Taming global flood disasters. Lessons learned from Dutch experience   总被引：1，自引：1，他引：0  

Chris Zevenbergen  Sebastiaan van Herk  Jeroen Rijke  Pavel Kabat  Pieter Bloemen  Richard Ashley  Andrew Speers  Berry Gersonius  William Veerbeek 《Natural Hazards》2013,65(3):1217-1225

There is a growing international recognition that flood risk management in optima forma should be a programmed and flexible process of continuously improving management practices by active learning about the outcome of earlier and ongoing interventions and drivers of change. In the Netherlands, such a long-term, adaptive flood risk management strategy is now being implemented. This so-called second Delta Programme aims to identify and exploit opportunities and capitalize on short-term benefits and opportunistic synergies that arise from change and will require adaptive policymaking. It also requires the financial and institutional means to operate in a long-lasting way, which at the very least, means engaging stakeholders, gathering and disseminating results and adaptation of future plans. Transferring the Dutch approach to other countries is a major challenge that calls for fundamental changes in institutional arrangements at various levels and thus requires customized programmes for strategic institutional change. Recent examples of transfer will provide important lessons of how institutional change can successfully occur and will contribute insights for other countries that attempting to reform their flood risk management strategies. Continuous monitoring and evaluation and sharing international experiences will become crucial for the effective delivery and wider uptake of these new strategies around the globe.  相似文献   

Sulfur and iron speciation in surface sediments along the northwestern margin of the Black Sea   总被引：4，自引：0，他引：4  

Jeroen W. M. Wijsman  Jack J. Middelburg  Peter M. J. Herman  Michael E. Bttcher  Carlo H. R. Heip 《Marine Chemistry》2001,74(4)

The speciation of sedimentary sulfur (pyrite, acid volatile sulfides (AVS), S⁰, H₂S, and sulfate) was analyzed in surface sediments recovered at different water depths from the northwestern margin of the Black Sea. Additionally, dissolved and dithionite-extractable iron were quantified, and the sulfur isotope ratios in pyrite were measured. Sulfur and iron cycling in surface sediments of the northwestern part of the Black Sea is largely influenced by (1) organic matter supply to the sediment, (2) availability of reactive iron compounds and (3) oxygen concentrations in the bottom waters. Biologically active, accumulating sediments just in front of the river deltas were characterized by high AVS contents and a fast depletion of sulfate concentration with depth, most likely due to high sulfate reduction rates (SRR). The δ³⁴S values of pyrite in these sediments were relatively heavy (−8‰ to −21‰ vs. V-CDT). On the central shelf, where benthic mineralization rates are lower, re-oxidation processes may become more important and result in pyrite extremely depleted in δ³⁴S (−39‰ to −46‰ vs. V-CDT). A high variability in δ³⁴S values of pyrite in sediments from the shelf-edge (−6‰ to −46‰ vs. V-CDT) reflects characteristic fluctuations in the oxygen concentrations of bottom waters or varying sediment accumulation rates. During periods of oxic conditions or low sediment accumulation rates, re-oxidation processes became important resulting in low AVS concentrations and light δ³⁴S values. Anoxic conditions in the bottom waters overlying shelf-edge sediments or periods of high accumulation rates are reflected in enhanced AVS contents and heavier sulfur isotope values. The sulfur and iron contents and the light and uniform pyrite isotopic composition (−37‰ to −39‰ vs. V-CDT) of sediments in the permanently anoxic deep sea (1494 m water depth) reflect the formation of pyrite in the upper part of the sulfidic water column and the anoxic surface sediment. The present study demonstrates that pyrite, which is extremely depleted in ³⁴S, can be found in the Black Sea surface sediments that are positioned both above and below the chemocline, despite differences in biogeochemical and microbial controlling factors.  相似文献   

Evaluation of a global ensemble flood prediction system in Peru     

Konstantinos Bischiniotis  Bart van den Hurk  Ervin Zsoter  Erin Coughlan de Perez  Manolis Grillakis  Jeroen C. J. H. Aerts 《水文科学杂志》2013,58(10):1171-1189

ABSTRACT

Flood early warning systems play a more substantial role in risk mitigation than ever before. Hydrological forecasts, which are an essential part of these systems, are used to trigger action against floods around the world. This research presents an evaluation framework, where the skills of the Global Flood Awareness System (GloFAS) are assessed in Peru for the years 2009–2015. Simulated GloFAS discharges are compared against observed ones for 10 river gauges. Forecasts skills are assessed from two perspectives: (i) by calculating verification scores at every river section against simulated discharges and (ii) by comparing the flood signals against reported events. On average, river sections with higher discharges and larger upstream areas perform better. Raw forecasts provide correct flood signals for 82% of the reported floods, but exhibit low verification scores. Post-processing of raw forecasts improves most verification scores, but reduces the percentage of the correctly forecasted reported events to 65%.  相似文献   

