黄河三角洲沿岸日潮区的空间分布与潮汐特征

Spatial extent and tidal characteristics of the diurnal tidal zone along the Yellow River Delta coast

该文基于黄河三角洲沿岸实测潮位数据,探讨了研究区域沿岸日潮区的空间分布与潮汐特征。全日潮的潮型特性和潮位曲线形态分析结果表明,黄河三角洲北岸日潮区的西界位于老九井至106沟之间,东岸日潮区的南界位于现行黄河入海口南侧。半日分潮无潮点和潮汐调和常数计算结果表明,众多半日分潮无潮点集合在一定区域而形成黄河口无潮区,致使半日分潮振幅减小,全日分潮振幅上升为主控当地整体潮汐运动的因子。潮汐学理论计算与实测潮位数据统计分析结果表明,大潮和小潮的理论出现时间分别在月赤纬最大和最小的日期;全日潮约占全年时间的三分之二。日潮区的潮差小,大潮与小潮潮差相差悬殊;涨潮历时比落潮长。月平均海面的月际变化、年际变化与年内变化均较大。最高潮面夏半年比冬半年高,最低潮面冬半年比夏半年低。

Based on the observed tidal data along the Yellow River Delta coast in recent years, the spatial extent and tidal characteristics of the diurnal tidal zone are explored. The results demonstrate that the western boundary of the diurnal tidal zone along the north bank of the study area, lies between LaoJiuJin and 106 Gulf. The southern boundary, along the east bank, is in the southern part of the current Yellow River Estuary. It is deduced from the results of amphidromic points calculation and harmonic constant analysis that the amphidromic points of semi-diurnal constituents concentrating near the YRE generate the amphidromic region, which decrease the semi-diurnal constituents, and the diurnal constituents become the primary controls on overall tidal wave movement. From the combined analysis of theoretical calculation and observed data, the tidal characteristics of the diurnal tidal zone show that the spring and neap tides theoretically occur when the moon declination maximizes and minimizes, respectively. Periods of the diurnal tides make up two-thirds of the year, and periods of the semi-diurnal tides constitute the remainder. The tidal ranges are characterized by small tidal ranges and large differences between tidal ranges of the spring and neap tides. The flood tidal duration is longer than the ebb tidal one. The variations of sea level is greatly characterized by inter-monthly, inter-annual and intra-annual variations. The highest tidal level in summer half-years is higher than in winter half-years, and the lowest tidal level in winter half-years is lower than in summer half-years.