Assessment of climate change impact on water availability in the upper Dong Nai River Basin, Vietnam

Abstract

On a global scale, climate change is projected to have detrimental impacts on water availability. This situation will become more severe owing to accumulated impacts of climate change and anthropogenic activities. This study aims to investigate climate change impact on water availability in the upper Dong Nai River Basin using the Soil and Water Assessment Tool (SWAT) and Water Evaluation and Planning (WEAP) models. Future rainfall scenarios were downscaled from five different general circulation models under RCP4.5 and RCP8.5 using the Long Ashton Research Station Weather Generator (LARS-WG) tool. Under the climate change impact, annual river discharge in the study region is generally projected to have upward trends in the future, except for the near-future period of 2030s under RCP4.5. In addition, dry-seasonal river discharge is expected to be increased in the future. Considering the baseline condition of water use, there was an annual water shortage of approximately 32.9 × 103 m3, which mostly occurred in the dry season from January to March. Climate change may reduce the water shortage in the study region ranging from 7.0 to 30.1% in the future. Under the combined impacts of climate change and increasing water demand, the water shortage will vary from −18.6 to 6.0% in the future. The results can provide valuable insights to implement appropriate future water resources planning and management in the study region.

Climate change impact on water resources availability in the kiltie watershed, Lake Tana sub-basin, Ethiopia

“…This study reveals dry season water availability declines and rainy season water availability increases, which is in contrast to other studies by Ref. [ 25 ] in the Dong Nai River Basin in Vietnam that show dry season water availability increases. Due to the use of various GCM-RCM models and climate scenarios with vastly different levels of resolution and emission rate, the results of this study and previous ones have varied.…”

Estimating Future Surface Water Availability Through an Integrated Climate‐Hydrology‐Management Modeling Framework at a Basin Scale Under CMIP6 Scenarios

“…Khoi et al. (2021) studied the impacts of climate change on water availability in the upper Dong Nai River Basin using the SWAT and Water Evaluation and Planning models. However, the SWAT model is a semi‐distributed hydrological model that does not consider the physical process of reservoir evaporation—which is of great importance in water resources management, but is often overlooked in the current modeling communities.…”

“…For example, Muttiah and Wurbs (2002) used the Soil and Water Assessment Tool (SWAT) and WRAP models to investigate the impacts of climate change on water supply reliability in the San Jacinto River Basin, Texas. Khoi et al (2021) studied the impacts of climate change on water availability in the upper Dong Nai River Basin using the SWAT and Water Evaluation and Planning models. However, the SWAT model is a semi-distributed hydrological model that does not consider the physical process of reservoir evaporation-which is of great importance in water resources management, but is often overlooked in the current modeling communities.…”

The climate change effects on agricultural drought in the Be River Basin

“…The WEF Global Risks Report for 2021 identified climate change as one of the greatest risks to socioeconomic development or daily life. Numerous studies claimed that changes in rainfall patterns and rising temperatures will have a substantial impact on water resources, changing runoff and transport of pollutants (Duan et al, 2021;Khoi et al, 2021). As evidenced by the drought episode that occurred in Vietnam from 2015 to 2017, climate change also influences the El Niño Southern Oscillation (ENSO) which affects the incidence of drought (WB, 2021).…”