Monitoring the water clarity of lakes is essential for the sustainable development of human society. However, existing water clarity assessments in China have mostly focused on lakes with areas > 1 km2, and the monitoring periods were mainly in the 21st century. In order to improve the understanding of spatiotemporal variations in lake clarity across China, based on the Google Earth Engine (GEE) cloud platform, a 30 m long-term LAke Water Secchi Depth (SD) dataset (LAWSD30) of China (1985–2020) was developed using Landsat series imagery and a robust water-color-parameter-based SD model. Noted, the LAWSD30 has been updated to 2021 using Landsat data from 2020 to 2022. The details are described in "30 m long-term LAke Water Secchi depth (SD) dataset (LAWSD30) of China (1985–2021)_Readme_V1.1.docx".

{"references": ["Chen, X., Liu, L., Zhang, X., Li, J., Wang, S., Gao, Y., and Mi, J. (2022). Long-term water clarity patterns of lakes across China using Landsat series imagery from 1985 to 2020. Hydrol. Earth Syst. Sci., 26, 3517\u20133536.", "Chen, X., Liu, L., Zhang, X., Li, J., & Song, K. (2021). An assessment of water color for inland water in China using a Landsat 8-derived Forel-Ule index and the Google Earth Engine platform. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, PP(99), 1-1"]}