排序方式： 共有74条查询结果，搜索用时 15 毫秒
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利用大气环流特征量和NCEP/NCAR再分析资料,分析了强热带风暴"碧利斯"造成异常强降水的气候背景。结果表明,冬春季节西太平洋暖池海温偏高时,夏季副热带高压脊线活动偏北,影响中国的热带气旋个数偏多,2006年冬春季海温分布及夏季副高活动形势有利热带气旋影响中国。强热带风暴"碧利斯"登陆和西行时,大气环流高层辐散、低层辐合和热带辐合带的位置偏北、西南暖湿气流在华南有强的辐合等均有利中国南部地区气流辐合上升,使"碧利斯"登陆后低压环流仍能长时间维持,从而造成异常强降水。 相似文献
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Phaeodactylum tricornutum is a potential livestock for the combined production of eicosapentaenoic acid (EPA) and fucoxanthin. In this study, six marine diatom strains identified as P. tricornutum were cultured and their total lipid, fatty acid composition and major photosynthetic pigments determined. It was found that the cell dry weight concentration and mean growth rate ranged between 0.24–0.36 g/L and 0.31–0.33/d, respectively. Among the strains, SCSIO771 presented the highest total lipid content, followed by SCSIO828, and the prominent fatty acids in all strains were C16:0, C16:1, C18:1, and C20:5 (EPA). Polyunsaturated fatty acids, including C16:2, C18:2, and EPA, comprised a significant proportion of the total fatty acids. EPA was markedly high in all strains, with the highest in SCSIO828 at 25.65% of total fatty acids. Fucoxanthin was the most abundant pigment in all strains, with the highest in SCSIO828 as well, at 5.50 mg/g. The collective results suggested that strain SCSIO828 could be considered a good candidate for the concurrent production of EPA and fucoxanthin. 相似文献
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强台风“黑格比”暴雨洪涝特征及成因分析 总被引：3，自引：0，他引：3
利用NCEP/NCAR再分析资料,分析0814号强台风"黑格比"引发华南西南部严重暴雨洪涝特征及其成因.结果显示:①2008年9月下旬副高强度偏强,位置偏北偏西,台风易受其南侧偏东气流引导而西行;②台风"黑格比"强度强,辐合上升运动强烈,触发强降雨;③南海夏季风增强和季风辐合带北抬,西南暖湿气流强盛,增强了辐合上升运动,并为台风降雨带来了源源不断的水汽,使降雨加强和持续;④除了气象因素外,地形对西行台风降雨量的显著增幅作用,是造成强台风"黑格比"暴雨洪涝的重要原因. 相似文献
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邕江洪水的特征及其气候成因研究 总被引：3，自引：2，他引：1
利用邕江洪峰水位、年最高水位资料及邕江流域气象测站逐月降雨量资料,对邕江洪水的特征进行分析表明,洪水多数发生在华南后汛期7～9月,并与流域夏季降雨量密切相关。利用NCEP/NCAR再分析资料以及NOAA卫星观测的OLR资料,分析邕江洪水形成的天气气候条件,研究结果表明:热带气旋影响是邕江发生洪水的主要原因。当西太平洋副热带高压位置偏北,邕江流域易受热带辐合带(ITCZ)影响,对流活跃,热带气旋活动频繁,此时邕江易发生洪水;地形对邕江洪水的形成有较重要的作用;邕江洪水易发生在赤道东太平洋海温为负距平的条件下。分析了邕江洪水气候成因。 相似文献
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在生殖季节从大亚湾采集紫海胆Anthocidariscrassispina ,分离出生殖腺和棘壳 ,用ICP AES法测定其金属元素含量。结果表明 ,紫海胆生殖腺中含有Ca ,Mg ,Sr,Fe ,Mn等1 8种金属元素。这些元素几乎都同样在棘壳中存在 ,而且棘壳中的浓度比生殖腺的高出几十倍到几百倍。同时发现棘壳中金属元素的浓度比海水中的高很多 ,如Fe的浓度为海水的34万倍 ,Mn为 1 4.5万倍 ,说明紫海胆对海水中金属元素有很强的富集作用。结果还表明紫海胆生殖腺中金属元素的含量存在性别差异 ,雌性生殖腺中Zn含量是雄性生殖腺的 4倍 ,而雄性生殖腺中Mg的含量比雌性生殖腺高。以食品卫生标准来衡量 ,大亚湾紫海胆生殖腺金属元素含量完全符合国家标准GBn 2 38 84。如何开发和利用这一海产资源 ,值得深入研究。 相似文献
