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大风是台风引发的三大灾害之一,考虑到现有的台风大风研究相对较少、预报经验也比较不足,因此对其预报方法进行回顾总结具有十分重要的意义。从经验预报、统计预报、数值模式预报及数值预报产品释用等4个方向梳理了台风大风预报技术的研究与应用现状:天气图、卫星云图和雷达图是经验预报中非常重要的工具;统计预报根据方法的不同可细分为回归预报、客观相似预报和气候持续性预报;数值模式预报方面,国内外多家机构都研发了相应的台风大风预报产品;数值预报产品的释用目前则包含了动力释用、统计释用和人工智能释用。同时总结了上述4类预报方法各自的优势和不足。最后,讨论了未来研究与实际业务中进一步提高台风大风预报能力的可能发展方向。 相似文献
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In this paper,we explore possible conflict between morphological and molecular interpretations of phylogenetic relationships within the well-known peritrichous genus Zoothamnium. On the basis of morphological evidence,for a long time this genus has been believed to be a well-defined monophyletic taxon. Nonetheless,Z oothamnium exhibits higher genetic diversity than the gross morphology of its species. Here,we used all available genetic information for the small subunit of ribosomal RNA(SSU r RNA) and internal transcribed spacer region(ITS1-5.8S-ITS2) for this genus to reconstruct phylogenies for four datasets(SSU rRNA,ITS1,ITS2,and ITS1-5.8S-ITS2) and a combined dataset(SSU rRNA+ITS1-5.8SITS2) using different phylogenetic methods and with consideration of the secondary structure of the genes. Confidence in phylogenetic tree selection was assessed with the approximately unbiased test. The molecular results showed both that Zoothamnium is more likely to be polyphyletic,and morphologically similar genera Zoothamnopsis and Myoschiston were always nested among Zoothamnium species. Accordingly,as with some other groups of ciliates,to understand more fully the correct phylogeny of Zoothamnium there remains a need for additional data from both morphological and molecular studies,covering additional Zoothamnium spp. and members of closely related genera(e.g. Zoothamnopsis,Myoschiston,and Epistylis). 相似文献
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水是人类赖以生存的重要资源,而地下水是工农业生产和居民生活的重要水源,地下水开采量占总用水量的比例也在逐年提高。通过对雄安新区近年地下水埋深资料进行分析,从而确定地下水动态类型、地下水动态变化及主要影响因素,结果显示:雄安新区的地下水动态类型主要是降水入渗—开采型、河湖影响水文型、地下水动态年内变化1-3月降水虽少,为地下水位上升期4-7月为下降期,8-12月为稳定期,年际变化持续下降趋势,影响因素主要为降雨和开采量。从远期看,应防止地下水水位持续下降、提高用水效率的措施,切实加强地下水监测工作。 相似文献
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