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The economics of climate change impacts and policy benefits at city scale: a conceptual framework 总被引：2，自引：0，他引：2
Cities are particularly vulnerable to climate change and climate extremes in part because they concentrate many activities,
people and wealth in limited areas. As a result they represent an important scale for assessment and understanding of climate
change impacts. This paper provides a conceptual and methodological framework for urban economic impact assessment of climate
change. The focus of the paper is on model-based analysis of future scenarios, including a framing of uncertainty for these
projections, as one valuable input into the decision-making process. The paper highlights the main assessment difficulties,
methods and tools, and selected examples across these areas. A number of challenges are unique to climate change impact assessment
and others are unique to the problem of working at local scales. The paper also identifies the need for additional research,
including the need for more integrated and systemic approaches to address climate change as a part of the urban development
challenge as well as the need to assess the economic impacts of climate change and response policy at local scale. 相似文献
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Fabrice Ardhuin François-Régis Martin-Lauzer Bertrand Chapron Philippe Craneguy Fanny Girard-Ardhuin Tanos Elfouhaily 《Comptes Rendus Geoscience》2004,336(12):1121-1130
We model the drift velocity near the ocean surface separating the motion induced by the local current, itself influenced by winds and waves, and the motion induced by the waves, which are generated by local and remote winds. Application to the drift of ‘tar balls’, following the sinking of the oil tanker Prestige-Nassau in November 2002, shows that waves contribute at least one third of the drift for pollutants floating 1 m below the surface, with a mean direction about 30° to the right of the wind-sea direction. Although not new, this result was previously obtained with specific models, whereas the formalism used here combines classical wave and circulation forecasting models. To cite this article: F. Ardhuin et al., C. R. Geoscience 336 (2004). 相似文献
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Monitoring gravel augmentation in a large regulated river and implications for process‐based restoration 
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下载免费PDF全文 Fanny Arnaud Hervé Piégay David Béal Pierre Collery Lise Vaudor Anne‐Julia Rollet 《地球表面变化过程与地形》2017,42(13):2147-2166
The artificial gravel augmentation of river channels is increasingly being used to mitigate the adverse effects of river regulation and sediment starvation. A systematic framework for designing and assessing such gravel augmentations is still lacking, notably on large rivers. Monitoring is required to quantify the movement of augmented gravel, measure bedform changes, assess potential habitat enhancement, and reduce the uncertainty in sediment management. Here we present the results of an experiment conducted in the Rhine River (French and German border). In 2010, 23 000 m3 of sediments (approximately the mean annual bedload transport capacity) were supplied in a by‐passed reach downstream of the Kembs dam to test the feasibility of enhancing sediment transport and bedform changes. A 620‐m‐long and 12‐m‐wide gravel deposit was created 8 km downstream from the dam. Monitoring included topo‐bathymetric surveys, radio‐frequency particle tracking using passive integrated transponder (PIT) tags, bed grain size measurement, and airborne imagery. Six surveys performed since 2009 have been described (before and after gravel augmentation, and after Q2 and Q15 floods). The key findings are that (i) the augmented gravel was partially dispersed by the first flood event of December 2010 (Q1); (ii) PIT tags were found up to 3200 m downstream of the gravel augmentation site after four years, but the effects of gravel augmentation could not be clearly distinguished from the effects of floods and internal remobilization on more than 3500 m downstream; (iii) linear and log‐linear relationships linking bedload transport, particle mobility, and grain size were established; and (iv) combined bathymetry and PIT tag surveys were useful for evaluating potential environmental risks and the first morpho‐ecological responses. This confirmed the complementary nature of such techniques in the monitoring of gravel augmentation in large rivers. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
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Fanny Girard-Ardhuin B. Bénech B. Campistron J. Dessens S. Jacoby-Koaly 《Boundary-Layer Meteorology》2003,106(1):93-115
On 11 August 1999, a near-total solar eclipse (80%) was observed in Campistrous, France. The influence of this particular event on the atmospheric boundary layer was observed with a UHF-RASS radar, a sodar and an instrumented mast. The changes in turbulence intensity, radar reflectivity, and temperature on the radiative budget are described in relation to collocated ground meteorological data. The impact of the eclipse induces a clear response of the atmosphere, with a time lag of 15 to 30 min, perceptible in several mean and turbulent meteorological variables up to the top of the atmospheric boundary layer. 相似文献
