to place stringent upper limits, a few per cent for individual nearby rich clusters, on the ratio of pressures of the cosmic rays and thermal gas. We further show that it is possible to place tight (≲10 per cent) constraints for distant ( z ≲ 0.25) clusters in the case of hard spectrum, by stacking signals from samples of known clusters. The GLAST limits could be made more precise with the constraint on the cosmic ray spectrum potentially provided by IACTs. Future γ-ray observations of clusters can constrain the evolution of cosmic ray energy density, which would have important implications for cosmological tests with upcoming X-ray and Sunyaev–Zel'dovich effect cluster surveys. 相似文献
39.
本文分析了临汾盆地现代地震在时序分布上的阶段性,平面分布上的丛集性,及其震源三维分布与分布地深部构造的关系,指出盆地北部的临汾-洪洞凹陷为该区未来若干年内的主要发震区,而20-30km深度则是主要发震层次。 相似文献
40.
Complex time-space spreading and focal mechanism of the 1989 Batang earthquake swarm (M_s=6.7) 总被引:1,自引:0,他引:1
Complex time-space spreading and focal mechanism of the 1989 Batang earthquake swarm (M_s=6.7)(程万正)(陈天长)Complextime-spacespre... 相似文献