大沽河口水位变化特征分析

本文基于2016年11月8日—2019年6月29日大沽河入海口水深观测数据分析了大沽河河口水位变化特征,并结合风场、降水量、卫星高度计融合产品资料对其影响因素展开了讨论。结果表明:1)大沽河口水位变化由潮汐过程主导,潮汐类型为正规半日潮,M2分潮占主导;2)余水位在2017年7月—2019年1月存在周期约为110—150天的显著季节内变化,主要受到纬向风的影响,监测系统处在大沽河入海口西岸,东向(西向)风将驱动水体向东(西)输运,导致西岸监测系统处水量减少(增加),从而观测到余水位下降(上升);3)观测期间,余水位存在显著下降趋势,约为–0.53×10–2 m/月,主要受到大沽河流域降水量减少的影响。

Analysis of the characteristics of water level variation in Dagu River estuary

Based on the depth observation data of Dagu estuary from November 8, 2016 to June 29, 2019, this paper analyzed the characteristics of the water level change in Dagu estuary, its influencing factors were discussed combined with wind filed, precipitation and satellite altimeter fusion data. The results showed that: 1) the water level variation in Dagu estuary was dominated by tidal process, whose type is normal semi-diumal tide, and the M2 subtide was dominant; 2) The residual water level had a significant intra-seasonal period of approximately 110~150 days which was mainly affected by the zonal wind, eastward (westward) wind would drive the water transporting to the east (west), resulting in a decrease (increase) in water volume at the west bank where the monitoring system was, so the residual water level was observed to decrease (rise); 3) during the observation period, the residual water level has a significant downward trend, about -0.53×10-2 m per month, which was mainly affected by the decrease in precipitation in the Dagu River basin. By analyzing the characteristics of water level variation and its dynamic process in Dagu estuary, it had important theoretical value and guiding significance for the project construction and ecological protection of the estuary.