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41.
Katherine?CalvinEmail author Marshall?Wise Patrick?Luckow Page?Kyle Leon?Clarke Jae?Edmonds 《Climatic change》2016,136(1):57-68
The magnitude and character of the global resource base of fossil fuels is a key determinant of the evolution of the future global energy system and corresponding fossil fuel carbon emissions. What is less well understood is the potential magnitude of impact of the availability of fossil fuels, due to the interaction with biomass energy, on agriculture, land use, ecosystems and therefore carbon emissions from land-use change. This paper explores these links and implications. We show that if oil resources are limited, then the consequently higher price for liquids induces both the use of coal-to-liquids technology deployment, but also enhanced production of bioenergy crops particularly in a business-as-usual scenario. This in turn implies greater pressure to convert unmanaged ecosystems to produce bioenergy, and higher rates of terrestrial carbon emissions from land use. 相似文献
42.
Cathyrn A. Manduca Leon T. Silver Hugh P. Taylor 《Contributions to Mineralogy and Petrology》1992,109(3):355-372
A spatially abrupt geochemical boundary is preserved within four plutonic complexes along the western margin of the Cretaceous Idaho Batholith near McCall, Idaho. These intrusives ranging in composition from tonalite to granite were emplaced across a regional boundary between accreted oceanic-arc terranes and the continental margin, and their isotopic, major-element, and trace-element geochemistry provide detailed information about this change in crustal characteristics at depth, indicating that the boundary is nearly vertical and extends deep into the lithosphere. The Hazard Creek complex, emplaced west of the transition in wall-rock lithology, has initial 87Sr/86Sr (Ri) less than 0.7045 and 18O greater than 7.5, indicating little or no continental crust in its source region; however, elevated 18O requires some incorporation of rocks formed or altered at the earth's surface. A large shift in Ri and 18O is observed across the 5–8 km wide Little Goose Creek complex, which was emplaced across the wall-rock boundary. This is interpreted as mixing between: (1) a basaltic or andesitic magma with low K2O and high Na2O, Al2O3, and Sr, similar to that forming the Hazard Creek complex; and (2) materials similar to Precambrian sedimentary sedimentary rocks with low Sr, high 18O (+15) and high Ri (0.83 at 100 Ma). The Payette River complex, emplaced east of the wall-rock boundary, exhibits at least one additional component with low 18O (+6), moderate Ri (0.708) and mafic composition. This component is inferred to be old basaltic material in the lower crust or upper mantle similar to that inferred to be a minor part of the Peninsular Ranges Batholith in SE California (Silver et al. 1979; Hill et al. 1986). The easternmost complex in the Idaho transect is made up of granites that may contain a component of granitic cratonal basement. The entire west-to-east geochemical transition from oceanic-arc magmas to cratonal magmas takes place over a lateral distance of less than 20 km. Although the zone of transitional protolith dominated by metasedimentary rocks is unusually narrow and may have been in part tectonically removed, the striking geochemical similarities between this traverse and several other transects across much broader areas of Nevada and California suggest that the craton itself was not rifted apart, but that juxtaposition of the accreted oceanic-arc terranes occurred along the preexisting craton margin. The data confirm that the isotopic geochemistry of granitoid plutons can be used as a probe of deep lithospheric character, and that major lateral variations in the lithosphere on the order of one to two kilometers in width can be recognized in favorable circumstances. 相似文献
43.
Abstract The method of stochastic interpolation (conditional simulation) is introduced as a means to interpolate / extrapolate a scalar or vector field of an oceanic variable, e.g. currents. Conditional simulation produces the synthesis of a random field that is forced to agree with simultaneous measurements in the same time interval and area where the input data are being synthesized. The conditional simulation is applied to the vector field for two California current measurement programs (Coastal Ocean Dynamics Experiment (CODE) and Central California Coastal Circulation Study fccccsj, north and south of San Francisco, respectively). These field programs covered different areas and were characterized by different instrument spacings. The influence of these spatial factors shows up in the quality of the conditional simulations, i.e. a smaller area and a tighter mooring array led to more physically reasonable flow realizations. The various realizations provided by a series of conditional simulations allow confidence intervals to be defined. Other uses for this technique include optimization of current‐meter (or other sensor) placement and the specification of initial or boundary conditions for numerical models. This latter function could be invoked when real data are sparse or when the data that are available are overly smooth and do not contain enough of the variability of the natural system. 相似文献
44.
