Spectral-element simulations of global seismic wave propagation—II. Three-dimensional models, oceans, rotation and self-gravitation     

Dimitri Komatitsch  Jeroen Tromp 《Geophysical Journal International》2002,150(1):303-318

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Primary minerals of Zn-Pb mining and metallurgical dumps and their environmental behavior at Plombières,Belgium     

H. Kucha  A. Martens  R. Ottenburgs  W. De Vos  W. Viaene 《Environmental Geology》1996,27(1):1-15

The primary phases and minerals of the Plombières dumps include typical smelting furnace products such as metallic Fe, Pb, Cu, Zn, Fe-Zn alloys, carbides, phosphides, sulfides of Fe, Zn, Pb, Cu, Mn (alabandite), and FeAs. Spinels, mainly of Fe and Al, are common constituents of the primary assemblage; substitution by Zn, V, Cr, Ti, Mg, and Ca occurs. Primary phases also include the most common Zn-rich fayalite, Zn-rich Ca-Fe silicates, melilite, corundum, and apatite. Most of the Zn is incorporated in iron silicates, ZnO and ZnS. Lead occurs mainly as PbS, metallic lead, and is also present in coal residues. Cadmium is found mainly in metallic zinc and its alloys and in ZnO. The dumps also contain mining wastes composed of pyrite, melnikovite, and iron oxides produced by natural weathering of Zn-Pb ores. Melnikovite and iron oxides are rich in As, Pb, and Zn and possess an increased content of Tl. Leaching tests carried out on the surfaces of polished sections indicate that acid rain (solutions I and II) will mobilize mainly Zn and Cd and, to a much smaller extent, Pb and Sb. Leaching of metals by sulfate-chloride fluids present in the pore network of dumps (solutions III, IV, and V) depends on the pH, which in the dumps is controlled by the proportion of carbonates to sulfides. The more acid fluids leach both sulfides and silicates.  相似文献   

Three-dimensional structure of the African superplume from waveform modelling   总被引：1，自引：0，他引：1  

Sidao Ni  Don V. Helmberger  Jeroen Tromp 《Geophysical Journal International》2005,161(2):283-294

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A New Generation Earth Mantle Model from Global Adjoint Tomography     

Youyi Ruan  Wenjie Lei  Matthieu Lefebvre  Ryan Modrak  James Smith  Ridvan Orsvuran  Ebru Bozdag  Judith Hill  Norbert Podhorszki  Dave Pugmire  Jeroen Tromp 《《地质学报》英文版》2018,92(Z1):140-140

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Perceived fairness and public acceptability of carbon pricing: a review of the literature     

Sara Maestre-Andrés  Stefan Drews  Jeroen van den Bergh 《Climate Policy》2019,19(9):1186-1204

While carbon pricing is widely seen as a crucial element of climate policy and has been implemented in many countries, it also has met with strong resistance. We provide a comprehensive overview of public perceptions of the fairness of carbon pricing and how these affect policy acceptability. To this end, we review evidence from empirical studies on how individuals judge personal, distributional and procedural aspects of carbon taxes and cap-and-trade. In addition, we examine preferences for particular redistributive and other uses of revenues generated by carbon pricing and their role in instrument acceptability. Our results indicate a high concern over distributional effects, particularly in relation to policy impacts on poor people, in turn reducing policy acceptability. In addition, people show little trust in the capacities of governments to put the revenues of carbon pricing to good use. Somewhat surprisingly, most studies do not indicate clear public preferences for using revenues to ensure fairer policy outcomes, notably by reducing its regressive effects. Instead, many people prefer using revenues for ‘environmental projects’ of various kinds. We end by providing recommendations for improving public acceptability of carbon pricing. One suggestion to increase policy acceptability is combining the redistribution of revenue to vulnerable groups with the funding for environmental projects, such as on renewable energy.

Key policy insights

• If people perceive carbon pricing instruments as fair, this increases policy acceptability and support.

• People’s satisfaction with information provided by the government about the policy instrument increases acceptability.

• While people express high concern over uneven distribution of the policy burden, they often prefer using carbon pricing revenues for environmental projects instead of compensation for inequitable outcomes.

• Recent studies find that people’s preferences shift to using revenues for making policy fairer if they better understand the functioning of carbon pricing, notably that relatively high prices of CO₂-intensive goods and services reduce their consumption.

• Combining the redistribution of revenue to support both vulnerable groups and environmental projects, such as on renewable energy, seems to most increase policy acceptability.

