摘要
利用东京台风中心提供的1971—2020年的西北太平洋热带气旋资料,对南海生成热带气旋的发生频数、发生源地、强度和持续时间、移动路径以及大风分布特征进行统计分析。结果表明:南海热带气旋主要生成于5—12月,其中6—9月为盛行期,约有70%的热带气旋生成;热带气旋生成位置季节变化明显,6—9月多生成于南海北部17°N附近,11月—次年4月多生成于14°N以南的南海南部,5月和10月为季节转换期,生成位置大幅北进或南撤;热带气旋中心最低气压为940~1004 hPa,平均值为985.4 hPa,近中心最大风速为35~85 kt,平均值为48.3 kt,平均持续天数为6.2 d;热带气旋移动路径以西移和西北移路径居多,各月都有发生,其次为东北移路径,主要发生在5—6月;近90%的南海热带气旋10级以上大风以中心呈对称分布,大风圈平均半径为53.2 n mile,在7级以上大风中以中心呈对称分布的略多于不对称分布的,7级大风圈的平均半径为142.3 n mile。
Based on the data of tropical cyclones in the Northwestern Pacific from 1971 to 2020 provided by the Tokyo typhoon center,the occurrence frequency,origin location,intensity and duration,moving path and gale distribution characteristics of tropical cyclones generated in the South China Sea are statistically analyzed.The following main conclusions are obtained:tropical cyclones in the South China Sea mainly occur during May and December,in which June to September is the prevailing period,and the occurrence frequency in these four months accounts for about 70%of annual number.The seasonal variation of the cyclone origins is large.From June to September,cyclones originate near 17°N in the northern South China Sea on average.From November to April of the next year,cyclones originate in the southern South China Sea(south of 14°N).May and October are the seasonal transition periods,and the origin locations of cyclones shift northward or southward significantly;The minimum pressure of the cyclone center is 940~1004 hPa with an average of 985.4 hPa,the maximum wind speed near the cyclone center is 35~85 kt with an average of 48.3 kt,and the average duration is 6.2 d;Most of the cyclones move westward and northwestward during June and December,followed by northeastward during May and June.Strong winds above force 10 associated with nearly 90%of the South China Sea tropical cyclones are symmetrically distributed with respect to the center,and the average radius of the strong wind circle is 53.2 n miles.The symmetrically distributed strong winds above force 7 are slight more than the asymmetrically distributed strong winds above force 7,and the average radius of the strong wind circle is 142.3 n miles.
作者
杨亚新
YANG Yaxin(Department of Navigation,Jiangsu Shipping College,Nantong 226010,China)
出处
《海洋预报》
CSCD
北大核心
2024年第1期104-111,共8页
Marine Forecasts
基金
江苏省教育信息化重点资助项目(20180006)。
关键词
南海
热带气旋
活动规律
大风分布特征
South China Sea
tropical cyclone
activity law
gale distribution characteristics
