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111.
Nigel W. Arnell Jason A. Lowe Ben Lloyd-Hughes Timothy J. Osborn 《Climatic change》2018,147(1-2):61-76
The 2015 Paris Agreement commits countries to pursue efforts to limit the increase in global mean temperature to 1.5 °C above pre-industrial levels. We assess the consequences of achieving this target in 2100 for the impacts that are avoided, using several indicators of impact (exposure to drought, river flooding, heat waves and demands for heating and cooling energy). The proportion of impacts that are avoided is not simply equal to the proportional reduction in temperature. At the global scale, the median proportion of projected impacts avoided by the 1.5 °C target relative to a rise of 4 °C ranges between 62 and 95% across sectors: the greatest reduction is for heat wave impacts. The 1.5 °C target results in impacts that would be between 27 and 62% lower than with the 2 °C target. For each indicator, there are differences in the proportions of impacts avoided between regions depending on exposure and the regional changes in climate (particularly precipitation). Uncertainty in the proportion of impacts that are avoided for a specific sector depends on the range in the shape of the relationship between global temperature change and impact, and this varies between sectors. 相似文献
112.
Emission reductions improve the chances that dangerous anthropogenic climate change will be averted, but could also cause some firms financial distress. Corporate failures, especially if they are unnecessary, add to the social cost of abatement. Social value can be permanently destroyed by the dissolution of organizational capital, deadweight losses paid to liquidators, and unemployment. This article proposes using measures of corporate solvency as an objective tool for policy makers to calibrate the optimal stringency of climate change policies, so that they can deliver the least loss of corporate solvency for a given level of emission reductions. They could also be used to determine the generosity of any compensation to address losses to corporate solvency. We demonstrate this approach using a case study of the UK’s Carbon Price Support (a carbon tax).
Key policy insights
Solvency metrics could be used to empirically calibrate the optimal stringency of climate policies.
An idealized solvency trajectory for firms affected by climate change policy would cause corporate solvency to initially decline – approaching but not exceeding ‘distressed’ levels – and then gradually improve to a new ‘steady state’ once the low-carbon transition had been achieved.
In terms of the UK’s Carbon Price Support, corporate solvency of energy-intensive industries was found to be stable subsequent to its introduction. Therefore, the available evidence does not support its later weakening.
113.
中国城市群多中心网络的拓扑结构 总被引:6,自引:1,他引:5
在既有理论基础上扩展了城市群多中心网络的度量工具,考察中国12个城市群总部—分支机构的企业关联网络,比较梳理了地级城市空间联系的拓扑结构。实证研究发现:①包括长三角、珠三角和京津冀三大典型城市群在内,中国城市群内部网络系统的拓扑结构依然发育不完善,在联系数据方面均呈现出一定的稀疏矩阵特征,空间组合关系均为树状结构。②总部区位(出度)的层级性差异均高于分支机构区位(入度)的层级性差异,显示出城市群内部空间“流”的不对称性。③针对12个城市群内部网络的拓扑结构聚类分析表明:长三角、珠三角、京津冀、山东半岛、海峡西岸地区的城市群内部网络联系较为紧密,呈现出一定程度的一体化网络特征;其中三大典型城市群存在明显的企业总部集聚核心,其余城市群内部的网络联系松散,跨城企业联系比重较低,在拓扑结构上大多呈现出以省会或副省级城市为指向的向心式联系。 相似文献
114.
115.
Mark A. Rathmell Margaret M. Streepey Eric J. Essene Ben A. van der Pluijm 《Contributions to Mineralogy and Petrology》1999,134(2-3):217-231
The Elzevir Terrane of the Grenville Orogen in southern Ontario contains metapelites and abundant graphitic marbles that
were regionally metamorphosed from the upper greenschist to upper amphibolite facies. Comparative thermometry was undertaken
with widely used calibrations for the systems garnet-biotite, calcite-dolomite, and calcite-graphite. Temperatures that are
obtained from matrix biotites paired with prograde garnet near-rim analyses are usually consistent with those determined using
calcite-graphite thermometry. However, calcite-graphite thermometry occasionally yields low temperatures due to lack of equilibration
of anomalously light graphite. Application of calcite-graphite and garnet-biotite systems may yield temperatures up to 70 °C
higher than calcite-dolomite in amphibolite facies rocks. Calcite-dolomite temperatures most closely approach those from calcite-graphite
and garnet-biotite when the samples contain a single generation of dolomite and calcite grains contain no visible dolomite
exsolution lamellae. However, some of these samples yield temperatures considerably lower than temperatures calculated from
calcite-graphite and garnet-biotite thermometry, indicating that the calcite-dolomite thermometer may have been partially
reset during retrogression. Estimated peak metamorphic temperatures of regional metamorphism between Madoc (upper greenschist
facies) and Bancroft (upper amphibolite facies) range from 500 to 650 °C. These results place the chlorite-staurolite isograd
at 540 °C, the kyanite-sillimanite isograd at 590 °C, and the sillimanite-K-feldspar isograd at 650 °C. Although each thermometer
may have an absolute uncertainty of as much as ±50 °C, the 50 to 60 °C temperature differences between the isograds are probably
accurate to 10 to 20 °C. An incomplete picture of the thermal gradients can result from the application of only one thermometer
in a given area. Simultaneous application of several systems allows one to recognize and overcome the inherent limitations
of each thermometer.
