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701.
HUANG DanQing ZHU Jian & KUANG XueYuan School of Atmospheric Sciences Nanjing University Nanjing China 《科学通报(英文版)》2011,(Z1):424-431
The features of the decadal evolution of different durations of continuous Meiyu precipitation and their possible cause from the viewpoint of the low-level intraseasonal oscillation(ISO) are examined in this study. It is found that the total frequency of Meiyu precipitation events of certain duration gradually decreases as the duration of the events increases,and the main center of the events moves from the northern Yangtze-Huaihe River Valley(YHRV) to the southern YHRV. The linear trends of different durations of continuous Meiyu precipitation indicate that longer-duration precipitation has become significantly less frequent since 2000,while 2-day and 3-4-day continuous precipitation processes have become more frequent. At the same time,a close relationship between the variation in the low-level ISO and the decadal evolution of frequency of longer-duration Meiyu precipitation is detected. Clearly,since 2000,the low-level ISO has significantly decreased,and a single peak of longer-duration events has been replaced by several peaks of shorter-duration events,which has resulted in a significant decrease in the frequency of longer-duration precipitation. Meanwhile,low-level baroclinicity increased(decreased) during each period,which is in accordance with the increasing(decreasing) frequency of longer-duration precipitation. It is confirmed that longer-duration precipitation has significantly decreased in recent years. 相似文献
702.
LUO ZheXian Key Laboratory of Meteorological Disaster of Ministry of Education Nanjing University of Information Science Technology Nanjing China Wuxi Research Center of Environmental Science Technology Wuxi 《科学通报(英文版)》2011,(25)
Energy dispersion is a fundamental scientific problem in the study of natural disasters such as typhoons, heavy rain and earthquakes. The problem has been addressed by both multi-discipline research and forecast studies. The dynamics of isolated circular vortex energy dispersion have been solved. However, the disastrous results of typhoons and heavy rain often occur due to non-isolated circular vortices, the dynamics of which are explored in this paper. The energy dispersion characteristics of non-isolated ... 相似文献
703.
对苏北部分中小学体育教师非学历继续教育特征研究 总被引:1,自引:1,他引:0
通过文献资料法、问卷调查法、专家访谈法等研究方法,对苏北部分中小学体育教师非学历继续教育动机、次数、时间、途径、内容、存在问题等方面进行调查与分析,并提出相应建议,以期为提高江苏省中小学体育教师非学历继续教育质量尽绵薄之力。 相似文献