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621.
Because of large economic and environmental asymmetries among world regions and the incentive to free ride, an international climate regime with broad participation is hard to reach. Most of the proposed regimes are based on an allocation of emissions rights that is perceived as fair. Yet, there are also arguments to focus more on the actual welfare implications of different regimes and to focus on a ‘fair’ distribution of resulting costs. In this article, the computable general equilibrium model DART is used to analyse the driving forces of welfare implications in different scenarios in line with the 2?°C target. These include two regimes that are often presumed to be ‘fair’, namely a harmonized international carbon tax and a cap and trade system based on the convergence of per capita emissions rights, and also an ‘equal loss’ scenario where welfare losses relative to a business-as-usual scenario are equal for all major world regions. The main finding is that indirect energy market effects are a major driver of welfare effects and that the ‘equal loss’ scenario would thus require large transfer payments to energy exporters to compensate for welfare losses from lower world energy demand and prices.Policy relevanceA successful future climate regime requires ‘fair’ burden sharing. Many proposed regimes start from ethical considerations to derive an allocation of emissions reduction requirements or emissions allowances within an international emissions trading scheme. Yet, countries also consider the expected economic costs of a regime that are also driven by other factors besides allowance allocation. Indeed, in simplified lab experiments, successful groups are characterized by sharing costs proportional to wealth. This article shows that the major drivers of welfare effects are reduced demand for fossil energy and reduced fossil fuel prices, which implies that (1) what is often presumed to be a fair allocation of emissions allowances within an international emissions trading scheme leads to a very uneven distribution of economic costs and (2) aiming for equal relative losses for all regions requires large compensation to fossil fuel exporters, as argued, for example, by the Organization of Petroleum Exporting Countries (OPEC). 相似文献
622.
Florian Scholz Christian Hensen Rolf L. Romer Anette Meixner Matthias Haeckel 《Geochimica et cosmochimica acta》2009,73(18):5444-206
The chemical and isotopic composition of pore fluids is presented for five deep-rooted mud volcanoes aligned on a transect across the Gulf of Cadiz continental margin at water depths between 350 and 3860 m. Generally decreasing interstitial Li concentrations and 87Sr/86Sr ratios with increasing distance from shore are attributed to systematically changing fluid sources across the continental margin. Although highest Li concentrations at the near-shore mud volcanoes coincide with high salinities derived from dissolution of halite and late-stage evaporites, clayey, terrigenous sediments are identified as the ultimate Li source to all pore fluids investigated. Light δ7Li values, partly close to those of hydrothermal vent fluids (δ7Li: +11.9‰), indicate that Li has been mobilized during high-temperature fluid/sediment or fluid/rock interactions in the deep sub-surface. Intense leaching of terrigenous clay has led to radiogenic 87Sr/86Sr ratios (∼0.7106) in pore fluids of the near-shore mud volcanoes. In contrast, non-radiogenic 87Sr/86Sr ratios (∼0.7075) at the distal locations are attributed to admixing of a basement-derived fluid component, carrying an isotopic signature from interaction with the basaltic crust. This inference is substantiated by temperature constraints from Li isotope equilibrium calculations suggesting exchange processes at particularly high temperatures (>200 °C) for the least radiogenic pore fluids of the most distal location.Advective pore fluids in the off-shore reaches of the Gulf of Cadiz are influenced by successive exchange processes with both oceanic crust and terrigenous, fine-grained sediments, resulting in a chemical and isotopic signature similar to that of fluids in near-shore ridge flank hydrothermal systems. This suggests that deep-rooted mud volcanoes in the Gulf of Cadiz represent a fluid pathway intermediate between mid-ocean ridge hydrothermal vent and shallow, marginal cold seep. Due to the thicker sediment coverage and slower fluid advection rates, the overall geochemical signature is shifted towards the sediment-diagenetic signal compared to ridge flank hydrothermal environments. 相似文献
623.
Peter Herzsprung Elke Bozau Olaf Büttner Anja Duffek Kurt Friese Matthias Koschorreck Martin Schultze Wolf v. Tümpling Katrin Wendt‐Potthoff 《洁净——土壤、空气、水》2006,34(6):593-607
Pore water of sediments plays an important role in aquatic systems as mediator and as the reactive zone between the sediment and surface water. Sediment pore waters with high ionic strength from acidified pit lakes were investigated to obtain information about the influence on the lake water quality. The analysis of soluble reactive phosphorus, nitrate, ammonium, silica, dissolved organic carbon, ferrous iron, sulfate, chloride, sodium, potassium, calcium, magnesium, manganese, and total dissolved iron was predetermined as the dataset required for evaluation of water quality. The data collection procedure was optimised by designing a methodology for stabilisation, dilution of pore water samples and adaptation of analytical methods. The developed methodology was evaluated with respect to the effort required in the laboratory under routine conditions. In the first round of analyses, 72% of 638 individual analyses from a random selection of pore water profiles were found to be within the calibration ranges. Remedial actions to handle the remaining 28% of invalid analytical results are exemplified. Differences between comparative analyses of some ions by continuous flow analysis, ion chromatography, and atomic emission spectroscopy were evaluated. The majority of results measured by ion chromatography differed on a highly significant level from results measured by atomic emission spectroscopy. Possible reasons, originating from the extreme sample matrix, are discussed. Finally, the designed methodology and the results of the method comparison are used to recommend the selection of analytical methods under specific conditions. 相似文献
624.
