东沙群岛附近海域风候特征分析

Wind Climate Characteristics in the Dongsha Islands

目的利用近22年的CCMP(Cross-Calibrated,Multi-Platform)风场资料,对东沙群岛海域的风候特征进行深入研究,为军地海洋建设提供科学依据。方法利用具有高精度的CCMP风场资料,统计分析近22年期间东沙群岛附近海域的风候特征。结果东沙群岛附近海域的海表风速呈"W"状双峰型月变化。峰值出现在11、12和1月期间,海表风速在9 m/s左右,次峰值位于6月,海表风速在6 m/s左右,东沙海域的年平均风速为6.5 m/s。东沙海域的海表风速表现出"U"型日变化特征。东沙附近海域的风速主要分布于3~5级,即3.4~10.7 m/s之间,1月的大风频率明显高于7月。1月和10月,东沙附近海域的风向以NE向为主,7月受西南季风影响显著,风向以S-SW向为主,4月风向则以ENE和SSE向为主。从全年来看,风向以偏东北向为主,S-SW向居其次。在近22年期间,东沙海域的海表风速整体上以0.0424 m/(s·a)的速度显著性逐年线性递增。结论运用高精度的CCMP风场资料,通过统计分析方法得到了东沙群岛海域的风候特征,对军地海战场环境建设具有科学支持作用。

Objective To research wind climate characteristics of the Dongsha Island based on the 22-year CCMP(Cross-Calibrated,Multi-Platform)wind data to provide scientific basis for construction of marine battlefield environment.Methods CCMP wind field data with high accuracy was used to statistically analyze characteristics of the sea area near the Dongsha Islands during the past 22 years.Results The monthly characteristics of the wind speed showed a"W"shape.And the peak value appeared in November-December-January(of about 9 m/s),while the trough appeared in June(of about 6 m/s).The annual mean wind speed was 6.5 m/s.The daily characteristics of the wind speed showed a"U"shape.The wind class of Dongsha Islands was mainly in class 3-5.The gale occurrence in January was greater than that in July.In January and October,the wind direction was northeast,south-southwest in July,while ENE and SSE in April.About the annual occurrence,the wind direction was prevailed by northeast,followed by south-southwest.For the past 22 years,the wind speed of the Dongsha Island showed a significant increasing trend,of 0.0424 m/(s·a).Conclusion With the high-precision CCMP wind field data,the wind characteristics of the Dongsha Islands are obtained through statistical analysis methods,which has scientific support for the construction of the marine battlefield environment.