黄河口高流速区近50年演变过程

HISTORICAL EVOLUTION OF THE HIGH VELOCITY SYSTEM OF THE YELLOW RIVER ESTUARY IN THE PAST 50 YEARS

根据黄河口外大量的现场历史观测资料分析发现,其附近海域流场存在着明显的高流速区。这些高流速区在大时间尺度上随着入海流路的改变以及黄河三角洲的演变也发生着此消彼长的变化。利用ChinaTide潮汐预报软件模拟海域潮汐,并利用不同历史年代的海图资料构建海域地形,通过建立黄河口数学模型分析了黄河口流场特性;利用2015年营口港的潮位资料以及实测流速值对数学模型进行了率定和验证;然后分别利用数学模型,对不同代表年的流场进行模拟复演。计算结果表明:(1)自1962年,黄河口沿岸就已经存在高流速区,分别位于甜水沟和神仙沟口外;(2)1976年,从神仙沟到清水沟一线沿岸存在着多个小型的高流速区群;(3)1996年至今,该阶段内存在3个高流速区,分别位于湾湾沟、神仙沟以及清8口门3个沙嘴处;(4)高流速区的演变与海岸形态的变化存在着密不可分的联系,岸线凸出的沙嘴处往往容易形成平面高流速区。

Historical observation data suggests that high velocity systems occurred outside the Yellow River estuary,and on a large time scale,these high velocity systems change with the alteration of the sea channels and the delta itself.This research aims to establish a mathematical model for the Yellow River estuary by using 3 different nautical charts.The tidal prediction software of＂China Tide＂is adopted to simulate the tide coming offshore.The calculation results show that：（1）since 1962,there have been some high velocity systems outside the estuary,for examples the systems located at the Tianshuigou and Shenxiangou;（2）in 1976,there were a number of small groups of high velocity systems along the coastline;（3）sine 1996,there have been 3 high velocity systems located at the Wanwangou,Shenxiangou and the Qing 8 channel respectively;（4）the change of high velocity system is closely related to the evolution of the coast,and the high velocity regions are always located at the place where protrude spits occur.