Zamyatin Dmitry A. Shchapova Yuliya V. Votyakov Sergey L. Nasdala Lutz Lenz Christoph 《Mineralogy and Petrology》2017,111(4):475-497
Mineralogy and Petrology - The U-Th-Pb isotope system in the accessory mineral zircon may be disturbed, as for instance by the secondary loss of radiogenic lead. The recognition of such alteration... 相似文献
625.
Cratons are generally assumed to be regions of long-lasting tectonic stability. In particular the study of the Phanerozoic exhumation history of cratons has been largely hampered by the scarcity of suitable stratigraphic controls onshore. This fact is even more pronounced in terranes lacking Mesozoic or younger penetrative structural fabrics and metamorphic overprinting. Our study in the Limpopo belt shows that modern apatite fission track thermochronology provides a hitherto unavailable perspective in the study of these rocks, and has profound implications for the crustal evolution of the Zimbabwe Craton.Apatite fission track data from 35 samples taken along two transects, in the southern edge of the Zimbabwe Craton and in the Central Zone of the Limpopo Belt, suggest that extensive regions experienced kilometer-scale exhumation in two discrete events, as recently as the Cretaceous. The first occurred at around 130 Ma, and the second at around 90 Ma. Basin subsidence and sedimentation loads on the Mozambique margin support the timing of these events and provide strong indications of the source and pathways for the eroded material. Further, the results indicate that young and old “surfaces” (in a geomorphological sense) may be structurally juxtaposed in regions of high elevation in Zimbabwe. This is contrary to early ideas of surface chronologies based on summit accordances or invoking pediplanation. 相似文献
626.
627.
Matthias Kuhle 《第四纪研究》1992,12(2):166-166
十次考察任务期间,我们获得了西藏及其周围山地冰川最大规模的新资料。在喜马拉雅山和喀喇昆仑山南侧低至890m和980m的海拔高度上发现冰碛物。在青藏高原北坡的祁连山,冰碛物发现于2300m的海拔高度。在喀喇昆仑山、Aghil和昆仑山北坡,冰碛物也低达1900m。对冰漂砾的放射性分析表明,青藏高原南部和中部古冰体厚度至 相似文献
628.
Natural Hazards - Building a culture of risk is an essential objective within the integrated risk management paradigm. Challenges arise both due to increasing damage from natural hazards and the... 相似文献
629.
Matthias Mauder Raymond L. Desjardins Ian MacPherson 《Boundary-Layer Meteorology》2008,129(3):431-450
The objective of this study is to produce two-dimensional maps of the sensible and the latent heat fluxes from airborne measurements,
based on the analysis of a flight pattern, called grid flights. A footprint model with along-wind and cross-wind components
was used to project the measured fluxes onto the surface map. The method was applied to measurements over Arctic tundra during
the Mackenzie Area GEWEX (Global Energy and Water Cycle Experiment) Study (MAGS) 1999. The resulting flux estimates were computed
by integration of a wavelet transform, and corrected for long wavelength losses using information from 100 km long regional
runs that were conducted close to the grid flights. The random flux error was estimated based on the flight length that is
represented in each map element, and a map resolution of 3 × 3 km was chosen in order to keep the average random error of
the latent heat flux below 25%. The random error of the sensible heat flux was smaller by a factor of 1.4 on average. An analysis
of airborne flux measurements at different altitudes showed no significant increase of flux estimates for measurement heights
below 90 m. Thus, the fluxes measured at heights between 48 and 64 m were not corrected for vertical flux divergence. The
resulting flux maps provide quantitative two-dimensional estimates of the energy exchange between the surface and the atmosphere
during the snow melt period in an Arctic environment, which are well-suited for calibration and validation of numerical models. 相似文献
630.
Ten Years of Development of Equipment for Measurement of Atmospheric Radioactive Xenon for the Verification of the CTBT 总被引:1,自引:0,他引:1
Matthias Auer Timo Kumberg Hartmut Sartorius Bernd Wernsperger Clemens Schlosser 《Pure and Applied Geophysics》2010,167(4-5):471-486
Atmospheric measurement of radioactive xenon isotopes (radioxenon) plays a key role in remote monitoring of nuclear explosions, since it has a high capability to capture radioactive debris for a wide range of explosion scenarios. It is therefore a powerful tool in providing evidence for nuclear testing, and is one of the key components of the verification regime of the Comprehensive Nuclear-Test-Ban Treaty (CTBT). The reliability of this method is largely based on a well-developed measurement technology. In the 1990s, with the prospect of the build-up of a monitoring network for the CTBT, new development of radioxenon equipment started. This article summarizes the physical and technical principles upon which the radioxenon technology is based and the advances the technology has undergone during the last 10 years. In contrast to previously used equipment, which was manually operated, the new generation of radioxenon monitoring equipment is designed for automated and continuous operation in remote field locations. Also the analytical capabilities of the equipment were strongly enhanced. Minimum detectable concentrations of the recently developed systems are well below 1 mBq/m3 for the key nuclide 133Xe for sampling periods between 8 and 24 h. All the systems described here are also able to separately measure with low detection limits the radioxenon isotopes 131mXe, 133mXe and 135Xe, which are also relevant for the detection of nuclear tests. The equipment has been extensively tested during recent years by operation in a laboratory environment and in field locations, by performing comparison measurements with laboratory type equipment and by parallel operation. These tests demonstrate that the equipment has reached a sufficiently high technical standard for deployment in the global CTBT verification regime. 相似文献