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61.
This paper introduces a generic framework for multi-risk modelling developed in the project ‘Regional RiskScape’ by the Research Organizations GNS Science and the National Institute of Water and Atmospheric Research Ltd. (NIWA) in New Zealand. Our goal was to develop a generic technology for modelling risks from different natural hazards and for various elements at risk. The technical framework is not dependent on the specific nature of the individual hazard nor the vulnerability and the type of the individual assets. Based on this generic framework, a software prototype has been developed, which is capable of ‘plugging in’ various natural hazards and assets without reconfiguring or adapting the generic software framework. To achieve that, we developed a set of standards for treating the fundamental components of a risk model: hazards, assets (elements at risk) and vulnerability models (or fragility functions). Thus, the developed prototype system is able to accommodate any hazard, asset or fragility model, which is provided to the system according to that standard. The software prototype was tested by modelling earthquake, volcanic ashfall, flood, wind, and tsunami risks for several urban centres and small communities in New Zealand.  相似文献   
62.
This article examines visitors’ normative acceptance of encounters with boats at a marine protected area and the extent that the number of boats, size of boats, and size of boat on which individuals were traveling influences these encounter norms. Data were obtained from a survey of 439 people visiting Molokini Shoal Marine Life Conservation District in Hawai’i, and photographs depicting four levels of boat use and three proportions of boat size measured encounter norms. Number of boats most strongly influenced encounter norms, boat size was less influential, and the size of boats on which respondents were traveling had little influence. Visitors wanted fewer boats at this site and a majority would not accept encountering more than 15 or 16 boats at one time. When the impact of boat size was considered, they would not accept encountering more than 12 large boats to 17 small boats. Implications for future research and managing standards of quality and social carrying capacity indicators at this marine protected area are discussed.  相似文献   
63.
Many countries now recognise the need for mitigation of climate change induced by human activities and have incorporated renewable energy resources within their energy policy. There are extensive resources of renewable energy within the marine environment and increasing interest in extracting energy from locations with either large tidal range, rapid flow with and without wave interaction, or large wave resources. However, the ecological implications of altering the hydrodynamics of the marine environment are poorly understood. Ecological data for areas targeted for marine renewable developments are often limited, not least because of the considerable challenges to sampling in high energy environments. In order to predict the scale and nature of ecological implications there is a need for greater understanding of the distribution and extent of the renewable energy resource and in turn, of how marine renewable energy installations (MREIs) may alter energy in the environment. Regional ecological implications of a MREI need to be considered against the greater and global ecological threat of climate change. Finally, it is recommended that the identification of species and biotopes susceptible to the removal of hydrokinetic energy could be a suitable strategy for understanding how a MREI may alter flow conditions.  相似文献   
64.
Rehabilitation of industrial areas: case histories from England and Germany   总被引:4,自引:0,他引:4  
 Contaminated and possibly hazardous ground represents a problem in all of the industrialized countries of the world. The investigation of a site that is suspected of being contaminated differs somewhat from a routine site investigation. Sampling of soils, groundwater and gas-producing material may be required. Various precautions may be necessary in doing this and operatives may have to wear protective clothing. Four case histories have been chosen to illustrate different aspects of the rehabilitation of abandoned contaminated land, namely, investigation, assessment, ground treatment and redevelopment. The first comes from Leeds in West Yorkshire, England, and outlines how a site investigation was undertaken and the nature of the contamination present, together with a note on the suggested redevelopment. The remaining three case histories are taken from the heavily industrialized district of the Ruhr in Germany, where extensive mining of coal and associated industries were developed from the mid-19th century onwards. The first considers the site of the former Graf Moltke mine near Essen. In this instance, the somewhat novel methods of data assessment and ground treatment are dealt with. The Mont Cenis site at Herne-Sodingen is one of the more notable old mining/industrial sites undergoing redevelopment in the state of North Rhine Westphalia. Hence, the case history concentrates of this aspect of rehabilitation. This involves not only the construction of new and interesting structures but an attempt to reduce energy consumption in an attempt to effect the concept of sustainable development of an urban area. The last example deals with the abandoned site of the Minister Achenbach mine at Lünen, where the ground conditions were further complicated by the presence of old bomb craters that had been filled with a variety of materials. In addition, because of the suspected presence of former foundation structures in the ground an electromagnetic survey was carried out across part of the site, the areas of high conductivity suggesting their presence. Received: 15 September 1999 · Accepted: 14 March 2000  相似文献   
65.