45.
Hang Lei Gao YuFeng He Jia Li Chi Zhou YunDong van Paassen Leon A. 《Acta Geotechnica》2022,17(12):5429-5439
Acta Geotechnica - In the biocement–geosynthetic system, biocement is combined with geosynthetic to increase the pullout resistance of the geosynthetic and thereby the stability of reinforced... 相似文献
46.
The paper describes a model, which estimates the risk levels of individual crude oil tankers. The intended use of the model, which is ready for trial implementation at The Norwegian Coastal Administrations new Vard? VTS (Vessel Traffic Service) centre, is to facilitate the comparison of ships and to support a risk based decision on which ships to focus attention on. For a VTS operator, tasked with monitoring hundreds of ships, this is a valuable decision support tool. The model answers the question, "Which ships are likely to produce an oil spill accident, and how much is it likely to spill?". 相似文献
47.
Rajat M. Thomas Saleem Zaroubi Benedetta Ciardi reas H. Pawlik Panagiotis Labropoulos Vibor Jeli Gianni Bernardi Michiel A. Brentjens A. G. de Bruyn Geraint J. A. Harker Leon V. E. Koopmans Garrelt Mellema V. N. Pandey Joop Schaye Sarod Yatawatta 《Monthly notices of the Royal Astronomical Society》2009,393(1):32-48
48.
Geraint Harker Saleem Zaroubi Gianni Bernardi Michiel A. Brentjens A. G. de Bruyn Benedetta Ciardi Vibor Jeli Leon V. E. Koopmans Panagiotis Labropoulos Garrelt Mellema ré Offringa V. N. Pandey Joop Schaye Rajat M. Thomas Sarod Yatawatta 《Monthly notices of the Royal Astronomical Society》2009,397(2):1138-1152
49.
Integrated estimates of global terrestrial carbon sequestration 总被引:1,自引:0,他引:1
Allison M. Thomson R. Csar Izaurralde Steven J. Smith Leon E. Clarke 《Global Environmental Change》2008,18(1):192-203
Assessing the contribution of terrestrial carbon sequestration to climate change mitigation requires integration across scientific and disciplinary boundaries. A comprehensive analysis incorporating ecologic, geographic and economic data was used to develop terrestrial carbon sequestration estimates for agricultural soil carbon, reforestation and pasture management. These estimates were applied in the MiniCAM integrated assessment model to evaluate mitigation strategies within policy and technology scenarios aimed at achieving atmospheric greenhouse gas stabilization by 2100. Terrestrial sequestration reaches a peak rate of 0.5–0.7 GtC yr−1 in mid-century with contributions from agricultural soils (0.21 GtC yr−1), reforestation (0.31 GtC yr−1) and pasture (0.15 GtC yr−1). Sequestration rates vary over time and with different technology and policy scenarios. The combined contribution of terrestrial sequestration over the next century ranges from 23 to 41 GtC. 相似文献
50.
Leon Sheleff 《GeoJournal》2001,53(3):297-309
Jewish tradition refers to the city of Jerusalem in both abstract and concrete terms, celestial Jerusalem and earthly Jerusalem. The two are intricately bound up with each other and Jerusalem, the eternal capital city of the Jewish people, derives its powerful mystique, from its original appearance in Jewish history, although Biblical Jerusalem, the ancient city surrounded by hills, and modern Jerusalem, the capital city of Israel, surrounded by satellite urban appendages, lack geographical congruity. In general, this is geo-politically relevant given the potent sensitivities that most Jews in Israel and elsewhere have for the symbolic value of their ancient capital. Significantly, most of the Arab inhabitants the capital city of Israel, are not Israeli citizens and the vast majority of them refuse to participate in municipal elections, even though Israeli law allows non-citizens who are permanent residents to vote in local elections. That Israel permits several countries to maintain separate consulates, in the western and eastern parts of Israel's capital, indicates Israel's implicit recognition of a dual status in Jerusalem. After the 1967 war, while careful to avoid using the formal language of annexation, Israel generally considered that east Jerusalem and some surrounding areas had become part of Israel, when by Basic Law: Jerusalem, the Capital City, it was declared to be the united and eternal capital of the State of Israel. This paper examines these political and legal developments. 相似文献