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991.
This paper investigates whether an inefficient allocation of abatement due to constraints on the use of currently available low carbon mitigation options can promote innovation in new technologies and have a positive impact on welfare. We focus on the case of a nuclear power phase-out and endogenous technical change in energy efficiency and alternative low carbon technologies. The research is inspired by the re-thinking about nuclear power deployment which took place in some countries, especially in Western Europe, after the Fukushima accident in March 2011. The analysis uses an Integrated Assessment Model, WITCH, which features multiple externalities related to greenhouse gas emissions and innovation market failures. Our results show that phasing out nuclear power stimulates R&D investments and deployment of technologies with large learning potential. The resulting technology benefits that would not otherwise occur due to intertemporal and international externalities almost completely offset the economic costs of foregoing nuclear power. The extent of technology benefits depends on the stringency of the climate policy and is distributed unevenly across countries. 相似文献
992.
Andrea De Montis Simone Caschili Alessandro Chessa 《Journal of Geographical Systems》2011,13(1):49-65
The aim of this paper is to study the dynamics of the commuting system of two insular regions of Italy, Sardinia and Sicily,
inspected as complex networks. The authors refer to a 20-year time period and take into account three census data sets about
the work and study-driven inter-municipal origin-destination movements of residential inhabitants in 1981, 1991 and 2001.
Since it is likely that the number of municipalities (in this case, the vertices of the system) does not display sharp variations,
the authors direct the study to the variation of the properties emerging through both a topological and a weighted network
representation of commuting in the time periods indicated. 相似文献
993.
Ferdinando De Tomasi M. Marcello Miglietta M. Rita Perrone 《Boundary-Layer Meteorology》2011,139(3):521-541
A lidar system is used to determine the diurnal evolution of the planetary boundary layer (PBL) height on a summer day characterized
by anticyclonic conditions. The site is located some 15 km distant from the sea, on a peninsula in south-east Italy. Contrary
to expectations, the PBL height, after an initial growth consequent to sunrise, ceases to increase about 2 h before noon and
then decreases and stabilizes in the afternoon. An interpretation of such anomalous behaviour is provided in terms of trajectories
of air parcels towards the lidar site, which are influenced by the sea breeze, leading to a transition from a continental
boundary layer to a coastal internal boundary layer. The results are analyzed using mesoscale numerical model simulations
and a simple model that allows for a more direct interpretation of experimental results. 相似文献
994.
The study used a modelling approach to assess the potential impacts of likely climate change and increase in CO2 concentration on the wheat growth and water balance in Murray?CDarling Basin in Australia. Impacts of individual changes in temperature, rainfall or CO2 concentration as, well as the 2050 and 2070 climate change scenarios, were analysed. Along an E?CW transect, wheat yield at western sites (warmer and drier) was simulated to be more sensitive to temperature increase than that at eastern sites; along the S?CN transect, wheat yield at northern warmer sites was simulated to be more sensitive to temperature increase, within 1?C3°C temperature increase. Along the E?CW and S?CN transects, wheat at drier sites would benefit more from elevated [CO2] than at wetter sites, but more sensitive to the decline in rainfall. The increase in temperature only did not have much impact on water balance. Elevated [CO2] increased the drainage in all the sites, whilst rainfall reduction decreased evapotranspiration, runoff and drainage, especially at drier sites. In 2050, wheat yield would increase by 1?C10% under all climate change scenarios along the S?CN transect, except for the northernmost site (Dalby). Along the E?CW transect, the most obvious increase of wheat yields under all climate change scenarios occurred in cooler and wetter eastern sites (Yass and Young), with an average increase rate of 7%. The biggest loss occurred at the driest sites (Griffith and Swan Hill) under A1FI and B2 scenarios, ranging from ?5% to ?16%. In 2070, there would be an increased risk of yield loss in general, except for the cool and wet sites. Water use efficiency was simulated to increase at most of the study sites under all the climate change scenarios, except for the driest site. Yield variability would increase at drier sites (Ardlethan, Griffith and Swan Hill). Soil types would also impact on the response of wheat yield and water balance to future climate change. 相似文献
995.
996.
Ambient noise measurements have been performed at local and small scales in the Neapolitan and surrounding areas (Campania, southern Italy) by employing two broad-band Kinemetrics Q330 stations, equipped with Episensor ES-T three component accelerometers. In both experiments frequency time analysis (FTAN method) has been performed on the vertical and radial components of noise cross correlations to retrieve the Rayleigh wave dispersion (Green??s function). At local scale, over an interstation distance of about 26?km, the group velocity dispersion values have been compared with those obtained from FTAN analysis on recordings of two earthquakes with similar path. At small scale, measurements have been carried out over an interstation distance of about 440?m in the public gardens of Scampia, the northernmost quarter of Naples. The Rayleigh wave group velocity dispersion data obtained from noise cross correlation, have been combined with those from active seismic experiment along the same alignment, but shorter (120?m offset). The non linear inversion of such a dispersion curve has allowed the definition of V S models to depths of 100?m, in agreement with nearby stratigraphy. Moreover, a good agreement has resulted for the resonance frequency among the H/V ratio, the ellipticity of the fundamental mode computed for the chosen V S model, and the average two-dimensional (2D) spectral amplification computed along a cross section representative of the Scampia quarter. 相似文献
997.