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Changing trust relations within the Dutch fishing industry: The case of National Study Groups     

Birgit I. de Vos  Arthur P.J. Mol 《Marine Policy》2010

This paper focuses on changing trust relationships among fishermen following new governance arrangements. The previous ‘thick’ trust relationships that characterized the Dutch fisheries industry under a neo-corporatist arrangement had resulted in an isolation of local fishermen groups vis-à-vis outsiders. However, under new governance arrangements, in particular the so-called Study Groups, these trust relationships are changing. The establishment of Study Groups, where fishermen from different localities have to cooperate on sustainability innovations in order to receive subsidies, lead to more diversity within the industry, more collaborations across localities and new forms of ‘thin’ trust. As such, these Study Groups can be understood as successful experiments in further opening up of the fisheries community.  相似文献   

Maslov theory for surface wave propagation on a laterally heterogeneous earth   总被引：1，自引：0，他引：1  

Jeroen Tromp  F. A. Dahlen 《Geophysical Journal International》1993,115(2):512-528

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The value of a physically based model versus an empirical approach in the prediction of ephemeral gully erosion for loess-derived soils   总被引：3，自引：0，他引：3  

Jeroen Nachtergaele  J. Poesen  A. Steegen  I. Takken  L. Beuselinck  L. Vandekerckhove  G. Govers 《Geomorphology》2001,40(3-4)

A data set on soil losses and controlling factors for 58 ephemeral gullies has been collected in the Belgian loess belt from March 1997 to March 1999. Of the observed ephemeral gullies, 32 developed at the end of winter or in early spring (winter gullies) and 26 ephemeral gullies developed during summer (summer gullies). The assessed data have been used to test the physically based Ephemeral Gully Erosion Model (EGEM) and to compare its performance with the value of simple topographical and morphological indices in the prediction of ephemeral gully erosion.Analysis shows that EGEM is not capable of predicting ephemeral gully cross-sections well. Although conditions for input parameter assessment were ideal, some parameters such as channel erodibility, critical flow shear stress and local rainfall depth showed great uncertainty. Rather than revealing EGEM's inability of predicting ephemeral gully erosion, this analysis stresses the problematic nature of physically based models, since they often require input parameters that are not available or can hardly be obtained.With respect to the value of simple topographical and morphological indices in predicting ephemeral gully erosion, this study shows that for winter gullies and summer gullies, respectively, over 80% and about 75% of the variation in ephemeral gully volume can be explained when ephemeral gully length is known. Moreover, when previously collected data for ephemeral gullies in two Mediterranean study areas and the data for summer gullies formed in the Belgian loess belt are pooled, it appears that one single length (L)–volume (V) relation exists (V=0.048 L^1.29; R²=0.91). These findings imply that predicting ephemeral gully length is a valuable alternative for the prediction of ephemeral gully volume. A simple procedure to predict ephemeral gully length based on topographical thresholds is presented here. Secondly, the empirical length–volume relation can also be used to convert ephemeral gully length data extracted from aerial photos into ephemeral gully volumes.  相似文献   

Latent heat effects of the major mantle phase transitions on low-angle subduction     

Jeroen van Hunen  Arie P van den Berg  Nico J Vlaar 《Earth and Planetary Science Letters》2001,190(3-4):125-135

Very low to zero shallow dip angles are observed at several moderately young subduction zones with an active trenchward moving overriding plate. We have investigated the effects of latent heat for this situation, where mantle material is pushed through the major mantle phase transitions during shallow low-angle subduction below the overriding plate. The significance of the buoyancy forces, arising from the latent heat effects, on the dynamics of the shallowly subducting slab is examined by numerical modeling. When a 32-Ma-old slab is overridden with 2.5 cm/yr by a continent, flat subduction occurs with a 4–5 cm/yr convergence rate. When latent heat is included in the model, forced downwellings cause a thermal anomaly and consequently thermal and phase buoyancy forces. Under these circumstances, the flat slab segment subducts horizontally about 350 km further and for about 11 Ma longer than in the case without latent heat, before it breaks through the 400-km phase transition. The style of subduction strongly depends on the mantle rheology: increasing the mantle viscosity by one order of magnitude can change the style of subduction from steep to shallow. Similarly, an overriding velocity of less than 1 cm/yr leads to steep subduction, which gradually changes to flat subduction when increasing the overriding velocity. However, these model parameters do not change the aforementioned effect of the latent heat, provided that low-angle subduction occurs. In all models latent heat resulted in a substantial increase of the flat slab length by 300–400 km. Varying the olivine–spinel transition Clapeyron slope γ from 1 to 6 MPa/K reveals a roughly linear relation between γ and the horizontal length of the slab. Based on these results, we conclude that buoyancy forces due to latent heat of phase transitions play an important role in low-angle subduction below an overriding plate.  相似文献   

Variational principles for surface wave propagation on a laterally heterogeneous Earth—II. Frequency-domain JWKB theory     

Jeroen Tromp  F. A. Dahlen 《Geophysical Journal International》1992,109(3):599-619

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