Future changes in hydro-climatic extremes in the Upper Indus, Ganges, and Brahmaputra River basins

Understanding how climate change affects water availability is a pressing challenge. Prior research has shown that temperature and precipitation patterns influence river discharge. However, the specific effects on extreme hydrological events remain unclear. This uncertainty drives the need for detailed modeling in sensitive regions. The Hindu Kush-Himalayan region is particularly vulnerable to such changes. Existing models often lack the resolution to capture localized impacts. This gap motivated the use of a cryospheric-hydrological model. The study aims to bridge the knowledge gap in future flood and drought risks.

This study investigates the potential effects of climate change on future hydrological extremes. The focus is on the Indus, Ganges, and Brahmaputra River basins. These regions are critical for water supply and agriculture. The goal is to evaluate how climate change might alter extreme events. The study uses a cryospheric-hydrological model to simulate future conditions. The model is driven by downscaled climate projections. The aim is to assess changes in both high and low flow conditions. The results may help inform water management strategies in the region.

A fully-distributed cryospheric-hydrological model was used to simulate current and future conditions. The model was calibrated using observed daily discharge data. Geodetic mass balances were also used to improve accuracy. Eight downscaled General Circulation Models were selected for climate forcing. The models were based on RCP4.5 and RCP8.5 scenarios. The study focused on changes in climatic and hydrological extremes. High and low flow conditions were analyzed to assess future risks. The ensemble approach allowed for a range of climate projections to be considered.

Future climatic extremes are expected to increase more than climatic means by the end of the century. High flow conditions are projected to rise significantly under both RCP scenarios. Precipitation extremes appear to be the main driver of increased discharge. Temperature extremes may also contribute, but their impact is less certain. Low flow conditions may decrease in frequency, though uncertainties remain high. The magnitude of change varies depending on the climate scenario. The study highlights the potential for more frequent and intense flooding. These findings may help improve flood risk assessments in the region.

The study suggests that climate change may lead to more frequent and intense hydrological extremes. Increases in high flow conditions are likely due to precipitation changes. Temperature extremes may also play a role, but their effect is less clear. Low flow conditions may become less common, though projections are uncertain. The results may help improve understanding of future water risks. The Hindu Kush-Himalayan region is particularly vulnerable to these changes. The study highlights the need for adaptive water management strategies. These findings may support future research on climate-water interactions.