Capability Analysis of Lake Extent Monitoring in Highland Region from MERSI-II onboard FY-3D

Objectives: Lakes on the Tibetan Plateau are sensitive indicators of global climate change, and relevant studies on lakes are important for exploring the natural evolution of lakes and their interactions with climate. Since climate change, precipitation, glacial melt, and evaporation on the highland areas can easily cause abrupt changes in lake extent, both temporal and spatial resolution are frequently needed in the images used for dynamic monitoring of highland lakes. The Moderate Resolution Imager (MERSI-II) aboard domestic FengYun(FY) satellite provides extensive coverage every day, it has not yet been verified whether its 250 m image can be used for highland lake monitorin. Methods: By using the monitoring data from contemporaneous third-party datasets and Landsat-8 Operational Land Imager (OLI) as the true value in the lakes on the Tibetan Plateau, this paper analyzed the applicability of FY-3D MERSI-II data for plateau lake monitoring. Results: It was found that the average accuracy of MERSI-II images for lake area quantification accuracy reaches 95.12%, and the average lake boundary fitness reaches 91.21%. With the advantage of high-frequency monitoring, long time series of highly dynamic water monitoring applications can benefit from MERSI-II images. To further confirm the application potential of MERSIII data, the effects of improved spatial quality on increases in lake-wide monitoring capacity were analyzed. Compared to the initial results, the application performance of optimized MERSI-II data had significantly improved with an average lake area quantification accuracy of 2.62% and an average lake boundary fitness of 4.53%. For its spatial resolution hyper-segmentation potential and quantitative lake monitoring capability, FY-3D has good potential for high-frequency lake monitoring applications.