不同时段下海平面相关参数的差异分析

验潮站观测的海面高度数据是监测海平面变化以及确定平均海面时常使用的重要基础观测信息,针对平均海面以及相对海平面变化速率在不同时段观测资料下结果的差异进行了分析,统计了不同时间尺度平均海面确定的差异,并设计了两组数据实验,具体讨论了不同年份19年观测以及观测时长逐年累加两种情况下,相对海平面变化速率确定结果的规律。实验结果表明,月平均海面具有明显的季节性变化,最大互差可达几十厘米,1年平均海面基本稳定,19年平均海面精度可达厘米级;利用19年的观测资料确定的相对海平面变化速率反映的观测时段内海平面的变化情况,各时段结果差异较大且可靠性较低;为获得稳定可靠的相对海平面变化速率,观测时长应至少涵盖两个潮汐变化周期。

Analysis of Sea Level Related Parameters in Different Periods

Sea level data observed by tide gauge station is an important basic observation information often used to monitor sea level changes and determine the mean sea level (MSL).This paper analyzes the differences of the results of MSL and the relative sea level trends (RSLT) determined by the observation in different time periods,counts the differences of the determination of MSL in different time scales,and designs two sets of data experiments to specifically discuss the law of the determination results of RSLT under the conditions of 19 years of observation in different years and the accumulation of observation time periods year by year.The experimental results show that the monthly MSL has obvious seasonal changes,the maximum mutual difference can reach several tens of centimeters,the one-year MSL is basically stable,and the 19-year average sea surface accuracy can reach centimeter level.The trends of sea level in the observation period reflected by the relative sea level change rate determined by the observation data of 19 years shows great difference and low reliability in the results of each period.In order to obtain a stable and reliable RSLT,the observation period should cover at least two tidal change periods.