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101.
This paper analyzes the regional distribution of climate change mitigation costs in a global cap-and-trade regime. Four stylized burden-sharing rules are considered, ranging from GDP-based permit allocations to schemes that foresee a long-term convergence of per-capita emission permits. The comparison of results from three structurally different hybrid, integrated energy-economy models allows us to derive robust insights as well as identify sources of uncertainty with respect to the regional distribution of the costs of climate change mitigation. We find that regional costs of climate change mitigation may deviate substantially from the global mean. For all models, the mitigation cost average of the four scenarios is higher for China than for the other macro-regions considered. Furthermore, China suffers above-world-average mitigation costs for most burden-sharing rules in the long-term. A decomposition of mitigation costs into (a) primary (domestic) abatement costs and (b) permit trade effects, reveals that the large uncertainty about the future development of carbon prices results in substantial uncertainties about the financial transfers associated with carbon trade for a given allocation scheme. This variation also implies large uncertainty about the regional distribution of climate policy costs.  相似文献   
102.
103.
The authors have investigated the biochemical events by which marine algal virus infection induces cell cycle arrest. The key G2/M-phase regulatory proteins are analyzed by immunobloting in unicellular Emiliania huxleyi, suggesting that virus induced cell cycle arrest is related with virus''s effect on cyclins and cyclin dependent kinases. E. huxleyi virus (EhV) represses Cdc2/cyclinB complex activity by inhibiting the activity of Cdc2 kinase in a phosphorylation-related manner, blocking host cells G2/M checkpoint. Dephosphorylated/inactive Cdc25C combined with up-regulation of Wee1 expression at early infect period appears to be important mechanisms by which EhV represses Cdc2/cyclinB complex activity that is required for entry into M phase. This study has allowed us to confirm that algal virus infection leads to selective activation or inhibition of certain cell-cycle factors, which may play a significant role in establishing a more efficient environment for viral gene expression and DNA replication.  相似文献   
104.
Several studies have analysed the atmospheric response to sea-ice changes in the Arctic region, but only few have considered the Antarctic. Here, the atmospheric response to sea-ice variability in the Southern Hemisphere is investigated with the atmospheric general circulation model ECHAM5. The model is forced by the present and a projected future seasonal cycle of Antarctic sea ice. In September, the mean atmospheric response exhibits distinct similarities to the structure of the negative phase of the Southern Annular Mode, the leading mode of Southern Hemisphere variability. In the reduced Antarctic sea-ice integration, there is an equatorward shift of the Southern Hemisphere mid-latitude jet and the storm tracks. In contrast to a recent previous study, our findings indicate that a substantial impact of Southern Hemispheric future sea-ice reduction on the mid-latitude circulation cannot be ruled out.  相似文献   
105.
A composite tunnel lining system based on a sprayed waterproofing membrane combined with sprayed concrete is currently being considered for future Norwegian rail and road tunnels. Possible loading of the tunnel linings caused by water pressure is being investigated. This tunnel lining system consists of a waterproof membrane which, during application on the sprayed concrete lining, bonds mechanically to the sprayed concrete on either side. Hence, a continuous, sealing, and non-draining structure from the rock mass to the interior tunnel surface is formed in the walls and crown. Experiences from some successful recent projects with this lining system in Europe are reviewed. However, these experiences are not directly comparable to the Scandinavian hard rock tunnel lining approach, which utilizes a relatively thin sprayed and irregular concrete layer for permanent lining. When considering the sprayed membrane and sprayed concrete composite lining concept, introducing a partially sealing and undrained element in the lining, the experiences with the traditionally used lining systems in Norway need to be reconsidered and fully understood. A review of several hard rock tunnels with adverse conditions, in which the tunnel lining has been subject to load monitoring, shows that only very small loads in the tunnel linings occur. Recent investigations with in situ water pressure testing, including two sites with the composite sprayed membrane in a partially drained waterproof tunnel lining, are discussed. In a case with a cavern located in a hydraulically saturated rock mass subjected to approximately 8 bar hydrostatic pressure, a negative pressure gradient towards the tunnel lining has been measured. The investigation results from the Norwegian test sites indicate that no significant loading of the tunnel lining takes place in a hydraulically saturated rock when applying this composite waterproof tunnel lining in parts of the tunnel perimeter.  相似文献   
106.
Kleimann  Jens  Hornig  Gunnar 《Solar physics》2001,200(1-2):47-62
Magnetic flux tubes reaching from the solar convectivezone into the chromosphere have to pass through the relatively cool, and therefore non-ideal (i.e. resistive) photospheric region enclosed between the highly ideal sub-photospheric and chromospheric plasma. It is shown that stationary MHD equilibria of magnetic flux tubes which pass through this region require an inflow of photospheric material into the flux tube and a deviation from iso-rotation along the tube axis. This means that there is a difference in angular velocity of the plasma flow inside the tube below and above the non-ideal region. Both effects increase with decreasing cross section of the tube. Although for characteristic parameters of thick flux tubes the effect is negligible, a scaling law indicates its importance for small-scale structures. The relevance of this `inflow effect' for the expansion of flux tubes above the photosphere is discussed.  相似文献   
107.
