Abstract: Lake ice phenology is considered a sensitive indicator of regional climate change. Qinghai Lake is the largest saltwater lake in China and its characteristics and changes of lake ice phenology have been paid more attentions. Based on multi-source remote sensing (RS) datasets including the MOD09GQ surface reflectance product and Landsat TM/ETM+/OLI images, a dataset of ice phenology of Qinghai Lake from 2000 to 2018 was built by using RS and GIS technology. Due to the spectra differences between lake ice and lake water, the method of threshold segmentation which combined reflectance of the red band with the reflectance difference between the red and near-infrared bands was adopted to extract the ice area of Qinghai Lake based on MOD09GQ product. Meanwhile, the artificial visual interpretation results of lake ice based on Landsat TM/ETM+/OLI images was used to verify the corresponding lake ice area based on MOD09GQ product, which showed the relative error was only 0.8%. This dataset includes the vector boundary, the area ratio, phenology information of lake ice and water area of Qinghai Lake from 2000 to 2018. Specifically, the lake ice phenology information of Qinghai Lake involves the dates of the lake freeze-up start, freeze-up end, break-up start, break-up end and completely freezing duration, etc. This dataset can provide an important reference for exploring the spatio-temporal characteristics of lake ice of Qinghai Lake and the response of lake ice to climate change.
Keywords: Qinghai Lake; MODIS; Lake ice phenology; Threshold method