Bài báo khoa học

The coastal fringes of the Mekong Delta (CFMD) have been suffered extreme drought events because of a persistent deficiency of rainfall in the context of global warming. This research is conducted to comprehensively assess drought across the CFMD as well as to detect its changing trend over the past four decades. To implement this research, the Standardized Precipitation Index (SPI) is applied to define drought features based on rainfall data sequences obtained from 24 observation stations during the period 1975-2019 while the changing trends in drought were detected applying the Mann-Kendall test and Sen’s slope estimator. The performance of SPI was appraised by comparison with Rainfall Anomaly Index (RAI) through Pearson Product-Moment Correlation (r) and Kappa test (k) statistical methods. The high correlation values (e.g., r ≥ 0.812 and k ≥ 0.283) were confirmed the good performance of the SPI for drought simulation. The results pointed out that the appearance of multiple drought events ranging from moderate to extreme was recorded over the entire study area. A significant upward trend was recorded for drought appearance on both the SPI6-and SPI12-month drought time scales. A significant upward trend of drought is proof of a significant decline in rainfall, with the main occurrence focusing on the western fringe of the study area. In general, drought is more frequent and severe in the western fringe of the area as compared to other locations.