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151.
Sabine L. Perch-Nielsen 《Climatic change》2010,100(3-4):579-606
The attractiveness of a region for touristic activities depends strongly on the local weather and climate. This paper analyses the vulnerability of the beach tourism sector towards climate change by means of an index approach on a country level. A vulnerability framework for the tourism sector is developed and on its basis, indicators are defined for exposure, sensitivity and adaptive capacity. A transparent index approach, including a robustness analysis with multiple transformation methods and weighting sets, yields an assessment of the overall relative vulnerability of the beach tourism sector in 51 countries. Aggregate results on an annual level are presented as a starting point for a more detailed comparison of countries based on the individual indicators. The important limitations regarding the availability of accurate indicators as well as the concept of vulnerability itself are discussed. Despite these limitations, the present study contributes to integrating the numerous direct as well as indirect effects climate change may have on beach tourism. 相似文献
152.
The Galactic open cluster Westerlund 1 (Wd 1) represents the ideal local template for extragalactic young massive star clusters, because it is currently the only nearby young cluster with a mass of ~105?M⊙. Its proximity makes spatially resolved studies of its stellar population feasible, and additionally permits direct comparison of its properties with measurements of velocity dispersion and dynamical mass for spatially unresolved extragalactic clusters. Recently, we published the dynamical mass estimate based on spectra of four red supergiants. We have now identified six additional stars which allow a determination of radial velocity from the wavelength covered in our VLT/ISAAC near-infrared spectra (CO bandhead region near 2.29 μm), significantly improving statistics. Using a combination of stepping and scanning the slit across the cluster center, we covered an area which included the following suitable spectral types: four red supergiants, five yellow hypergiants, and one B-type emission-line star. Our measured velocity dispersion is 9.2 km?s?1. Together with the cluster size of 0.86 pc, derived from archival near-infrared SOFI-NTT images, this yields a dynamical mass of 1.5×105 M⊙. Comparing this to the mass derived via photometry, there is no indication that the cluster is currently undergoing dissolution. 相似文献
153.
A multicriteria approach for flood risk mapping exemplified at the Mulde river,Germany 总被引:6,自引:4,他引:2
In this paper we develop a GIS-based multicriteria flood risk assessment and mapping approach. This approach includes flood
risks which are not measured in monetary terms; it shows the spatial distribution of multiple risks, and it is able to deal
with uncertainties in criteria values and to show their influence on the overall flood risk assessment. Additionally, the
approach can be used to show the spatial allocation of the flood effects if risk reduction measures are implemented. The approach
is applied to a pilot study for the River Mulde in Saxony, Germany, heavily affected by the hazardous flood in 2002. Therefore,
a GIS database of economic, social and environmental risk criteria was created. Two different multicriteria decision rules,
a disjunctive and an additive weighting approach, are utilised for an overall flood risk assessment in the area. For implementation,
a software tool (FloodCalc) was developed supporting both, the risk calculation of the single criteria as well as the multicriteria
analysis.
相似文献
Volker MeyerEmail: |
154.
Hani Serhal Daniel Bernard Jamal El Khattabi Bastin-Lacherez Sabine Isam Shahrour 《Environmental Geology》2009,57(7):1579-1592
Since 1975, Europe sets up its policy to limit the degradation and the pollution of the aquatic environments through 30 directives
and regulations. In the north of France, the nitrate concentrations measured in the groundwater exceed the water drinking
limit fixed at 50 mg/L by the European framework directive in the field of water (2000/60/EC). This high concentration is
due to intensive agriculture, industrialization and demographic growth. Several programs were launched in order to resolve
this situation: “Ferti-better” or the use of fertilizer in moderation and installation and amelioration of wastewater collect
and treatment systems. In order to estimate the influence of the anthropic activities on the quality of groundwater in the
“Artois-Picardy” basin, a preliminary validation on parcel and district scale were necessary. The impact of these programs
in the “Cambrai district” was evaluated using an integrated approach, which is based on the use of four numerical models:
AgriFlux, VS2DT, Modflow and MT3D. The results illustrate an improvement due to the “Ferti-Better” program initiated in 1990
and punctual degradation under urbanized areas. Predictions (2015) show a spatial evolution of nitrates concentration varying
with the thickness of unsaturated layer. The integrated model constitutes an efficient tool for predicting the evolution of
the groundwater quality. This approach is important to control the application of the new European laws in the water field. 相似文献
155.
