区域海面变化研究受到验潮站数据时段不一致、空间分布不均匀及影响要素复杂性和不确定性等因素制约。本文基于西北太平洋海域22个站位的验潮数据,应用RegEM及MTM方法探讨其多尺度波动过程的时空差异,基于空间邻近性及有序聚类方法,将区域海面变化划分为5个区段(渤海—黄海北部沿岸、黄—东海中国沿岸、东海海域日本沿岸、东海南部沿岸以及南海西北部沿岸),进而利用MGF方法对各站位进行中长期的统计预测,并结合主成分方法进行区域综合。结果显示各区2001-2030年的海面变化平均速率分别为:1.23~1.27mm/a,3.30~3.34mm/a,2.72~2.76mm/a,1.43~1.47mm/a和1.13~1.15mm/a,而区域海面上升速率为2.01~2.11mm/a。
Due to the impacts of the inconsistent data timespan,the heterogeneous spatial distribution,and the complexity and uncertainty of sea level change etc.,it is difficult to conduct regional sea-level change researches..Based on the 22 tidal gauge station records in Northwest Pacific ocean marginal sea,the regularized EM algorithm(RegEM) and the Multi-Taper spectral Method(MTM) are adopted to discuss their multi-scale fluctuation processes and their spatial-temporal variations.Integrating orderly cluster and the space adjacent relation of gauge stations,the whole research area is generally divided into five sub-regions,there are Bohai Sea-the coast of the northern Yellow Sea,Yellow-East China Sea near the coast of China,the East China Sea near the coast of Japan,the southern East China Sea and the northwestern South China Sea.Then Mean Generation Function(MGF) is used to predict the medium and long-term trends of each tide station,and Principal Component Analysis(PCA) is employed to obtain regional-scale sea level change trends.The result shows that the sea-level rise rates of five sub-regions from 2001 to 2030 are 1.23-1.27 mm/a,3.30-3.34 mm/a,2.72-2.76 mm/a,1.43-1.47 mm/a and 1.13-1.15 mm/a respectively,and the whole region sea-level rise rate is changed between 2.01 mm/a and 2.11 mm/a.By introducing spatial-temporal variation and multi-scale pedigree characteristic analysis,our work is an attempt of the integrated research on sea-level change characteristic and its prediction.