DEDUCING THE CHARACTERISTICS OF LARGE-SCALE BEACH TOPOGRAPHIC CHANGE BY COMPLEX PRINCIPAL COMPONENT ANALYSIS

摘要

Complex principal component analysis (CPCA) is applied to a series of topographic survey data obtained in Kashimanada Coast, Japan, in order to investigate the characteristics of the beach topographic change. A new parameter called "local ratio of contribution" was introduced to identify a predominant mode of CPCA to characterise the topographic change at each surveyed point. Consequently, the trend of topographic change on the coast were evaluated in detail by using the temporal and spatial functions as well as the local ratio of contribution.