High-resolution mapping of glacial lake expansion in Kyrgyzstan (2016–2024) using Sentinel-2 imagery

Abstract. Glacial lakes are sensitive indicators of glacier retreat and are important for regional hydrological and hazard assessments. This study presents a high-resolution (10 m) inventory of glacial lakes in Kyrgyzstan for 2022–2024, derived from Sentinel-2 imagery using a semi-automated workflow complemented by manual refinement. A Random Forest classification model trained on the 2022–2024 inventory was applied to 2016–2017 imagery to reconstruct historical lake distributions and analyze changes over an eight-year period. The 2024 inventory includes 2 592 lakes covering 77.6 km², mostly small (<0.05 km²) lakes located between 3 500 and 3 800 m elevation. Between 2016 and 2024, the number of lakes increased by 10.5 % and total lake area by 8.7 %, driven primarily by the formation of small, high-altitude proglacial lakes, whereas larger, lower-elevation lakes remained largely stable. Supraglacial lakes exhibited slight area increases and, on average, an upward shift in elevation, whereas proglacial, and glacier-detached lakes showed minimal changes. Regional trends reveal pronounced heterogeneity, with Issyk-Kul, Batken, and Talas emerging as regions of new lake formation. Comparison with global datasets confirms completeness and reliability of our inventories. These results highlight the ongoing influence of glacier retreat on lake formation and expansion in Kyrgyzstan, providing a robust baseline for hazard assessment, water resource management, and future cryospheric monitoring.