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41.
Emil Jeansson Sara Jutterström Leif G. Anderson E. Peter Jones James H. Swift 《Progress in Oceanography》2008,78(1):12-28
Data from the East Greenland Current in 2002 are evaluated using optimum multiparameter analysis. The current is followed from north of Fram Strait to the Denmark Strait Sill and the contributions of different source waters, in mass fractions, are deduced. From the results it can be concluded that, at least in spring 2002, the East Greenland Current was the main source for the waters found at the Denmark Strait Sill, contributing to the overflow into the North Atlantic. The East Greenland Current carried water masses from different source regions in the Arctic Ocean, the West Spitsbergen Current and the Greenland Sea. The results agree well with the known circulation of the western Nordic Seas but also add knowledge both to the quantification and to the mixing processes, showing the importance of the locally formed Greenland Sea Arctic Intermediate Water for the East Greenland Current and the Denmark Strait. 相似文献
42.
43.
Emil Wolf 《Astrophysics and Space Science》1995,227(1-2):277-297
This article is essentially the text of lectures presented September 7, 1982 at the Max Born Centenary Conference held in Edinburgh, Scotland and October 21, 1982 at the Max Born Symposium held during the Annual Meeting of the Optical Society of America.Emil Wolf is Wilson Professor of Optical Physics at the University of Rochester. Reprinted fromOptics News, November/December 1983 with permisssion from the author and the Optical Society of America 相似文献
44.
45.
Emil Blias 《Geophysical Prospecting》2013,61(3):574-581
I introduce a new explicit form of vertical seismic profile (VSP) traveltime approximation for a 2D model with non‐horizontal boundaries and anisotropic layers. The goal of the new approximation is to dramatically decrease the cost of time calculations by reducing the number of calculated rays in a complex multi‐layered anisotropic model for VSP walkaway data with many sources. This traveltime approximation extends the generalized moveout approximation proposed by Fomel and Stovas. The new equation is designed for borehole seismic geometry where the receivers are placed in a well while the sources are on the surface. For this, the time‐offset function is presented as a sum of odd and even functions. Coefficients in this approximation are determined by calculating the traveltime and its first‐ and second‐order derivatives at five specific rays. Once these coefficients are determined, the traveltimes at other rays are calculated by this approximation. Testing this new approximation on a 2D anisotropic model with dipping boundaries shows its very high accuracy for offsets three times the reflector depths. The new approximation can be used for 2D anisotropic models with tilted symmetry axes for practical VSP geometry calculations. The new explicit approximation eliminates the need of massive ray tracing in a complicated velocity model for multi‐source VSP surveys. This method is designed not for NMO correction but for replacing conventional ray tracing for time calculations. 相似文献
46.
Alexander Barth Aida Alvera-Azcárate Jean-Marie Beckers Joanna Staneva Emil V. Stanev Johannes Schulz-Stellenfleth 《Ocean Dynamics》2011,61(5):599-610
Surface winds are crucial for accurately modeling the surface circulation in the coastal ocean. In the present work, high-frequency
radar surface currents are assimilated using an ensemble scheme which aims to obtain improved surface winds taking into account
European Centre for Medium-Range Weather Forecasts winds as a first guess and surface current measurements. The objective
of this study is to show that wind forcing can be improved using an approach similar to parameter estimation in ensemble data
assimilation. Like variational assimilation schemes, the method provides an improved wind field based on surface current measurements.
However, the technique does not require an adjoint, and it is thus easier to implement. In addition, it does not rely on a
linearization of the model dynamics. The method is validated directly by comparing the analyzed wind speed to independent
in situ measurements and indirectly by assessing the impact of the corrected winds on model sea surface temperature (SST)
relative to satellite SST. 相似文献
47.
Emil Erjavec Tina Volk Miroslav Rednak Barbara Zagorc Ben Moljk 《Climate Policy》2013,13(8):1014-1030
This article analyses the interactions between agricultural policy measures in the EU and the factors affecting GHG emissions from agriculture on the one hand, and the adaptation of agriculture to climate change on the other. To this end, the article uses Slovenia as a case study, assessing the extent to which Slovenian agricultural policy is responding to the challenges of climate change. All agricultural policy measures related to the 2007–2013 programming period were analysed according to a new methodological approach that is based on a qualitative (expert evaluation) and a quantitative (budgetary transfers validation) assessment. A panel of experts reached consensus on the key factors through which individual measures affect climate change, in which direction and how significantly. Data on budgetary funds for each measure were used as weights to assess their relative importance. The results show that there are not many measures in (Slovenian) agricultural policy that are directly aimed at reducing GHG emissions from agriculture or at adaptation to climate change. Nevertheless, most affect climate change, and their impact is far from negligible. Current measures have both positive and negative impacts, but overall the positive impacts prevail. Measures that involve many beneficiaries and more budgetary funds had the strongest impact on aggregate assessments. In light of climate change, agricultural policy should pay more attention to measures that are aimed at raising the efficiency of animal production, as it is the principal source of GHG emissions from agriculture.Policy relevanceAgricultural policy must respond to climate challenges and climate change impact assessment must be included in the process of forming European agricultural policy. Agricultural policy measures that contribute to the reduction of emissions and adaptation, whilst acting in synergy with other environmental, economic and social goals, should be promoted. The approach used in this study combines qualitative and quantitative data, yielding an objective assessment of the climate impact of agricultural policy measures and providing policy makers with a tool for either ex ante or ex post evaluations of climate-relevant policy measures. 相似文献
48.
Questions of justice have been raised in recent years when contending with the social costs of urban sprawl. But this field of inquiry suffers from the difficulty of translating the abstract notion of justice into measurable spatial indices. The aim of this paper is to empirically measure the liberal notion of justice in the metropolitan region of Tel Aviv by adopting Pierre Bourdieu’s theory of three forms of capital. Under this theory, the formation of economic, cultural, and social capital in the individual’s living environment determines the person’s exposure to different sets of life-chances (i.e., capabilities), thus influencing equality of opportunity (i.e., social justice) in space. The analysis reveals that suburban inhabitants benefit from a larger accumulation of the three forms of capital than do urban inhabitants. Accumulation of these capitals has a positive effect on exposure to life-chances, thus enhancing spatial segregation between cities and suburbs. 相似文献
49.
Vulnerability, hazards and multiple risk assessment for Georgia 总被引:2,自引:1,他引:1
50.
Emil Makovicky 《Mineralogy and Petrology》2012,106(1-2):19-24