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西南季风和热带气旋耦合的暴雨过程诊断分析 总被引：1，自引：0，他引：1
本文用NCEP/NCAR再分析资料、常规观测资料、FY-2C卫星云图、风廓线资料及自动站资料分析了热带气旋"碧利斯"的路径、陆上维持、暴雨成因.结果表明:"碧利斯"登陆后折向西行与冷空气到达黄淮一带有关,以后折向西偏南行,是受大陆高压南侧东北气流引导;"碧利斯"在陆上维持长、登陆后具有明显的不对称结构,与它处在鞍形场的有利流场、副热带高压从其东面加强西伸、正值西南季风爆发有关;暴雨的发生,与其"处在有利的气候背景,低压环流以罕见的路径从较北的纬度跨越广西"有关:更重要的是西南季风激发西南急流,西南急流输送水汽和释放潜热,利于热带气旋环流的维持,也为暴雨提供充足的水汽条件;急流轴左侧为正切变涡度区,既有利于热带低压环流的维持,又有利于强对流的发生;急流加强风的垂直切变,促使对流风暴不断生成.强降水的发生与西南急流的加强和向下扩展相关,急流指数变化对暴雨短时临近预报有较好预示性. 相似文献
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This paper comprehensively studies the spatio-temporal characteristics of the frequency of extremely heavy precipitation events over South China by using the daily precipitation data of 110 stations during 1961 to 2008 and the extremely heavy precipitation thresholds determined for different stations by REOF, trend coefficients, linear trend, Mann-Kendall test and variance analysis. The results are shown as follows. The frequency distribution of extremely heavy precipitation is high in the middle of South China and low in the Guangdong coast and western Guangxi. There are three spatial distribution types of extremely heavy precipitation in South China. The consistent anomaly distribution is the main type. Distribution reversed between the east and the west and between the south and the north is also an important type. Extremely heavy precipitation events in South China mainly occurred in the summer-half of the year. Their frequency during this time accounts for 83.7% of the total frequency. In the 1960s and 1980s, extremely heavy precipitation events were less frequent while having an increasing trend from the late 1980s. Their climatological tendency rates decrease in the central and rise in the other areas of South China, and on average the mean series also shows an upward but insignificant trend at all of the stations. South China＇s frequency of extremely heavy precipitation events can be divided into six major areas and each of them shows a different inter-annual trend and three of the representative stations experience abrupt changes by showing remarkable increases in terms of Mann-Kendall tests. 相似文献
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通过对广西1958~2006年88个代表站冬季(12月至次年2月)平均气温的EOF和REOF分析,探讨广西冬季气温异常冷暖年的时空分布结构特征。研究分析冬季气温前期和同期500hPa高度距平场和海温场的特征:异常偏冷年份的前期极涡较强,副高偏弱,亚洲西风带经向度较大,南亚高压较强;到冬季,亚洲中高纬经向环流继续加大,东亚大槽加深南移,南亚仍维持一浅脊。异常暖年的形势恰恰相反。拉尼娜年结束年易出现冬季气温异常偏冷年份,而厄尔尼诺年结束年易出现冬季气温异常偏暖年份。同时,黑潮区气温的变化对广西冬季气温异常有较好的指示作用。 相似文献
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