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Insights into the origin of primitive silica-undersaturated arc magmas of Aoba volcano (Vanuatu arc) 总被引：1，自引：1，他引：0
Fanny Sorbadere Pierre Schiano Nicole Métrich Esline Garaebiti 《Contributions to Mineralogy and Petrology》2011,162(5):995-1009
Aoba picrites in Vanuatu arc (Southwestern Pacific) offer the opportunity to address the question of the origin of Si-undersaturated
arc magmas, through the geochemical study of their olivine-hosted melt inclusions. These latter delineate a differentiation
trend of calc-alkaline silica-undersaturated basalts, with typical trace-element patterns of arc magmas. The most primitive
melt inclusions, preserved in olivines with Fo ≥ 89, have normative nepheline compositions with CaO/Al2O3 > 0.8, but belong to three distinct populations differing in their enrichment or depletion in LILE, Cl, and alkalis (Rb,
K). The dominant population is characterized by medium-LILE concentrations (La/Yb ~ 7–8) and represents the parental magma
of the Aoba lavas. The two others (La/Yb ~ 20 and 2) are either significantly enriched or extremely depleted in LILE, Cl,
and alkalis. This compositional variability of primitive magma batches requires the multi-stage mixing between melts generated
by partial melting of both peridotite and clinopyroxene-rich lithologies. Medium-LILE magma derives from the mixing between
peridotite- and clinopyroxenite-derived melts, whereas the high- and low-LILE melts involve amphibole-bearing and amphibole-free
clinopyroxenite sources, respectively. 相似文献
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Fanny Cattani Barbara A. Cohen Cameron M. Mercer Agnes J. Dahl 《Meteoritics & planetary science》2023,58(4):591-611
Several laboratories have been investigating the feasibility of in situ K-Ar dating for use in future landing planetary missions. One drawback of these laboratory demonstrations is the insufficient analogy of the analyzed analog samples with expected future targets. We present the results obtained using the K-Ar laser experiment (KArLE) on two old and K-poor chondritic samples, Pułtusk and Hvittis, as better lunar analogs. The KArLE instrument uses laser ablation to vaporize rock samples and quantifies K content by laser-induced breakdown spectroscopy (LIBS), Ar by quadrupole mass spectrometry (QMS), and ablated mass by laser profilometry. We performed 64 laser ablations on the chondrites to measure spots with a range of K2O and Ar content and used the data to construct isochrons to determine the chondrite formation age. The KArLE isochron ages on Pułtusk and Hvittis are 5059 ± 892 Ma and 4721 ± 793 Ma, respectively, which is within the uncertainty of published reference ages, and interpreted as the age of their formation. The uncertainty (2σ) on the KArLE ages obtained in this study is better than 20% (18% for Pułtusk and 17% for Hvittis). The precision, which compares our obtained ages to the reference ages, is also better than 20% (11% for Pułtusk and 4% for Hvittis). These results are encouraging for understanding the limits of this technique to measure ancient planetary samples and for guiding future improvements to the instrument. 相似文献
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Fanny Chenillat Peter J. S. Franks Xavier Capet Pascal Rivière Nicolas Grima Bruno Blanke Vincent Combes 《Ocean Dynamics》2018,68(7):761-777
The California Current System (CCS) is an eastern boundary upwelling system characterized by strong eddies that are often generated at the coast. These eddies contribute to intense, long-distance cross-shelf transport of upwelled water with enhanced biological activity. However, the mechanisms of formation of such coastal eddies, and more importantly their capacity to trap and transport tracers, are poorly understood. Their unpredictability and strong dynamics leave us with an incomplete picture of the physical and biological processes at work, their effects on coastal export, lateral water exchange among eddies and their surrounding waters, and how long and how far these eddies remain coherent structures. Focusing our analysis on the southern part of the CCS, we find a predominance of cyclonic eddies, with a 25-km radius and a SSH amplitude of 6 cm. They are formed near shore and travel slightly northwest offshore for ~?190 days at ~?2 km day?1. We then study one particular, representative cyclonic eddy using a combined Lagrangian and Eulerian numerical approach to characterize its kinematics. Formed near shore, this eddy trapped a core made up of ~?67% California Current waters and ~?33% California Undercurrent waters. This core was surrounded by other waters while the eddy detached from the coast, leaving the oldest waters at the eddy’s core and the younger waters toward the edge. The eddy traveled several months as a coherent structure, with only limited lateral exchange within the eddy. 相似文献