Bài viết Khảo sát một số đặc trưng hạn hán ở Việt Nam giai đoạn 1980-2018 sử dụng các chỉ số SPI và SPEI giới thiệu một số đặc trưng hạn hán ở Việt Nam giai đoạn 1980-2018 dựa trên hai chỉ số hạn SPI và SPEI tính với chuỗi số liệu quan trắc từ mạng lưới trạm khí tượng. | VNU Journal of Science Earth and Environmental Sciences Vol. 38 No. 1 2022 71-84 Original Article Investigation of Drought Characteristics Across Vietnam During Period 1980-2018 using SPI and SPEI Drought Indices Tran Quang Duc1 Nguyen Phuong Thao1 Trinh Tuan Long2 Phan Van Tan1 Chu Thi Thu Huong3 Nguyen Van Hiep4 1 VNU University of Science 334 Nguyen Trai Thanh Xuan Hanoi Vietnam 2 Hanoi University of Science and Technology A21 Building 18 Hoang Quoc Viet Cau Giay Hanoi Vietnam 3 Hanoi University of Natureal resources and Environment 41A Phu Dien Bac Tu Liem Hanoi Vietnam 4 Northern Delta Regional Hydro-Meteorological Centre 62 2 Nguyen Chi Thanh Dong Da Hanoi Vietnam Received 13 April 2021 Revised 04 May 2021 Accepted 14 May 2021 Abstract In this study the drought characteristics trend of change and relationship between drought over Vietnam and large scale processes were investigated using drought indices of SPI and SPEI. The monthly mean temperature and precipitation data collected from 146 stations of Vietnam for the period 1980-2018 and datasets of monthly climate indices were used. The drought characteristics including drought frequency drought duration drought severity and drought spatial extent were investigated for three time scales of 3-month 6-month and 12-month droughts. Trend of drought change was estimated using Mann-Kendal test and Sen s slopes. The relationship between drought and large scale processes were examined based on correlation coefficients of drought indices and climate indices as well as their empirical orthogonal functions. The obtanied results showed that there is no distinction between drought characteristics calculated from SPI and SPEI but drought characteristics are significant different among drought time scales. Effects of temperature on drought are only reflected in the trend of change in drought indices. Both SPI and SPEI indices showed that drought frequency and drought duration are larger in the northern sub- regions than .
