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641.
A spatially explicit scenario-driven model of adaptive capacity to global change in Europe 总被引:1,自引:0,他引:1
Lilibeth Acosta Richard J.T. Klein Pytrik Reidsma Marc J. Metzger Mark D.A. Rounsevell Rik Leemans Dagmar Schröter 《Global Environmental Change》2013,23(5):1211-1224
Traditional impact models combine exposure in the form of scenarios and sensitivity in the form of parameters, providing potential impacts of global change as model outputs. However, adaptive capacity is rarely addressed in these models. This paper presents the first spatially explicit scenario-driven model of adaptive capacity, which can be combined with impact models to support quantitative vulnerability assessment. The adaptive capacity model is based on twelve socio-economic indicators, each of which is projected into the future using four global environmental change scenarios, and then aggregated into an adaptive capacity index in a stepwise approach using fuzzy set theory. The adaptive capacity model provides insight into broad patterns of adaptive capacity across Europe, the relative importance of the various determinants of adaptive capacity, and how adaptive capacity changes over time under different social and economic assumptions. As such it provides a context for the implementation of specific adaptation measures. This could improve integrated assessment models and could be extended to other regions. However, there is a clear need for a better theoretical understanding of the adaptive capacity concept, and its relationship to the actual implementation of adaptation measures. This requires more empirical research and coordinated meta-analyses across regions and economic sectors, and the development of bottom-up modelling techniques that can incorporate human decision making. 相似文献
642.
Marc Blanchard Etienne Balan Paola Giura Keevin Béneut Haohao Yi Guillaume Morin Carlos Pinilla Michele Lazzeri Andrea Floris 《Physics and Chemistry of Minerals》2014,41(4):289-302
The infrared spectrum and its temperature dependence (20–320 K) were collected on a synthetic goethite sample (α-FeOOH). In addition, the infrared powder absorption spectrum of goethite and aluminum-substituted goethite was computed using ab initio quantum mechanical calculations based on density functional theory. This combined experimental and theoretical approach allows (1) the unequivocal assignment of absorption bands to the corresponding vibrational modes, (2) separate identification of the effects of the particle shape and of the aluminum substitution on the infrared spectrum, and (3) a discussion of the anharmonic properties and the origin of the line broadening in goethite. In particular, the two well-resolved OH bending absorption bands show different temperature evolution. Their detailed analysis suggests that the broadening of the band at ~800 cm?1 cannot be described solely by a usual three-phonon process. The strong anharmonic behavior of this mode implies the addition of a four-phonon process, such as a pure dephasing process. In our calculations, the effect of the Hubbard U correction is also investigated and found to be most visible on the OH stretching and bending modes, in relation to the associated structural relaxation. The OH stretching frequencies decrease, leading to a better agreement with experimental frequencies, while the OH bending frequencies increase. 相似文献
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644.
Muriel Gargaud Francis Albarède Laurent Boiteau Marc Chaussidon Emmanuel Douzery Thierry Montmerle 《Earth, Moon, and Planets》2006,98(1-4):11-38
This chapter concerns the tools with which time or durations are measured in the various disciplines contributing to the chronology of the solar system until the emergence of life. These disciplines and their tools are successively: astronomy (use of the Herzsprung–Russell diagram), geochemistry (radioactive dating), chemistry (no clocks!), and biology (molecular clocks, based on rates of molecular evolution over phylogenetic trees). A final section puts these tools in perspective, showing the impossibility of using a unique clock to describe the evolution of the solar system and of life until today. 相似文献
645.
The DEEP2 Galaxy Redshift Survey: the relationship between galaxy properties and environment at z∼ 1
Michael C. Cooper Jeffrey A. Newman † Darren J. Croton Benjamin J. Weiner Christopher N. A. Willmer Brian F. Gerke Darren S. Madgwick † S. M. Faber Marc Davis Alison L. Coil † Douglas P. Finkbeiner Puragra Guhathakurta David C. Koo 《Monthly notices of the Royal Astronomical Society》2006,370(1):198-212
646.
Marc S. Seigar Paul D. Lynam Nicole E. Chorney 《Monthly notices of the Royal Astronomical Society》2003,344(1):110-114
We present a ground-based, near-infrared, K -band image and a Hubble Space Telescope ( HST ) WFPC2 image of the brightest cluster galaxy in Abell 193 (IC 1695). This object was selected as the central cluster galaxy using X-ray information. Both images reveal a triple nucleus structure. Previously, this galaxy was thought to have only two nuclei. We present colours and magnitudes and a colour plot of the three nuclei. The nuclear structure and colours of the nuclei in this galaxy suggest that a merger may have taken place in its recent history. 相似文献
647.
Jitsangiam Peerapong Pra-ai Suriyavut Boulon Marc Jenck Orianne Chen Xiaobin Techavorasinsakul Supot 《Acta Geotechnica》2022,17(5):1829-1845
Acta Geotechnica - This paper aims to investigate the effects of cyclic shear amplitudes and loading sequences on a soil–structure interface using direct shear tests under a large number of... 相似文献
648.
Bangladesh is a country that comprises much of the world’s largest delta, formed from the Ganges, Brahmaputra, and Meghna (GBM) rivers and their tributaries. Flooding is a fact of life in Bangladesh where up to two-thirds of the country is flooded annually from combined monsoonal rains and Himalayan snowmelt. For this reason, understanding flood dynamics on both local and regional scales is critical. However, flood hazard studies to date typically rely on single flooding events to create flood maps and to evaluate flood hazards using satellite imagery. Here we use geographic information systems to analyze weekly water level data from 304 river gauges and over 1200 groundwater gauges from the Bangladesh Water Development Board to determine the spatial and temporal changes in flood depth and extent. These data cover an eight year period from 2002 to 2010 and provide a temporal resolution that match or are better than that of available satellite imagery. Country-wide ground and surface water levels and corresponding annual flooding events were determined along with groundwater level, flooding, and precipitation trends in Bangladesh at multiple scales. We find that while precipitation within the GBM basin has steadily increased through the time series, the average country-wide inundation depth and absolute water level has been decreasing. These respective trends could be attributed to improved flood management strategies in Bangladesh and surrounding countries that are within the GBM basin, as well as fluctuating weather patterns, declining volume of Himalayan snowmelt runoff, dam construction upriver from the GBD both within and outside the Bangladesh border, and increased groundwater abstraction of shallow groundwater aquifers for sustaining life in the eighth most populous country in the world. 相似文献
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650.
Voltammetric Determination of High Field‐Strength Elements (Ti,Zr, Hf,Nb, Ta) in Geological Matrices 下载免费PDF全文
A voltammetric method for the determination of the high field‐strength elements Ti, Zr, Hf, Nb and Ta by adsorptive stripping of their tartrate complexes is presented. The applicability of the method to geological and metallurgical samples is illustrated by the analysis of certified reference materials (USGS BCR‐2 basalt, BCS‐CRM 388 zircon and Euronorm CRM 579‐1 ferroniobium). Suitable sample preparation techniques, involving fusion with LiBO2 and acidic and basic fluxes, followed by preliminary separation by anion chromatography are described. The method is rapid, affordable and environmentally friendly as it does not require problematic compounds such as hydrofluoric acid or toxic solvents and represents an alternative to more commonly used methods (AAS, ICP‐OES, ICP‐MS). 相似文献