南沙永暑海区潮汐特征分析  

Analysis on the Tide Characteristics at the Yongshu Reef of the Nansha Islands

作　　者：李维锋[1,2] 梁广健 徐刚 

机构地区：[1]中国海洋大学海洋环境学院 [2]海军91878部队 [3]南海舰队海洋水文气象中心 [4]海军91561部队

出　　处：《海洋技术》2014年第5期71-77,共7页Ocean Technology

摘　　要：文中对永暑礁海域1988—2011年逐时潮位、风速、气压等观测资料进行统计分析,讨论该海区的潮汐特征。结果表明,南沙海区全日分潮大于半日潮,属不规则日潮,9月平均海平面最高,1月最低,该海区年平均海平面具有上升趋势,上升率为0.16 cm/a,月平均海平面与气压具有显著相关性,月平均潮差与风速具有显著相关性,平均海平面具有1 a的季节变化周期。采用M-K检验法分析该海域年平均海平面的突变特征,突变点为2001年和2008年。功率谱方法得出月平均海平面变化的显著周期为1 a,表明海平面的季节变化是该海域潮汐的主要特征。此外,利用潮位频率分布得到海区设计高水位为75 cm,设计低水位为-85 cm,同时第一型极值分布曲线较好地拟合了南沙海区年最高水位的分布,50 a一遇高水位为120 cm,低水位为-152 cm,给海洋工程设计提供了可参考的设计参数。Based on the observed tide, wind and atmospheric pressure data at the Yongshu Reef from 1988 to 2011 are analyzed to discuss the characteristics of tide at the Nansha sea area. The results show that the tide at Nansha is classified as irregular diurnal tide, with the main diurnal constituents larger than the main semi-diurnal constituents. The highest mean sea level appears in September and the lowest in January. It is calculated that the annual mean sea level arises at the rate of 0.16/a. Meanwhile, there is significant correlation between monthly mean sea level and air pressure, and correlation also exists between monthly average tidal range and wind speed. It is clear that the mean sea level of the Nansha sea area has a seasonal variation cycle of 1 a. The M-K testing method is adopted to analyze the mutation features of annual mean sea level of this sea area, with the mutation points at 2001 and 2005. Through power spectrum, it is derived that monthly mean sea level changes with a significant cycle of 1 a, indicating that seasonal changes of sea level are the main features of tide in this sea area. In addition, using the frequency distribution of tidal waters, it is calculated that the designed high water level is 75 cm and the designed low level is -85 cm, while the first type of extreme value distribution curve fits well with the distribution of the annual maximum water level in the Nansha sea area, with once-in-5-decade high level of 120 cm and low level of -152 cm, providing a reference of design parameters for marine engineering design.

关 键 词：南沙海区 潮汐 调和常数 非调和常数 极值水位 

分 类 号：P731.23[天文地球—海洋科学]