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31.
32.
Towards a 4D topographic view of the Norwegian sea margin 总被引:1,自引:1,他引:0
Morten Smelror John Dehls Jrg Ebbing Eiliv Larsen Erik R. Lundin
ystein Nordgulen Per Terje Osmundsen Odleiv Olesen Dag Ottesen Christophe Pascal Thomas F. Redfield Leif Rise 《Global and Planetary Change》2007,58(1-4):382
The present-day topography/bathymetry of the Norwegian mainland and passive margin is a product of complex interactions between large-scale tectonomagmatic and climatic processes that can be traced back in time to the Late Silurian Caledonian Orogeny. The isostatic balance of the crust and lithosphere was clearly influenced by orogenic thickening during the Caledonian Orogeny, but was soon affected by post-orogenic collapse including overprinting of the mountain root, and was subsequently affected by a number of discrete extensional events eventually leading to continental break-up in Early Eocene time. In the mid-Jurassic the land areas experienced deep erosion in the warm and humid climate, forming a regional paleic surface. Rift episodes in the Late Jurassic and Early Cretaceous, with differential uplift along major fault zones, led to more pronounced topographic contrasts during the Cretaceous, and thick sequences of clastic sediments accumulated in the subsiding basins on the shelf. Following renewed extension in the Late Cretaceous, a new paleic surface developed in the Paleocene. Following break-up the margin has largely subsided thermally, but several Cenozoic shortening events have generated positive contraction structures. On the western side of the on-shore drainage divide, deeper erosion took place along pre-existing weakness zones, creating the template of the present day valleys and fjords. In the Neogene the mainland and large portions of the Barents Sea were uplifted. It appears that this uplift permitted ice caps to nucleate and accumulate during the Late Pliocene northern hemisphere climatic deterioration. The Late Pliocene to Pleistocene glacial erosion caused huge sediment aprons to be shed on to the Norwegian Sea and Barents Sea margins. Upon removal of the ice load the landmass adjusted isostatically, and this still continues today. 相似文献
33.
If we are to limit global warming to 2 °C, all sectors in all countries must reduce their emissions of GHGs to zero not later than 2060–2080. Zero-emission options have been less explored and are less developed in the energy-intensive basic materials industries than in other sectors. Current climate policies have not yet motivated major efforts to decarbonize this sector, and it has been largely protected from climate policy due to the perceived risks of carbon leakage and a focus on short-term reduction targets to 2020. We argue that the future global climate policy regime must develop along three interlinked and strategic lines to facilitate a deep decarbonization of energy-intensive industries. First, the principle of common but differentiated responsibility must be reinterpreted to allow for a dialogue on fairness and the right to development in relation to industry. Second, a greater focus on the development, deployment and transfer of technology in this sector is called for. Third, the potential conflicts between current free trade regimes and motivated industrial policies for deep decarbonization must be resolved. One way forward is to revisit the idea of sectoral approaches with a broader scope, including not only emission reductions, but recognizing the full complexity of low-carbon transitions in energy-intensive industries. A new approach could engage industrial stakeholders, support technology research, development and demonstration and facilitate deployment through reducing the risk for investors. The Paris Agreement allows the idea of sectoral approaches to be revisited in the interests of reaching our common climate goals.Policy relevanceDeep decarbonization of energy-intensive industries will be necessary to meet the 2 °C target. This requires major innovation efforts over a long period. Energy-intensive industries face unique challenges from both innovation and technical perspectives due to the large scale of facilities, the character of their global markets and the potentially high mitigation costs. This article addresses these challenges and discusses ways in which the global climate policy framework should be developed after the Paris Agreement to better support transformative change in the energy-intensive industries. 相似文献
34.
35.
Comparison of the observed solar far ultraviolet irradiance and the observed solar sector structure during 1969 through 1972 shows a tendency for EUV maxima to be located near sector boundaries. 相似文献
36.
