Attribution analysis demonstrates a 5.1-meter water-level decline in Yamdrok Lake, indicating progressive warming and hydropower drive a persistent water deficit.
Key Points
To identify the key drivers of water-level changes in Yamdrok Lake from 2000 to 2023 and quantify the relative statistical explanatory power of climate change versus hydropower operations.
Synthesized 24 years of hydrological, meteorological, remote-sensing, and hydropower-generation data.
Applied cumulative anomaly analysis and multiple linear regression using rainfall, evaporation, temperature, glacier meltwater, and electricity generation as predictors.
Employed Shapley R² decomposition to evaluate the proportion of variance in interannual lake-level changes (ΔH) explained across operational (2000–2014) and non-operational (2015–2023) periods.
Annual mean lake level fell by a cumulative 5.1 m during 2000–2023, while basin temperatures rose significantly at 0.03 °C yr⁻¹ (p < 0.05) and glacier area shrank by approximately 30.5 km².
During the 2000–2014 hydropower-operation period, five drivers jointly explained 84.51% of variance in ΔH, led by hydropower intensity (32.32%), temperature (27.98%), and glacier meltwater (26.54%).
During the 2015–2023 non-operation period, rising temperature remained the primary driver, accounting for 34.3% to 49.5% of explained variance through direct surface evaporation and loss of glacier recharge resilience.