Thi Thanh Hang Phan, Thi Van Huong Do , Thi Bich Nguyen, Hoa Vinh Dang, Tra Mai Ngo, Thi Bich Thuc Pham. Rainfall Distribution in the Srepok River Basin (Vietnam)

DOI: 
https://doi.org/10.15407/ugz2025.01.039
Ukr. Geogr. z. 2025, No. 1:39-46
Ukrainian Geographical Journal 2025 (1) / Український географічний журнал (1)
Language of publication: 
English
Full text: 
PDF icon ugz_2025_1_5_39_46.pdf
Authors: 
Thi Thanh Hang Phan 1, 2  
Thi Van Huong Do 4  
Thi Bich Nguyen 1, 2
Hoa Vinh Dang 3  
Tra Mai Ngo 2, 5  
Thi Bich Thuc Pham 6, 2  
 
1 Institute of Geography, Vietnam Academy of Science and Technology, Hanoi
2 Graduate University of Science and Technology, Vietnam Academy of Science and Technology, Hanoi
3 Ho Chi Minh City Institute of Resources Geography,  Vietnam Academy of Science and Technology, Ho Сhi Minh City
4 Thai Nguyen University, Thai Nguyen
5 Institute of Physic, Vietnam Academy of Science and Technology, Hanoi
6 Institute of Applied Mechanics and Informatics, Vietnam Academy of Science and Technology, Ho Chi Minh City
 

 

Abstract: 

Srepok is an international river basin in the Central Highlands in Vietnam with an area of about 18,230 km2, and is divided into ten irrigation sub-basins. This study applies the statistical method to assess the distribution of rainfall in the past using observed data (1981–2020) and the downscaling method to predict for the periods 2021–2040, 2041–2060, 2061–2080, and 2081–2100 under the medium and high emission scenarios (SSP2-4.5 and SSP3-7.0). Based on observed data, the annual rainfall in 1981–2020 decreased gradually from the North and South to the center and decreased from the West to the East of the basin. Rainfall (May to October) in the rainy season reached 1,494 mm, accounting for 84.4% of annual rainfall. Under both SSP2-4.5 and SSP3-7.0 scenarios, the annual rainfall in the basin and the irrigation sub-basins tends to decrease. The low rainfall area tends to expand every 2 decades to the end of the 21st century. The rainfall amounts do not change between the periods in the dry season but tend to decrease in the rainy season. The rainfall tends to increase from the East to the West of the basin in the rainy season and from the North to the South in the dry season. However, monthly and annual rainfall between periods is relatively stable under the SSP2-4.5 scenario.

Key words: 
rainfall, distribution, Srepok river basin and CMIP6
Pages: 
39-46
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