Free oscillations of a spherical anelastic earth     

Jeroen Tromp  F. A. Dahlen 《Geophysical Journal International》1990,103(3):707-723

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Local empowerment through economic restructuring in Brazil: the case of the greater ABC region     

Andrs Rodríguez-Pose  John Tomaney  Jeroen Klink 《Geoforum》2001,32(4):1

Regional and local capacity building in Brazil, as in other Latin American countries, has traditionally been linked with democracy. Whereas periods of dictatorship usually saw the establishment of a tight grip by the centre over state and local governments, democracy has been linked to greater autonomy at the regional and local levels. The revival of regional and local governments in Brazil over the last decade and a half seems to fall into this latter category. In this paper we will argue that the advent of democracy is however not the only factor behind the recent dynamism at the sub-national level, but that economic restructuring is becoming a major force behind the adoption of more pro-active attitudes and policies by local and regional governments. We will illustrate this theory with the example of the greater ABC region, in the São Paulo metropolitan area, where economic crisis and restructuring has led to inter-municipal co-operation and the creation of a local economic development council.  相似文献   

Reconstructing 20thcentury lead pollution andsediment focusing in a peat land pool (Kempen, Belgium), via 210Pbdating     

Jeroen E. Sonke  William C. Burnett  Jurian A. Hoogewerff  Sieger R. van der Laan  Jaco Vangronsveld  D. Reide Corbett 《Journal of Paleolimnology》2003,29(1):95-107

Pb-210 dating of two metal-polluted organic sedimentcores obtained near a former pyrometallurgical zinc smelter in Lommel, Belgiumhave been used to reconstruct atmospheric lead deposition rates during the20^th century. Independent knowledge concerning historical pollutionevents and ¹³⁷Cs fall-out profiles has allowed a criticalevaluation of the CRS, CIC and CF-CS models for the ²¹⁰Pb ageinterpretation. Resulting ages for the three models suggest that, in this case,the CIC model gives the most accurate interpretation of historical pollutionevents and atmospheric lead fall-out. The ²¹⁰Pbwater-sediment flux was estimated at 141–1158Bq·m^–2·yr^–1 for one site and62–106 Bq·m^–2·yr^–1 at theother site, during the last century. The large difference illustrates thatsediment focusing was important on a small spatial scale (10 m).The direction of focusing correlates with the predominant wind direction.Maximum atmospheric lead deposition rates were found to be 1.63 ± 0.59g·m^–2·yr^–1 around 1968 AD,which is 2 orders of magnitude larger than the Belgian average in 1980 AD, and5 orders larger than Holocene atmospheric lead deposition.  相似文献   

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

Jeroen Tromp  F. A. Dahlen 《Geophysical Journal International》1992,109(3):581-598

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Valueloading And Uncertainty In A Sector-based Differentiation Scheme For Emission Allowances     

Heleen Groenenberg  Jeroen Van Der Sluijs 《Climatic change》2005,71(1-2):75-115

The Triptych approach is a sectoral approach for differentiation of quantitative greenhouse gas emission reduction objectives. In this study we investigate the ranges in emission reduction targets that result from differences in valueladen assumptions and uncertainties in input data and parameters. In order to assess the effect of highly valueladen assumptions on resulting objectives we used two approaches. First we performed a sensitivity analysis. Then we elaborated the approach from four ideal-typical value-orientations: the administrator, the businessman, the campaigner and the survivor. For each of these value-orientations we specified corresponding sets of assumptions of highly valueladen parameters. Within each set, we also assessed uncertainties for the remaining parameters and input data. We assessed the strength and we quantified their inexactnesses with probability distribution functions. Next, we carried out Monte Carlo simulations in each of the four value-orientations to quantify error propagation from the inexactnesses in input data and parameters. We found targets for the year 2015 for Annex I countries differed up to around 20%-points over the four value-orientations. For developing countries differences in allowances were found up to the order of four. In addition, results are affected to a large extent by uncertainties in the other input data and parameters. Ranges in the outcome resulting from uncertainties are between 10 and 35%-points for Annex I countries, depending on the value-orientation chosen and between 20 and 120%-points for non-Annex I countries. However, the ranking of countries within the calculated differentiation remains roughly the same, an exception being the ranking that resulted from the businessman’s perspective. Other consistent combinations of valueladen assumptions may result in objectives that are outside the range that we based on the four value-orientations. We concluded that care should be taken when assessing valueloading in calculations schemes for emissions objectives based on a limited number of value-orientations only. Our analysis clearly underlines the relevance of making explicit policy variables in schemes for the differentiation of commitments. It is necessary to reach consensus on these variables if such schemes are to support negotiations on greenhouse gas emissions allowances.  相似文献   

Seismic tomography, adjoint methods, time reversal and banana-doughnut kernels   总被引：5，自引：0，他引：5  

Jeroen Tromp  Carl Tape  Qinya Liu 《Geophysical Journal International》2005,160(1):195-216