We outline how ground-based Fourier transform infrared (FTIR) measurements of stratospheric trace species, obtained with high temporal resolution, could be used to detect filaments of polar vortex air at mid-latitudes and therefore test high spatial resolution chemical transport models (CTMs). Vertical column abundances of HCl, ClONO2, HNO3, N2O and HF have been obtained from FTIR solar absorption measurements made throughout the day from Aberdeen, UK (57°N, 2°W) on several days during winter/spring 1993/94 and 1994/95. The short-timescale ( 2 hours) variability observed in the columns is attributed to real atmospheric variations and is often associated with the passage of high latitude air over Aberdeen. This is confirmed by 3D modelling studies which qualitatively reproduce and rationalise the observed changes in the column data on January 19 1994, January 20 1995 and February 26 1995. We describe the viewing geometry of ground-based FTIR measurements and we suggest a measurement strategy which should maximise the information retrieved on horizontal gradients in stratospheric trace species columns from FTIR measurements.  相似文献   
66.
Landward retreat (marine transgression) is a common response of coastal systems to rising relative sea level. However, given sufficient sediment supply, the coast may advance seaward. The latter response of gravel barriers has been recorded in parts of southeastern and northwestern Canada, where seaward‐rising sets of beach ridges are observed in areas of Holocene RSL rise. Cape Charles Yorke, northern Baffin Island, is a 5 km long gravel foreland characterized by seaward‐rising beach‐ridge crest elevations. The prograded morphology of the Cape Charles Yorke foreland is a prime example of coastal response to a combination of rising RSL and abundant sediment supply, an unusual and little‐documented pattern in the Canadian Arctic. The main gravel supply to Cape Charles Yorke is likely from eroding bedrock and raised marine deposits southwest of the foreland. Although not the dominant sediment source, the Cape Charles Yorke delta contributed to the formation of the foreland by sheltering it from easterly storm waves and providing an anchor point for the prograding ridges. The truncation of relict ridges by the modern shoreline suggests a recent regime shift from continuous deposition to predominant erosion. The cause and timing of this shift are unknown but could result from a recent dwindling in sediment supply, increased accommodation space, increased wave energy, and/or an accelerated rise of relative sea level.  相似文献   
67.
Tidal currents derived from current meter measurements are compared with the output from a barotropic tidal model of the New Zealand region. For the semi‐diurnal constituents there was very good agreement for the M2 tide and good agreement for the S2 tide. For the diurnal constituents (Kl, Ol) it was found that as the amplitude of the constituents decreased so did both the model/observation agreement and the accuracy of the observed tidal ellipse parameters. Consequently it was not possible to decide whether differences arose through shortcomings in the model or in the data. However, the overall performance of the model as a prognostic tool for ocean tidal current simulation appears to be good.  相似文献   
68.
It is argued that mylonite zones result from translatory movements between rock masses and that the deformation mechanism is one of simple shear. Evidence is adduced to show that the mylonite zones in the Moine Thrust Belt of northwestern Scotland were developed in association with the inverted limbs of early Caledonian folds which trend parallel to the thrust front. On this basis a method is developed for the determination of shear strain from parameters which can be measured in mylonites which contain deformed Skolithos worm burrows. Very large strains are indicated (γ - 10). Some general implications are discussed.  相似文献   
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