Analysis of the green line corona for the interval 1947–1970 suggests the existence of largescale organization of the emission. The green line emission at high northern latitudes (≈ 40°–60°) is correlated with the emission at high southern latitudes 6, 15 and 24 days later, while the low latitude green corona seems to be correlated on both sides of the equator with no time lag. These coronal features are recurrent with a 27-day period at all latitudes between ± 60 °, and we associate these large-scale structures with the solar magnetic sector structure. The high correlation between northern and southern high-latitude emission at 15 days time lag is explained as a signature of a two-sector structure, while four sectors are associated with the 6 and 24 day peaks. 相似文献
37.
A phenomenological model of the interplay between the polar magnetic fields of the Sun and the solar sector structure is discussed. Current sheets separate regions of opposite polarity and mark the sector boundaries in the corona. The sheets are visible as helmet streamers. The solar sector boundary is tilted with respect to central meridian, and boundaries with opposite polarity change are oppositely tilted. The tilt of a given type of boundary [(+, ?) or (?, +)] changes systematically during the sunspot cycle as the polarity of the polar fields reverses. Similar reversals of the position of the streamers at the limbs takes place. If we consider (a) a sunspot cycle where the northern polar field is inward (?) during the early part of the cycle and (b) a (+, ?) sector boundary at central meridian then the model predicts the following pattern; a streamer at high northern latitudes should be observed over the west limb together with a corresponding southern streamer over the east limb. The current sheet runs now NW-SE. At sunspot maximum the boundary is more in the N-S direction; later when the polar fields have completed their reversal the boundary runs NE-SW and the northern streamer should be observed over the east limb and the southern streamer over the west limb. Observational evidence in support of the model is presented, especially the findings of Hansen, Sawyer and Hansen and Koomen and Howard that the K-corona is highly structured and related to the solar sector structure. 相似文献
38.
Using resistivity measurements for dam safety evaluation at Enemossen tailings dam in southern Sweden 总被引:1,自引:0,他引:1
Internal erosion is a major reason for embankment dam failures. Resistivity measurements is an essentially non-destructive technique, which may have the possibility of detecting internal erosion processes and anomalous seepage at an early stage before the safety of the dam is at stake. This paper presents results from part of a dam safety investigation conducted at the Enemossen tailings dam in southern Sweden. Longitudinal resistivity sections, 2D measurements along the dam crest, provided an overview of the whole dam and served to detect anomalous zones. In selected areas, additional cross-sectional 2D surveys gave detailed information about the geo-electrical situations in the embankments. This information is valuable for similar investigations as information about resistivity in embankment construction material is scarce. Known problem areas were associated with low resistivities, even though the resistivity measurements alone did not provide enough information to confidently come to a decision about the status of the dams.
相似文献
S. JohanssonEmail: |
39.
The formation of the ion pairs MgSO4 and NaSO4? was investigated calorimetrically at 0.75 M ionic strength, 25°C, 1 atm. Simultaneous determinations of enthalpy changes, ΔH10, and stability constants, K1, were not possible, and values of K1 determined independently had to be introduced for the calculation of ΔH10. The values of ΔH10 obtained were 1–3 kJ mol?1 for MgSO4 and 0 kJ mol?1 for NaSO4?. 相似文献
40.
Growth Rates of Global Energy Systems and Future Outlooks 总被引:1,自引:0,他引:1
The world is interconnected and powered by a number of global energy systems using fossil, nuclear, or renewable energy. This
study reviews historical time series of energy production and growth for various energy sources. It compiles a theoretical
and empirical foundation for understanding the behaviour underlying global energy systems’ growth. The most extreme growth
rates are found in fossil fuels. The presence of scaling behaviour, i.e. proportionality between growth rate and size, is
established. The findings are used to investigate the consistency of several long-range scenarios expecting rapid growth for
future energy systems. The validity of such projections is questioned, based on past experience. Finally, it is found that
even if new energy systems undergo a rapid ‘oil boom’-development—i.e. they mimic the most extreme historical events—their
contribution to global energy supply by 2050 will be marginal. 相似文献