Stimulus to reach the millennium goals of poverty abatement and empowerment, including education and employment, for the large part of the population in the coastal zone can be found in the resources and services of oceans and coasts; the required financial means, given political will and right priorities, can be provided through implementation of the related international conventions, in particular UNCLOS with the EEZ, the Common Heritage of Mankind and other provisions, Agenda 21 [1] of UNCED and the WSSD 2002 Ocean Targets; the motivation is the necessity to address over-exploitation, depletion and destruction of resources, habitats and coastal ecosystem services, global changes, as well as economic transformations and social conditions of poverty, employment and unequity. Achieving adequate management and protection of natural assets as ecosystems and their services, habitats, biodiversity requires that the socio-economic and human security needs of the coastal populations are met. One way to reach the goal is to enable them, representing about 50% of the global population and increasing, to fight poverty and cope with uncertainties and changing conditions of employment, environment and sustainability through proper governance of the coastal and ocean assets. This includes provision of education and knowledge as regards these assets and their proper uses. They include energy, water, food, transportation and trade, communication, coastal developments, tourism, recreation and ecosystem services, as well as the need to properly manage them.The present economic system cannot fully harmonize with the required governance, partly since the ecosystem resources and services are not internalised in the market-oriented system. This calls for a revised education and training system, more comprehensive than the present, taking into account the social, cultural and environmental requirements, and stressing the sustainable development paradigm. In order to achieve ocean governance and comprehensive human security an understanding of the system is needed. This is substantiated through the Decade of Education for Sustainable Development as well as the Millennium Ecosystem Assessment.The aim here is to discuss some of the issues in context of implementation of related ocean conventions and commitments, which include achieving ocean governance, and to elucidate opportunities given by oceans and coasts, also in generating employment and providing for basic human needs.  相似文献   
108.
With advancing climate change there is a growing need to include short-lived climate forcings in cost-efficient mitigation strategies to achieve international climate policy targets. Tools are required to compare the climate impact of perturbations with distinctively different atmospheric lifetimes and atmospheric properties. We present a generic approach for relating the climate effect of short-lived climate forcers (SLCF) to that of CO2 emissions. We distinguish between three alternative types of metric-based factors that can be used to derive CO2 equivalences for SLCF: based on forcing, activity and fossil fuel consumption. We derive numerical values for a wide range of parameter assumptions and apply the resulting generalised approach to the practical example of aviation-induced cloudiness. The evaluation of CO2 equivalences for SLCF tends to be more sensitive to SLCF specific physical uncertainties and the normative choice of a discount rate than to the choice of a physical or economic metric approach. The ability of physical metrics to approximate economic-based metrics alters with changing atmospheric concentration levels and trends. Under reference conditions, physical CO2 equivalences for SLCF provide sufficient proxies for economic ones. The latter, however, allow detailed insight into structural uncertainties. They provide CO2 equivalences for SLCF in short term strategies in the face of failing climate policies, and a temporal evolution of CO2 equivalences over time that is noticeably better in line with cost-efficient climate stabilisation.  相似文献   
109.
An analysis of the Mariner 10 dual frequency radio occultation recordings has yielded new information on the radius and atmosphere of Mercury. The ingress measurements which were conducted near 1.1° North latitude and 67.4° East longitude on the night side of the planet, gave a value for the radius of 2439.5 ± 1 km. Egress near 67.6° North latitide and 258.4° East longitude in the sunlit side yielded a radius of 2439.0 ± 1 km. The atmospheric measurements showed the electron density to be less than 103 cm?3 on both sides of the planet. From the latter result one may infer an upper limit to the dayside surface gas density of 106 molecules per cm3.  相似文献   
110.
The Loop meteorite was found in 1962 in Gaines County, Texas, at a location very close to that where the Ashmore chondrite was found in 1969. The two specimens were assumed to be fragments of the same meteorite. The Loop meteorite is a type L6 chondrite composed of olivine (Fo75.4Fa24.6), orthopyroxene (En77.6Wo1.5Fs20.9), clinopyroxene (En47.5Wo45.1Fs7.4), plagioclase (Ab84.3Or5.5An10.2), Fe-Ni metal, troilite, and chromite. Fe-Ni metal is represented by kamacite (5.8-6.4 wt % Ni, 0.88-1.00 wt % Co), taenite (30.0–52.9 wt % Ni, 0.16-0.34 wt % Co), and plessite (16.8–28.5 wt % Ni, 0.38-0.54 wt % Co). Native copper occurs as rare inclusions in Fe-Ni metal. Both chondrules and matrix have similar mineral compositions. The mineral chemistry of the Loop meteorite is quite different from that of the Ashmore, which was classified as an H5 chondrite by Bryan and Kullerud (1975). Therefore, the Ashmore and Loop meteorites are two different chondrites, even though they were recovered from the same geographic location.  相似文献   
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