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11.
A method is introduced for issuing tsunami warnings in the Australian region based on numerical model output. The method considers
the maximum modelled wave amplitude within pre-defined coastal waters zones and uses this as a proxy for the potential impact
on the coast. A three-level stratified warning is proposed: (1) No threat, (2) Marine threat and (3) Land threat. This method
is applied to several case studies and the resulting warning characteristics are shown. While the method has its limitations,
it is a significant improvement over current operational warning strategies, which are typically based solely on the magnitude
of the earthquake and distance from the source. 相似文献
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夏骥 《云南地理环境研究》2006,18(3):62-66
西部大开发战略的实施为西部地区的发展提供了历史性机遇.西部边疆五省区在西部经济发展中扮演着重要的角色,加快其发展对于西部大开发具有重要意义.西部边疆五省区具有显著的资源优势、区位优势和政策优势,经济发展的潜力巨大;同时,它们在人口、经济、生态环境等方面所面临的一系列共同的问题,又严重阻碍了其发展步伐.因此,如何抓住西部大开发的机遇,制订有效的对策和措施,扬长避短、进一步加快其发展,是西部边疆五省区应认真面对的问题. 相似文献
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Abstract In previous work, a relational data structure aimed at the exchange of spatial data between systems was developed. As this data structure was relational it was of first normal form, but compliance with the higher normal forms was not investigated. Recently, a new procedural method for composing fully normalized data structures from the basic data fields has been developed by H. C. Smith, as an alternative to the process of non-loss decomposition which is difficult to understand. Smith's method has been applied to data fields required to store points, lines and polygons in a chain-node spatial data model. When geographic domain, coverage layer and map are also considered, the procedure naturally leads to a catalogue model, needed for the exchange of spatial data. Although the method produces a fully normalized data structure, it is not as easy to identify which normal forms are responsible for the ultimate arrangement of the data fields into relations, but the benefits of these criteria for data base development also apply to spatial data structures and related ancillary data. 相似文献
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The regulation of the National Significant Seismic Monitoring and Protection Regions(NSSMPR for short) is defined by the Law of the Peoples Republic of China on Protecting Against and Mitigating Earthquake Disasters.The first stage of implementation of the regulation of NSSMPR in the Chinese mainland was finished from 1996 to 2005.The second stage is being carried on from 2006 to 2020.With the support of the National Social Science Foundation,this paper follows up and evaluates the implementation of the regulation of NSSMPR from 1996 to 2012 in the Chinese mainland.Based on analysis of earthquake examples and investigation data,we find that the effect of disaster mitigation is good,and on this basis,some suggestions are proposed to improve the regulation of NSSMPR. 相似文献
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冰芯与寒区环境开放研究实验室的回顾与展望 总被引：1，自引：1，他引：0
对国际和国内冰芯研究的历史与现状,以及冰芯与寒区环境开放研究实验室的硬件（基础建设和仪器设备）和软件（科研力量）方面进行了简介,目前冰芯与寒区环境开研究实验室的三大研究领域：为（１）冰川与大气相互作用过程研究;２）冰芯记录研究;３）雪冰物理学研究,实验室已完成和正承担的课题有３２项,发表论文３００多篇,专著９部,有４项成果获奖,并同国际多家高水平的研究机构合作关系,实验室今后发展目标是,在寒区气候 相似文献
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As an important part of global climate system, the Polar sea ice is effccting on global climate changes through ocean surface radiation balance, mass balance, energy balance as well as the circulating of sea water temperature and salinity. Sea ice research has a centuries - old history. The many correlative sea ice projects were established through the extensive international cooperation during the period from the primary research of intensity and the boaring capacity of sea ice to the development of sea/ice/air coupled model. Based on these reseamhes, the sea ice variety was combined with the global climate change. All research about sea ice includes： the physical properties and processes of sea ice and its snow cover, the ecosystem of sea ice regions, sea ice and upper snow albedo, mass balance of sea ice regions, sea ice and climate coupled model. The simulation suggests that the both of the area and volume of polar sea ice would be reduced in next century. With the developing of the sea ice research, more scientific issues are mentioned. Such as the interaction between sea ice and the other factors of global climate system, the seasonal and regional distribution of polar sea ice thickness, polar sea ice boundary and area variety trends, the growth and melt as well as their influencing factors, the role of the polynya and the sea/air interactions. We should give the best solutions to all of the issues in future sea ice studying. 相似文献
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Lindsay E. Stone Xing Fang Kristine M. Haynes Manuel Helbig John W. Pomeroy Oliver Sonnentag William L. Quinton 《水文研究》2019,33(20):2607-2626
Permafrost degradation in the peat‐rich southern fringe of the discontinuous permafrost zone is catalysing substantial changes to land cover with expansion of permafrost‐free wetlands (bogs and fens) and shrinkage of forest‐dominated permafrost peat plateaux. Predicting discharge from headwater basins in this region depends upon understanding and numerically representing the interactions between storage and discharge within and between the major land cover types and how these interactions are changing. To better understand the implications of advanced permafrost thaw‐induced land cover change on wetland discharge, with all landscape features capable of contributing to drainage networks, the hydrological behaviour of a channel fen sub‐basin in the headwaters of Scotty Creek, Northwest Territories, Canada, dominated by peat plateau–bog complexes, was modelled using the Cold Regions Hydrological Modelling platform for the period of 2009 to 2015. The model construction was based on field water balance observations, and performance was deemed adequate when evaluated against measured water balance components. A sensitivity analysis was conducted to assess the impact of progressive permafrost loss on discharge from the sub‐basin, in which all units of the sub‐basin have the potential to contribute to the drainage network, by incrementally reducing the ratio of wetland to plateau in the modelled sub‐basin. Simulated reductions in permafrost extent decreased total annual discharge from the channel fen by 2.5% for every 10% decrease in permafrost area due to increased surface storage capacity, reduced run‐off efficiency, and increased landscape evapotranspiration. Runoff ratios for the fen hydrological response unit dropped from 0.54 to 0.48 after the simulated 50% permafrost area loss with a substantial reduction of 0.47 to 0.31 during the snowmelt season. The reduction in peat plateau area resulted in decreased seasonal variability in discharge due to changes in the flow path routing, with amplified low flows associated with small increases in subsurface discharge, and decreased peak discharge with large reductions in surface run‐off. 相似文献