XMM–Newton observations of the black hole X-ray transient XTE J1650–500 in quiescence     

Jeroen Homan  Rudy Wijnands  Albert Kong  Jon M. Miller  Sabrina Rossi  Tomaso Belloni  Walter H. G. Lewin 《Monthly notices of the Royal Astronomical Society》2006,366(1):235-237

We report the result of an XMM–Newton observation of the black hole X-ray transient XTE J1650–500 in quiescence. The source was not detected, and we set upper limits on the 0.5–10 keV luminosity of  0.9–1.0 × 10³¹ erg s⁻¹  (for a newly derived distance of 2.6 kpc). These limits are in line with the quiescent luminosities of black hole X-ray binaries with similar orbital periods (∼7–8 h).  相似文献   

Iron-line and continuum flux variations in the RXTE spectra of the black hole candidate XTE J1650−500     

Sabrina Rossi  Jeroen Homan  Jon M. Miller  Tomaso Belloni 《Monthly notices of the Royal Astronomical Society》2005,360(2):763-768

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Submillimeter Studies of Prestellar Cores and Protostars: Probing the Initial Conditions for Protostellar Collapse     

Philippe André  Jeroen Bouwman  Arnaud Belloche  Patrick Hennebelle 《Astrophysics and Space Science》2004,292(1-4):325-337

Improving our understanding of the earliest stages of star formation is crucial to gain insight into the origin of stellar masses, multiple systems, and protoplanetary disks. We discuss recent advances made in this area, thanks to submillimeter mapping observations with large single-dish telescopes and interferometers. Although ambipolar diffusion appears to be too slow cores, there is nevertheless good evidence that the gravitational collapse of isolated protostellar cores is strongly magnetically controlled. We also argue that the beginning of protostellar collapse is much more violent in cluster-forming clouds than in regions of distributed star formation.  相似文献   

Experimental and Numerical Modelling of Flow over Complex Terrain: The Bolund Hill     

Boris Conan  Ashvinkumar Chaudhari  Sandrine Aubrun  Jeroen van Beeck  Jari Hämäläinen  Antti Hellsten 《Boundary-Layer Meteorology》2016,158(2):183-208

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A three-dimensional classification for mathematical pore shape description in complex carbonate reservoir rocks     

Steven Claes  Jeroen Soete  Veerle Cnudde  Rudy Swennen 《Mathematical Geosciences》2016,48(6):619-639

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Lithospheric foundering and underthrusting imaged beneath Tibet     

Min Chen  Fenglin Niu  Jeroen Tromp  Adrian Lenardi  Cin-Ty A. Lee  Wenrong Cao  Julia Ribeiro 《《地质学报》英文版》2018,92(Z1):48-48

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Quantifying seasonal export and retention of nutrients in West European lowland rivers at catchment scale     

Jeroen J. M. de Klein  Albert A. Koelmans 《水文研究》2011,25(13):2102-2111

To set accurate critical values for the protection of lakes and coastal areas, it is crucial to know the seasonal variation of nutrient exports from rivers. This article presents an improved method for estimating export and in‐stream nutrient retention and its seasonal variation. For 13 lowland river catchments in Western Europe, inputs to surface water and exports were calculated on a monthly basis. The catchments varied in size (21 to 486 km²), while annual in‐stream retention ranged from 23 to 84% for N and 39 to 72% for P. A novel calculation method is presented that quantifies monthly exports from lowland rivers based on an annual load to the river system. Inputs in the calculation are annual emission to the surface waters, average monthly river discharge, average monthly water temperature and fraction of surface water area in the catchment. The method accounts for both seasonal variation of emission to the surface water and seasonal in‐stream retention. The agreement between calculated values and calibration data was high (N: r² = 0·93; p < 0·001 and P: r² = 0·81; p < 0·001). Validation of the model also showed good results with model efficiencies for the separate catchments ranging from 31 to 95% (average 76%). This indicates that exports of nitrogen and phosphorus on a monthly basis can be calculated with few input data for a range of West European lowland rivers. Further analysis showed that retention in summer is higher than that in winter, resulting in lower summer nutrient concentrations than that calculated with an average annual input. This implies that accurate evaluation of critical thresholds for eutrophication effects must account for seasonal variation in hydrology and nutrient loading. Our quantification method thus may improve the modelling of eutrophication effects in standing waters. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献