Based on the relationship between the geological structures and river patterns, the preliminary prediction of the karstic features in the Kuala Lumpur Limestone Formation, based on the existing geological, map appears to be directed between N030° to 070° and N120° to 150°. The factual evidence of this occurrence is obtained from investigation in the field: first, using the two sites exposed for construction of the SMART tunnel under Kuala Lumpur and second, based on the SMART tunnel project rock cores recovery. A much detailed prediction was made by re-evaluating the TCR, RQD and SCR values. The reassessment of these values enables the drilled ground to be classified into four different qualities of rock mass: good quality limestone; moderate quality limestone; weathered limestone; and fully developed void-like karst. According to this new classification system, the tunnel appears to align generally in the heavily karstified limestone in the northern section and massive good quality limestone in the southern section of the study area; which is represented as rose diagrams. The evidence for this analysis is given and the methods used for these studies are explained. 相似文献
998.
In this paper we show the seismicity and velocity structure of a segment of the Alpine retro-belt front along the continental collision margin of the Venetian Alps (NE Italy). Our goal is to gain insight on the buried structures and deep fault geometry in a “silent” area, i.e., an area with poor instrumental seismicity but high potential for future earthquakes, as indicated by historical earthquakes (1695 Me = 6.7 Asolo and 1936 Ms = 5.8 Bosco del Cansiglio). Local earthquakes recorded by a dense temporary seismic network are used to compute 3-D Vp and Vp/Vs tomographic images, yielding well resolved images of the upper crust underneath the south-Alpine front. We show the presence of two main distinct high Vp S-verging thrust units, the innermost coincides with the piedmont hill and the outermost is buried under a thick pile of sediments in the Po plain.Background seismicity and Vp/Vs anomalies, interpreted as cracked fluid-filled volumes, suggest that the NE portion of the outermost blind thrust and its oblique/lateral ramps may be a zone of high fluid pressure prone to future earthquakes.Three-dimensional focal mechanisms show compressive and transpressive solutions, in agreement with the tectonic setting, stress field maps and geodetic observations. The bulk of the microseismicity is clustered in two different areas, both in correspondence of inherited lateral ramps of the thrust system. Tomographic images highlight the influence of the paleogeographic setting in the tectonic style and seismic activity of the region. 相似文献
999.
The debate on genetic modification (GM) is persistent, polarized and mainly involves organized groups at the national level. With the European Union’s new policy of coexistence, commercial cultivation of GM crops is expected by the Dutch Ministry of Agriculture, Nature and Food Quality within the next few years, especially maize (BT) and potato (Phytophthera resistance and starch production). This makes the debate relevant for those directly confronted with this cultivation: the inhabitants of local rural communities. In The Netherlands, stakeholders formulated coexistence rules to prevent problems between conventional, organic and GM farmers that grow their crops in the same limited land area. Little is known, however, regarding the perceptions of the non-farming inhabitants of rural communities (“the neighbours”) in the debate. This paper presents the results of a focus group-based argumentative analysis of whether (and how) the GM issues play a decisive role among non-farming inhabitants of four rural communities in the Netherlands. We analysed the arguments in relation to a conceptual model that describes the potential rise and dynamics from a pre-Nimby ambivalence towards an outspoken Nimby position. We observed that the GM debate was given very little priority relative to other national issues on the political agenda and that more social cohesion correlates with fewer arguments in the national debate. It is argued that this mechanism keeps the Nimby ambivalence in an undetermined mode, which in turn diminishes the chances of radical rural-based protest against local GM cultivation of crops. 相似文献
1000.
Christian Kuhlicke Anna Scolobig Sue Tapsell Annett Steinführer Bruna De Marchi 《Natural Hazards》2011,58(2):789-810
Social vulnerability is a term that has been widely used in the natural hazards literature for quite a few years now. Yet, regardless of how scholars
define the term, the approaches and indicators they use remain contested. This article presents findings from social vulnerability
assessments conducted in different case studies of flood events in Europe (Germany, Italy and the UK). The case studies relied
upon a common set of comparable indicators, but they also adopted a context-sensitive, qualitative approach. A shared finding
across the case studies was that it was not possible to identify a common set of socio-economic–demographic indicators to
explain social vulnerability of groups and/or individuals for all phases of the disastrous events. Similarly, network-related
indicators as well as location- and event-specific indicators did not have the relevance we expected them to have. The results
underline that vulnerability is a product of specific spatial, socio-economic–demographic, cultural and institutional contexts
imposing not only specific challenges to cross-country research concerning social vulnerability to flooding but also to attempts
at assessing social vulnerability in general. The study ends with some reflections upon the methodological, practical and
theoretical implications of our findings. 相似文献