Biogeochemical controls on authigenic carbonate formation at the Chapopote “asphalt volcano”, Bay of Campeche 总被引:1,自引:0,他引:1
Thomas H. Naehr Daniel Birgel Gerhard Bohrmann Ian R. MacDonald Sabine Kasten 《Chemical Geology》2009,266(3-4):399-411
The Campeche Knolls in the Bay of Campeche, southern Gulf of Mexico, were investigated through detailed seafloor mapping, ROV surveys, and sediment and pore water sampling. The knolls are elongated, submarine hills created by salt tectonics with a positive relief of up to 800 m above the surrounding seafloor. Several of the knolls are associated with sea-surface oil slicks identified from satellite data, indicating the presence of hydrocarbon seeps on the seafloor. One of the knolls, named “Chapopote”, was studied in detail during two international research expeditions (SO174/2 and M67/2) and is characterized by extensive hydrocarbon seepage including large asphalt flows, oil and gas seeps, and seafloor gas hydrate deposits. Chemosymbiotic biological communities and authigenic carbonate deposits are associated with the seeps and are the result of both biogeochemical turnover and the interaction between downward-diffusing seawater and hydrocarbon-rich pore fluids at shallow sediment depth. Authigenic carbonates are characterized by aragonite, exhibit a porous texture, and are cemented by a matrix of microsparitic to sparitic aragonite. Macropores of the carbonates were completely filled with liquid oil. Carbonate microfabrics include peloidal or clotted fabrics that may indicate the existence of microenvironments resulting from microbial metabolism. Banded/botryoidal aragonite cements line the intra- and bioclasts and incompletely fill the pore spaces. The stable carbon isotopic composition of authigenic aragonite varies between − 28.6‰ and − 17.9‰ (PDB), identifying oil oxidation as the primary source of carbon to the DIC pool, while lipid biomarker data demonstrate the concurrent existence of microbial communities responsible for anaerobic oxidation of methane (AOM). These observations indicate the presence of additional, AOM-independent reactions responsible for carbon sequestration at hydrocarbon seeps and demonstrate the complexity of biogeochemical processes at seep sites in the Gulf of Mexico basin. Oxygen isotope data of authigenic aragonite vary from + 2.5‰ to + 3.8‰ (PDB), indicating carbonate precipitation in slight disequilibrium with the surrounding pore fluids. 相似文献
156.
157.
GPS/INS navigation precision and its effect on airborne radio occultation retrieval accuracy 总被引:1,自引:1,他引:0
Paytsar Muradyan Jennifer S. Haase Feiqin Xie James L. Garrison Justin Voo 《GPS Solutions》2011,15(3):207-218
An airborne radio occultation (RO) system has been developed to retrieve atmospheric profiles of refractivity, moisture, and temperature. The long-term objective of such a system is deployment on commercial aircraft to increase the quantity of moisture observations in flight corridors in order to improve weather forecast accuracy. However, there are several factors important to operational feasibility that have an impact on the accuracy of the airborne RO results. We investigate the effects of different types of navigation system noise on the precision of the retrieved atmospheric profiles using recordings from the GNSS Instrument System for Multistatic and Occultation Sensing (GISMOS) test flights, which used an Applanix POS/AV 510 Global Positioning System (GPS)/Inertial Navigation System (INS). The data were processed using a carrier phase differential GPS technique, and then the GPS position and inertial measurement unit data were combined in a loosely coupled integrated inertial navigation solution. This study quantifies the velocity precision as a function of distance from GPS reference network sites, the velocity precision with or without an inertial measurement unit, the impact of the quality of the inertial measurement unit, and the compromise in precision resulting from the use of real-time autonomous GPS positioning. We find that using reference stations with baseline lengths of up to 760?km from the survey area has a negligible impact on the retrieved refractivity precision. We also find that only a small bias (less than 0.5% in refractivity) results from the use of an autonomous GPS solution rather than a post-processed differential solution when used in an integrated GPS/INS system. This greatly expands the potential range of an operational airborne radio occultation system, particularly over the oceans, where observations are sparse. 相似文献
158.
The microstructural evolution of polymineralic contact metamorphic calcite marbles (Adamello contact aureole) with variable volume fractions of second-phase minerals were quantitatively analyzed in terms of changes in grain size and nearest neighbor relations, as well as the volume fractions, dispersion and occurrences of the second phases as a function of changing metamorphic conditions. In all samples, the calcite grain size is controlled by pinning of grain boundaries by second phases, which can be expressed by the Zener parameter (Z), i.e., the ratio between size and volume fraction of the second phases. With increasing peak metamorphic temperature, both the sizes of matrix grains and second phases increase in dependence on the second-phase volume fraction. Two distinct coarsening trends are revealed: trend I with coupled grain coarsening limited by the growth of the second phases is either characterized by large-sized or a large number of closely spaced-second phase particles, and results finally in a dramatic increase in the calcite grain size with Z. Trend II is manifest by matrix controlled grain growth, which is retarded by the presence of single second-phase particles that are located on calcite grain boundaries. It is supported by grain boundary pinning induced by triple junctions, and the calcite grain size increases moderately with Z. The two different grain coarsening trends manifest the transition between relatively pure polymineralic aggregates (trend II) and microstructures with considerable second-phase volume fractions of up to 0.5. The variations might be of general validity for any polymineralic rock, which undergoes grain coarsening during metamorphism. The new findings are important for a better understanding of the initiation of strain localization based on the activation of grain size dependent deformation mechanisms. 相似文献
159.
160.
In this paper, we present an approach to modelling multicriteria flood vulnerability which integrates the economic, social
and ecological dimension of risk and coping capacity. We start with an existing multicriteria risk mapping approach. The term
risk is used here in a way that could be called a starting point view, looking at vulnerability without considering coping capacities. We extend this approach by a multicriteria modelling of coping capacities towards an end point view of vulnerability. In doing so, we explore a way to differentiate coping capacity from flood risk in each of the dimensions
of vulnerability. The approach is tested in an urban case study, the city of Leipzig, Germany. Our results show that it is
possible to map multicriteria risks as well as coping capacities and relate them in a simple way. However, a detailed calculation
of end point vulnerability would require more detailed knowledge on the causal relationships between risk and coping capacity criteria
and their relative importance. 相似文献