Effects of Climate Change on Streamflow in Kon – Ha Thanh River Watershed, Vietnam

Abstract

Climate change is a complex problem and becoming the leading challenge for humankind in the 21st century. It will affect almost aspects of human well-being. Therefore, assessing climate change impacts on water resources and proposed solutions to respond to climate change is urgent and necessary. This study applied the SWAT model (Soil and Water Assessment Tool) and GIS (Geographic Information System) technique to simulate water flows due to the impact of climate change. The models were applied for Kon -Ha Thanh river catchment, located in Vietnam where is considered as one of the countries most affected by climate change. The SWAT model is calibrated and validated well using daily flow data with the Nash-Sutcliffe and correlation coefficients are 0.77 and 0.88, respectively. Two scenarios from Vietnamese government (RCP 4.5 and RCP 8.5) are used to analyze the variation of stream flow in three periods: 2016-2035, 2045-2065, and 2080-2100. The results show that the flow in Kon -Ha Thanh rivers will vary complicatedly and severely under the impact of climate change. This flow may increase roughly 150.8% in flood season and reduce around 11.8% in dry season. Furthermore, the study also demonstrates that there are the changes in the flood dynamics as well as the hydrological shift of this region. This study presents an operational approach to integrate the results from the impacts of climate change to flood protection measures that would be useful in sustainable planning and devising resilience strategies.Vietnam is considered as one of the countries to be severely affected by climate change (Change, 2001). Over 50 years, annual average temperature has increased by 0.5-0.70C, and annual precipitation Engineering

Quantification of Gridded Precipitation Products for the Streamflow Simulation on the Mekong River Basin Using Rainfall Assessment Framework: A Case Study for the Srepok River Subbasin, Central Highland Vietnam

“…In recent years, this well-known watershed-scale model has been used more frequently in the United States, Europe, and other regions [70] due to its high capability to solve hydrological-related issues. Many studies have used SWAT to reveal the impacts of land-use and land cover (LULC), climate change [71], robustness of SPPs [13], and pesticide and agricultural chemical pollutions on streamflow or sediment loads [5,13,48,70,[72][73][74][75][76]. The first version of this model was developed for ArcGIS, as explained by [69,76].…”

Assessment of Urbanization-Induced Land-Use Change and Its Impact on Temperature, Evaporation, and Humidity in Central Vietnam

“…Furthermore, the understanding of urbanization development and its effects on regional temperature during thermal-extreme events is especially critical for coastal regions [40]. This scientific basis is also valuable for streamflow assessment within the context of climate change [41,42]. However, several recent study attempts regarding this topic by [7,25,38,39] for the north midlatitude area of Vietnam (Hanoi city) could not help in this case, in which the chosen study area is the low-land coastal region, Central Vietnam.…”

The role of reservoirs under the impacts of climate change on the Srepok River basin, Central Highlands of Vietnam

“…Numerous studies have highlighted the effects of climate change on the natural water cycle (Bolch et al, 2012;Aryal et al, 2019;Bhatta et al, 2019;Roderick et al, 2019;Tran et al, 2023b). Floods caused by extreme rainfall are expected to become more frequent across the globe (Chattopadhyay et al, 2017;Vo et al, 2018;Ivanov et al, 2021;Tran et al, 2023b), and are likely to persist even more severely in the near future. Besides, Lehner et al (2019) observed that the flow patterns of a third of the world's 200 largest rivers have changed since the 1950s, with these alterations being directly attributable to climate change.…”

“…Although it is challenging to obtain an accurate prediction of streamflow under the climate impacts, it remains a crucial undertaking for effective water resource planning, regional management, and mitigation of extreme events (Khoi and Suetsugi, 2012;Tran et al, 2022c;Tran et al, 2022e;Umar et al, 2022). In Vietnam, a number of studies have investigated the impacts of climate change at various scales (Khoi and Suetsugi, 2012;Ty et al, 2012;Huyen et al, 2017;Vo et al, 2018;Giang and Vy, 2021). However, the majority of these studies were carried out in previous decades with the neglect of important factors (e.g., man-made infrastructures), raising concerns about their reliability which is relevant to the current specifics of climate change in this region.…”

“…The climate inputs for hydrological models, e.g., temperature and precipitation, can be derived using two primary methods: 1) revising records obtained from meteorological stations (Khoi and Suetsugi, 2012;Li and Fang, 2021;Raghavan et al, 2012), and 2) adjusting outputs from climate models (Vo et al, 2018;Tran et al, 2022c). General Circulation Models (GCMs), also known as Global Climate Models, are developed through assumptions and mathematical representations of the physical climate system's processes (Li and Fang, 2021).…”