The P-wave upper mantle structure beneath an active spreading centre: the Gulf of California   总被引：1，自引：0，他引：1  

Marianne c. Walck 《Geophysical Journal International》1984,76(3):697-723

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Erratum to: Elemental Composition of Mnemiopsis leidyi A. Agassiz 1865 and Its Implications for Nutrient Recycling in a Long Island Estuary     

Marianne E. McNamara  Darcy J. Lonsdale  Robert C. Aller 《Estuaries and Coasts》2014,37(3):789-789

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The polarization of public concern about climate change in Norway     

Marianne Aasen 《Climate Policy》2013,13(2):213-230

This article contributes to the existing literature by investigating the importance of value orientations for the Norwegian public's climate change concern, by analysing data from a national Gallup Poll from 2003 to 2011. Logistic regressions were conducted to investigate the importance of individualistic and egalitarian values for climate concern, and whether the groups of different value orientations have polarized in their climate concern over time. Respondents who hold less individualistic values and those holding egalitarian values are found more likely to be concerned about climate change than are those holding individualistic and less egalitarian values. Furthermore, the analyses find polarization in climate concern in the period for both value orientations. Increased focus on policy instruments in the political debate may be one explanation for values being increasingly salient. Future research should focus on studying ways to formulate policies given variations in values. One way would be to develop solutions that have co-benefits across groups of different value orientations. However, not all mitigation policies have immediate co-benefits for everyone. Research on how changes in the institutional setting may enhance the logic of social responsibility seems crucial.

Policy relevance

It is an important social science contribution to increase our understanding of public positions on climate change for developing effective responses to this vexing problem. This study identifies polarization over time between subgroups of different value orientations in their climate change concern. This may have implications for policies, as political solutions may be increasingly dependent on the composition of political leadership. Society and politicians should look for mitigation policies that have co-benefits across groups of different value orientations when possible. However, not all mitigation policies have immediate co-benefits for everyone. One option then is to change the institutional settings from enhancing the logic of individual benefits to enhancing the logic of social benefits for behaviour crucial for mitigating climate change. Finally, narratives about a low-emitting society that are attractive for all groups of value orientations should be emphasized.  相似文献   

The large peculiar velocity of the cD galaxy in Abell 3653     

Kevin A. Pimbblet  Isaac G. Roseboom  Marianne T. Doyle 《Monthly notices of the Royal Astronomical Society》2006,368(2):651-658

We present a catalogue of galaxies in Abell 3653 from observations made with the 2-degree field (2dF) spectrograph at the Anglo-Australian Telescope. Of the 391 objects observed, we find 111 are bona fide members of Abell 3653. We show that the cluster has a velocity of   cz = 32 214 ± 83  km s⁻¹ ( z = 0.10 738 ± 0.00 027)  , with a velocity dispersion typical of rich, massive clusters of  σ _cz = 880⁺⁶⁶₋₅₄  . We find that the cD galaxy has a peculiar velocity of  683 ± 96  km s⁻¹  in the cluster rest frame – some 7σ away from the mean cluster velocity, making it one of the largest and most significant peculiar velocities found for a cD galaxy to date. We investigate the cluster for signs of substructure, but do not find any significant groupings on any length scale. We consider the implications of our findings on cD formation theories.  相似文献   

Analytical Solutions of Love Numbers for a Hydrostatic Ellipsoidal Incompressible Homogeneous Earth     

Marianne Greff-Lefftz  Laurent Métivier  Hilaire Legros 《Celestial Mechanics and Dynamical Astronomy》2005,93(1-4):113-146

Tidal forces acting on the Earth cause deformations and mass redistribution inside the planet involving surface motions and variation in the gravity field, which may be observed in geodetic experiments. Because for space geodesy it is now necessary to achieve the mm level in tidal displacements, we take into account the hydrostatic flattening of the Earth in the computation of the elasto-gravitational deformations. Analytical solutions are derived for the semi-diurnal tides on a slightly elliptical homogeneous incompressible elastic model. That simple analytical Earth’s model is not a realistic representation of any real planet, but it is useful to understand the physics of the problem and also to check numerical procedures. We rediscover and discuss the Love’s solutions and obtain new analytical solutions for the tangential displacement. We extend these analytical results to some geodetic responses of the Earth to tidal forces such as the perturbation of the surface gravity field, the tilt and the deviation of the vertical with reference to the Earth’s axis.  相似文献   

Diatom response to recent climatic change in a high arctic lake (Char Lake, Cornwallis Island, Nunavut)     

Neal Michelutti  Marianne S. V. Douglas  John P. Smol   《Global and Planetary Change》2003,38(3-4):257-271

