长江口芦潮港站年最高潮位一致性分析及修正

在气候变化和人类活动影响下,下垫面情况和水文情势发生变化,用于水文频率分析的水文序列越来越不满足一致性。为了更准确地利用历史水文资料,以长江口芦潮港站1977~2016年潮位序列为例,用10种变异诊断方法进行诊断,将同时存在趋势和跳跃的水文序列进行一致性修正,即先用最小二乘法提取跳跃点前后两个子序列的趋势成分,然后将去趋势后的序列进行基于跳跃的非一致性修正,并将修正前后的潮位序列进行频率计算、对比分析。结果表明,不同重现期下修正后的潮位值相比原始的潮位值均有不同程度的减小,修正后的潮位值更符合当前的水文情势。

Analysis and Correction of Maximum Annual Tide Level of Luchao Port Station in Changjiang Estuary

Under the influence of climate change and human activities, the underlying surface conditions and hydrological situation have been changed, and the hydrological sequences used for hydrological frequency analysis are increasingly inconsistent. In order to make more accurate use of historical hydrological data, this paper takes the tidal sequence of 1977 2016 in the Luchaogang Station of the Yangtze River Estuary as an example, which uses 10 kinds of variation diagnosis methods for diagnosis. The consistency of the hydrological sequence with both trend and jump is modified. Firstly, the trend components of the two subsequences before and after the jump point are extracted by the least squares method. Then the trend based non uniformity correction is performed, and the tidal sequence before and after the modification is calculated and compared. It shows that the modified tidal level values with different return periods have different degrees of reduction compared with the original tidal level values. The corrected tidal level values are more in line with the current hydrological situation.