基于潮汐模型与余水位监控法的海图测量水位改正及应用

Water Level Correction in Chart Measurement by Using Tidal Model and Residual Water Level Monitoring Method

面对近年海图测量逐渐由近海向外延伸的发展现状,其对水位改正的要求越来越高,水位改正是海图测量中的一个尤为重要的技术环节,对保证测量精度起着极其重要作用。实际测量作业中,在一些潮汐性质变化复杂的海域,采用传统水位改正方法面临设站数量多、难度大、易丢失、精度难保证等难点。针对测区潮波分布的复杂性与特殊性,基于POM模式,采用"混合"同化法同化由T/P卫星测高数据反演的沿迹潮汐参数构建了高分辨率高精度的潮汐模型,利用余水位的空间相关性,称之为基于潮汐模型与余水位监控的水位改正法。通过海图测量实例中基于潮汐模型与余水位监控法的应用,对测量成果精度进行了分析和验证,为海图测量在水位改正方法的选择提供了技术支持,进而对保证测量精度有着重要的现实意义。

The chart measurement expands gradually beyond offshore in recent years so that the requirement for water level correction becomes increasingly higher.The water level correction is a particularly important technical link in chart measurement and plays an extremely important role in ensuring the measurement accuracy.In the practical measurements,the traditional water correction methods have faced to the difficulties such as large number of stations designed,hardly to operate,low accuracy,easily to lose,and so on,particularly in the areas where tidal property changes complicatedly.On account of the complexity and particularity of the tidal wave distribution,a water level correction method which is based on tidal model and residual water level monitoring is proposed,in which the tidal model has high resolution and is established based on the POM model and by using "hybrid"assimilation method to assimilate the tidal parameters inverted from the altimeter data measured by T/P satellite.In addition,the spatial correlation of the residual water level is also used for the method.By applying this method in an example of practical chart measurement,the accuracy of the measurement is analyzed and verified.This method can provide a technical support for the water level correction in the chart measurement and has a great significance for ensuring the measurement accuracy.