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Depositional facies and stratal geometry of an Upper Carboniferous prograding and aggrading high-relief carbonate platform (Cantabrian Mountains, N Spain)   总被引：1，自引：0，他引：1  

Giovanna Della Porta  Jeroen A. M. Kenter  Juan R. Bahamonde† 《Sedimentology》2004,51(2):267-295

Seismic‐scale continuous exposures of an Upper Carboniferous (Bashkirian–Moscovian) carbonate platform (N Spain) provide detailed information about the lithofacies and stratal geometries (quantified with differential global positioning system measurements) of microbial boundstone‐dominated, steep prograding and aggrading platform margins. Progradational and aggradational platform‐to‐slope transects are characterized by distinct lithological features and stratal patterns that can be applied to the understanding of geometrically comparable, high‐relief depositional systems. The Bashkirian is characterized by rapid progradation at rates of 415–970 m My^?1. Characteristic outer‐platform facies are high‐energy grainstones with coated intraclasts, ooids and pisoids, moderate‐energy algal‐skeletal grainstones to packstones and lower energy algal packstone and boundstone units. The Moscovian aggradational phase is characterized by aggradation rates of 108 m My^?1. Coated‐grain shoals are less common, whereas crinoidal bars nucleated in well‐circulated settings below wave‐base. Boundstones form a belt (30–300 m wide) at the platform break and interfinger inwards with massive algal‐skeletal wackestones (mud‐rich banks). The progradational phase has divergent outer‐platform strata with basinward dips of 12° to 2°. Steep clinoforms with dips of 20–28° are 650–750 m in relief and possibly sigmoidal to concave in the lower part. The basinward‐dipping outer‐platform strata might be depositional for less than 6°, consistent with lithofacies deepening seaward. The basinward dip is attributed to the downward shift of upper‐slope boundstone, forced by late highstand and relative sea‐level fall, and to compaction‐induced differential subsidence during progradation. The aggradational phase is characterized by horizontally layered platform strata. Clinoforms steepen to 30–45° reaching heights of 850 m and are planar to concave. The evolution from progradation to aggradation, at the Bashkirian–Moscovian boundary, is attributed to increased foreland‐basin subsidence and decreased boundstone accumulation rates. Progradation was primarily controlled by boundstone growth rather than by highstand shedding from the platform top. Within the major phases, aggradational–progradational increments are produced by third‐ to fourth‐order relative sea‐level fluctuations.  相似文献   

A Coupled Local-Mode Analysis of Surface-Wave Propagation In A Laterally Heterogeneous Waveguide     

Jeroen Tromp 《Geophysical Journal International》1994,117(1):153-161

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Lanthanide-humic substances complexation. I. Experimental evidence for a lanthanide contraction effect     

Jeroen E. Sonke  Vincent J.M. Salters 《Geochimica et cosmochimica acta》2006,70(6):1495-1506

The interaction of the lanthanides (Ln) with humic substances (HS) was investigated with a novel chemical speciation tool, Capillary Electrophoresis-Inductively Coupled Plasma Mass Spectrometry (CE-ICP-MS). By using an EDTA-ligand competition method, a bi-modal species distribution of LnEDTA and LnHS is attained, separated by CE, and detected online by sector field ICP-MS. We quantified the binding of all 14 rare earth elements (REEs), Sc and Y with Suwannee river fulvic acid, Leonardite coal humic acid, and Elliot soil humic acid under environmental conditions (pH 6-9, 0.001-0.1 mol L⁻¹ NaNO₃, 1-1000 nmol L⁻¹ Ln, 10-20 mg L⁻¹ HS). Conditional binding constants for REE-HS interaction (K_c) ranged from 8.9 < log K_c < 16.5 under all experimental conditions, and display a lanthanide contraction effect, Δ_LK_c: a gradual increase in K_c from La to Lu by 2-3 orders of magnitude as a function of decreasing ionic radius. HS polyelectrolyte effects cause K_c to increase with increasing pH and decreasing ionic strength. Δ_LK_c increases significantly with increasing pH, and likely with decreasing ionic strength. Based on a strong correlation between Δ_LK_c values and denticity for organic acids, we suggest that HS form a range of tri- to tetra-dentate complexes under environmental conditions. These results confirm HS to be a strong complexing agent for Ln, and show rigorous experimental evidence for potential REE fractionation by HS complexation.  相似文献   

A framework for dealing with uncertainty due to model structure error     

Jens Christian Refsgaard  Jeroen P. van der Sluijs  James Brown  Peter van der Keur 《Advances in water resources》2006

Although uncertainty about structures of environmental models (conceptual uncertainty) is often acknowledged to be the main source of uncertainty in model predictions, it is rarely considered in environmental modelling. Rather, formal uncertainty analyses have traditionally focused on model parameters and input data as the principal source of uncertainty in model predictions. The traditional approach to model uncertainty analysis, which considers only a single conceptual model, may fail to adequately sample the relevant space of plausible conceptual models. As such, it is prone to modelling bias and underestimation of predictive uncertainty.  相似文献