From 1968 to 1972, Char Lake (Resolute Bay, Cornwallis Island, Canadian High Arctic) was the site of a large-scale limnological study conducted under the auspices of the International Biological Programme. However, since that time, very little research has been done on the lake. We sampled Char Lake from 1992 to 2000 for a suite of physical, chemical, and biological variables. In general, there were no major differences between our water quality data and those collected 30 years earlier, showing that Char Lake is still oligotrophic, slightly alkaline, and dilute. However, a diatom-based paleolimnological analysis revealed that a subtle, yet distinct species assemblage shift has occurred beginning around 1987. The timing of this species shift does not correspond to the deposition of atmospherically transported persistent organic pollutants into the lake (beginning in the early 1950s) or to minor disturbances within its catchment (early 1970s). Instead, these subtle diatom changes are consistent with recent climatic changes during 1988–1997 (as documented by local meteorological measurements), and are likely related to reduced summer ice cover and a longer growing season.  相似文献   

A volcanic activity alert-level system for aviation: review of its development and application in Alaska     

Guffanti  Marianne  Miller  Thomas P. 《Natural Hazards》2013,65(3):1519-1533

Avalanche warning services (AWS) are operated to protect communities and traffic lines in avalanche-prone regions of the Alps and other mountain ranges. In times of high avalanche danger, these services may decide to close roads or to evacuate settlements. Closing decisions are based on field observations, avalanche release statistics, and snow forecasts issued by weather services. Because of the spatial variability in the snowpack and the insufficient understanding of avalanche triggering mechanisms, closing decisions are characterized by large uncertainties and the information based on which AWS have to decide is always incomplete. In this paper, we illustrate how signal detection theory can be applied to make better use of the information at hand. The proposed framework allows the evaluation of past road closures and points to how the decision performance of AWS could be improved. To illustrate the proposed framework, we evaluate the decision performance of two AWS in Switzerland and discuss the advantages of such a formalized decision-making approach.  相似文献   

Changes in the Abundance and Species Composition of Phytoplankton in the Last 150 Years in the Southern Black Sea     

Erik Askov Mousing  Thorbjørn Joest Andersen  Marianne Ellegaard 《Estuaries and Coasts》2013,36(6):1206-1218

Changes in total abundance and in species composition of phytoplankton in the last 150 years in the southern Black Sea were investigated through a paleoecological study of two sediment cores. The results show changes in the species composition and a marked increase in total abundance of siliceous protists after around 1960. In core 22 (42°13.534′ N/36°29.555′ E), the dominating species before 1960 were Cyclotella choctawhatcheeana and Thalassiosira oestrupii. In core 25 (42°6.212′ N/36°37.460′ E), the dominating species before 1960 were T. oestrupii, Cyclotella meneghiniana, C. choctawhatcheeana, and Pseudosolenia cf. calcar-avis. Core 22 was located in closer proximity to the rim current than core 25, and the differences in total abundance between the cores could be related to differences in local nutrient loading prior to 1960. After around 1960, both cores changed to a community dominated by C. choctawhatcheeana. The changes in total abundance and species composition after around 1960 could be related to the increased nutrient loading from the Danube River into the rim current after the late 1960s. The results also showed changes in both total abundance and in species composition of dinoflagellate cysts. The dominating dinoflagellate cysts recorded were Lingulodinium polyedrum, Polykrikos schwartzii, and Spiniferites spp.  相似文献   

Mussel farming can be used as a mitigation tool--a reply     

Petersen JK  Timmermann K  Carlsson M  Holmer M  Maar M  Lindahl O 《Marine pollution bulletin》2012,64(2):452-4; author reply 455-6

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Numerical models of continental and submarine erosion: application to the northern Ligurian Margin (Southern Alps,France/Italy)          下载免费PDF全文

Carole Petit  Sébastien Migeon  Marianne Coste 《地球表面变化过程与地形》2015,40(5):681-695

We present a new numerical surface process model allowing us to take into account submarine erosion processes due either to submarine landslides or to hyperpycnal currents. A first set of models show that the frequency of hyperpycnal flows influences the development of submarine canyons at the mouth of continental rivers. Further experiments show that an increase in submarine slope leads to faster regressive canyon erosion and a more dentritic canyon network, whereas increasing the height of the unstable sediment pile located on the shelf break leads to wider and less dendritic canyons. The models are then applied to the western segment of the north Ligurian margin (northwestern Mediterranean), which displays numerous submarine canyons with various sizes and morphologies. From west to east, canyon longitudinal profiles as well as margin‐perpendicular profiles progressively change from moderately steep, concave‐up shapes to steeper linear to convex‐up shapes suggesting increasing eastward margin uplift. Moreover, the foot of the margin is affected by a marked slope increase with evidences of mass transport due to landslides. Numerical models which reproduce well the North Ligurian margin morphologic features indicate that the western part of the margin is submitted to rather low (i.e. 0.4 mm yr^?1) uplift and intense submarine erosion due to frequent hyperpycnal currents, whereas the eastern part bears more rapid (i.e. 0.7 mm yr^?1) uplift and has little or no hyperpycnal currents. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献