Các phương pháp kiểm tra định lượng sự đồng nhất của chuỗi số liệu mưa: Áp dụng cho lưu vực sông Cả

Abstract

This paper presents four statistical tests for assessment and quantitative homogeneity of rainfall time series. The daily rainfall data in the period from 1959-2016 at 8 stations in the Ca river basin are used for demonstration of four statistical tests. The computed results show that the statistic value of the cumulative deviations test (Cd), Bayesian test (Ba), Worsley’s ratio test (Wo) varies mainly in the permit range. In detail, the value of Cd changes from 0.396 to 1.640, while the value of Ba ranges between 0.224 and 4.542 as well as the value of Wo varies from 0.074 to 3.970. The rainfall time series at almost stations presents the homogeneity, and thus these data can be used for assessing rainfall variability and trend analysis, as well as for input data in relevant studies. The cumulative deviations test (Cd), Bayesian test (Ba) and Worsley’s ratio test show similar homogeneity results. These tests also depict a clear discrepancy in comparison with results obtained from the von Neumann’s ratio test