Impact of climate change on irrigation water requirements for coffee plants in the fruit development stage: a case study of Dak Lak and Gia Lai provinces in the Central Highlands of Vietnam

This research investigates the impact of climate change on the irrigation water requirements for coffee plants in the fruit development stage in Gia Lai and Dak Lak provinces, Vietnam. Observation data were collected from four meteorological stations, namely, An Khe, Pleiku, Buon Ma Thuot, and Buon Ho. To simulate future scenarios, five CMIP6 models (BBC-CSM2-MR, CanESM5, GFDL-ESM4, MIROC6, and MPIESM1.2-HR) were used with the SSP24.5 scenario for the years 2030-2049 and 20802099. The irrigation water requirements were calculated by the Cropwat model version 8.0. For 2030-2049, the simulation results of BCC-CSM2-MR at An Khe showed the highest increase of approximately 90 mm, while CanESM5 displayed only a 4 mm rise. On the other hand, both MIROC6 and MPI-ESM1.2-HR indicated a slight reduction, ranging from 4 to 10 mm at all stations. For 20802099, the BBC-CSM2-MR model at An Khe recorded the highest increase of 100 mm, whereas the GFDL-ESM4 model showed a decline of 90 mm at Buon Ho. Other models showed a fluctuation increase from 40 to 60 mm. This means that climate change has a significant impact on the irrigation water requirements for coffee plants in the Central Highlands of Vietnam. HIGHLIGHTS Five CMIP6 global climate models and the bias correction and spatial disaggregation method have been used to improve the resolution to get future data (rainfall and temperature).; Finding the variations of irrigation water requirements for coffee plants in the fruit development stage (the major industrial crop of this region) in Dak Lak and Gia Lai Provinces, the Central Highlands of Vietnam was warranted in this study. This area is affected heavily by climate change.;