Overview

• The study reconstructs 1,300 years of Ganges discharge using climate-model data to place recent trends in long-term context.
• Weakened summer monsoon linked to Indian Ocean warming and pollutant emissions is identified as a key factor in reduced flow.
• Shrinking Himalayan glaciers, altered precipitation patterns, and intensified extraction for farms and cities compound the decline.
• Drought impacts since the 1990s were calculated to be 76% more intense than a comparable 16th-century event.
• Exceptionally low levels in 2015–2017 disrupted drinking water, power generation, irrigation, and navigation, affecting over 120 million people.