A dataset of 190 lakes' ice phenology on the Tibetan Plateau extracted from AMSR2 data

Abstract. The utilization of passive microwave land‒water mixed pixels in extracting lake ice phenology has been underestimated. There are still many small and medium-sized lakes whose ice phenology has not been recorded, especially in regions such as the Tibetan Plateau, for which there are very few in situ observations. In this study, the changing characteristics of mixed pixels during freeze‒thaw processes are discussed. Using air temperature to reduce the seasonal variation in brightness temperature series, Advanced Microwave Scanning Radiometer 2 (AMSR2) data were used to extract the ice phenology of 194 lakes that could represent 78 % of the total lake area on the Tibetan Plateau from September 2012 to August 2022. The lake ice phenology results show high consistency compared with the Moderate Resolution Imaging Spectroradiometer (MODIS)-derived lake ice phenology dataset and demonstrate better performance than the existing AMSR2-derived dataset. This ice phenology dataset covers the largest number of lakes in the Tibetan Plateau region, fills a gap or increases the integrity of ice phenology records for at least one hundred small lakes and provides complete pixel-scale freeze‒thaw processes on the lake surface. The dataset will provide valuable information to the user community about the spatial distribution of and changes in ice cover in lakes, especially small lakes, over the last decade. The dataset is available at https://doi.org/10.11888/Cryos.tpdc.300796 (Cai and Ke, 2023).