Future impacts of water abstraction and climate change on Shortandy Lake, Kazakhstan

Central Asia’s semi-arid and arid regions are vulnerable to climate change due to limited water resources and fragile ecosystems. This study uses a water balance model to assess climate change impacts on Shortandy Lake in Burabay National Nature Park (BNNP), an endorheic system typical of semi-arid regions, providing insights into their behavior under changing climatic conditions. Using the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP2b) framework, this study employs two bias-adjusted Global Climate Models (GCMs) from the CMIP5 ensemble, GFDL-ESM2M (GFDL) and IPSL-CM5A-LR (IPSL), under Representative Concentration Pathway (RCP) 2.6 and RCP6.0 scenarios, with a monthly lake water balance model, to assess lake storage variability in Shortandy Lake under three abstraction scenarios by 2100. Precipitation is projected to increase with the GFDL model and decrease with IPSL. With both GCMs, rainfall-generated runoff is the primary contributor to future lake storage, while increases in lake evaporation significantly increase water losses from the lake surface. By 2100, lake volume is projected to decline by 38%–33% (GFDL) and 77%–82% (IPSL) under current abstraction limits. This study demonstrates the critical role of setting abstraction limits, as their removal could lead to the lake drying up by the 2070s (IPSL) under both RCP scenarios due to the combined pressures of abstraction and climate change. The findings highlight the significant impact of future climate change on BNNP and the importance of effective water management policies. A lack of observed groundwater data for the BNNP area precludes its representation in the lake water balance model, which highlights the need for enhanced groundwater monitoring in the region so that groundwater flux can be included in future simulation studies.