Received: 26 March 1997 / Accepted: 15 April 1998 相似文献
116.
117.
Oussama Abidi Mohamed Hédi Inoubli Kawthar Sebei Adnen Amiri Haifa Boussiga Imen Hamdi Nasr Abdelhamid Ben Salem Mahmoud Elabed 《Surveys in Geophysics》2017,38(3):617-649
The Maastrichtian–Paleocene El Haria formation was studied and defined in Tunisia on the basis of outcrops and borehole data; few studies were interested in its three-dimensional extent. In this paper, the El Haria formation is reviewed in the context of a tectono-stratigraphic interval using an integrated seismic stratigraphic analysis based on borehole lithology logs, electrical well logging, well shots, vertical seismic profiles and post-stack surface data. Seismic analysis benefits from appropriate calibration with borehole data, conventional interpretation, velocity mapping, seismic attributes and post-stack model-based inversion. The applied methodology proved to be powerful for charactering the marly Maastrichtian–Paleocene interval of the El Haria formation. Migrated seismic sections together with borehole measurements are used to detail the three-dimensional changes in thickness, facies and depositional environment in the Cap Bon and Gulf of Hammamet regions during the Maastrichtian–Paleocene time. Furthermore, dating based on their microfossil content divulges local and multiple internal hiatuses within the El Haria formation which are related to the geodynamic evolution of the depositional floor since the Campanian stage. Interpreted seismic sections display concordance, unconformities, pinchouts, sedimentary gaps, incised valleys and syn-sedimentary normal faulting. Based on the seismic reflection geometry and terminations, seven sequences are delineated. These sequences are related to base-level changes as the combination of depositional floor paleo-topography, tectonic forces, subsidence and the developed accommodation space. These factors controlled the occurrence of the various parts of the Maastrichtian–Paleocene interval. Detailed examinations of these deposits together with the analysis of the structural deformation at different time periods allowed us to obtain a better understanding of the sediment architecture in depth and the delineation of the geodynamic evolution of the region. 相似文献
118.
Sergio Martos‐Rosillo Carolina Guardiola‐Albert Alberto Padilla Benítez Joaquín Delgado Pastor Antonio Azcón González Juan José Durán Valsero 《Ground water》2018,56(3):362-365
The correct characterization of aquifer parameters is essential for water‐supply and water‐quality investigations. Slug tests are widely used for these purposes. While free software is available to interpret slug tests, some codes are not user‐friendly, or do not include a wide range of methods to interpret the results, or do not include automatic, inverse solutions to the test data. The private sector has also generated several good programs to interpret slug test data, but they are not free of charge. The computer program SlugIn 1.0 is available online for free download, and is demonstrated to aid in the analysis of slug tests to estimate hydraulic parameters. The program provides an easy‐to‐use Graphical User Interface. SlugIn 1.0 incorporates automated parameter estimation and facilitates the visualization of several interpretations of the same test. It incorporates solutions for confined and unconfined aquifers, partially penetrating wells, skin effects, shape factor, anisotropy, high hydraulic conductivity formations and the Mace test for large‐diameter wells. It is available in English and Spanish and can be downloaded from the web site of the Geological Survey of Spain. Two field examples are presented to illustrate how the software operates. 相似文献
119.
ABSTRACT The Ganjiang River is the largest tributary of Poyang Lake in China, and its hydrological regime variation greatly affects the utilization of regional water resources and the ecological environment of the lake. In this study, a novel trend analysis method, the Moving Average over Shifting Horizon (MASH), was applied to investigate the inter- and intra-annual trends of flow and water level from 1976 to 2016 at the Xiajiang and the Waizhou hydrological stations in the Ganjiang River. The Significant Change Rate Method (SCRM) was proposed to determine the MASH averaging parameters. The trend analysis results show a statistically significant decrease in water level series throughout the year and the relationship of flow and water level have changed greatly at the Waizhou station. The sediment load reduction, large-scale sand mining and water level decrease of Poyang Lake are identified as the main causes for the water level decrease. 相似文献
120.
垫状植物是高寒地区广泛分布的一类具有特殊形态的植物,被称为高寒生态系统工程师,其在高寒退化草地中的作用如何?本研究以位于西藏当雄念青唐古拉山脉南坡4500m的一处高寒退化草地为例,调查了垫状点地梅覆盖区域内外的物种多样性、土壤养分以及水分的差异。结果表明:垫状点地梅可以显著改善土壤养分,提高幅度大约为16%-48%,其中有机质和总氮(N)分别增加了16.2%和18.9%;局部土壤含水量提高约12%;样方内的物种丰富度(S)、Shannon-Wiener指数(H)和Simpson指数(D)都随着垫状点地梅盖度的增加而呈增加的趋势。垫状点地梅在退化草地中具有显著的改善土壤微环境和提高群落物种多样性的作用,应加强保育以促进高寒退化草地的恢复。 相似文献