Multi-source method for analysing ice cover phenology of high-altitude (High Tatra Mts.) lakes

This paper presents a multi-source analysis for studying lake ice cover phenology in the high mountain environment. For the study, two lakes located in the High Tatra Mts. (southern side belonging to Slovakia), were selected. The combination of optical satellite imagery (Sentinel-2) and webcam images from meteorological stations (Avalanche Prevention Centre, MRS of the SR) with a direct view of these lakes was used. Such approach compensates for the technological limitations of separate methods and the limitations of this specific environment. It allowed for the first time to determine in detail the individual phenological phases of freezing, thawing/breaking and duration of lake ice cover on the Slovak side of this mountain range. The method might be generally applicable in high-altitude lakes which are difficult to access, small in size, and located in an area of high cloud cover, but represent a significant part of the high mountain cryosphere.