Pelevin, V., Koltsova, E., Molkov, A., Fedorov, S., Alymkulov, S., Konovalov, B., Alymkulova, M., Jumaliev, K.
The development of regional satellite bio-optical models for natural waters with high temporal and spatial variability, such as inland seas, reservoirs, and coastal ocean waters, requires an intermediate measuring link in the chain from water sampling to bio-optical models. The most crucial requirements are high-precision measurement of the main water-quality parameters — chlorophyll a (Chl a), coloured dissolved organic matter (CDOM), and total suspended sediment (TSS) in the upper water layer — together with a high operational rate and the ability to cover a large area in the short time of a satellite overpass. A possible solution is to use laser-induced fluorescence (LIF) of water constituents measured by a marine LiDAR in situ at a high sampling rate from a high-speed vessel. This method was applied to the oligotrophic Issyk-Kul Lake in Kyrgyzstan, where more than 4000 and 1000 match-ups were obtained for Chl a and TSS respectively. New preliminary regional bio-optical models were developed from a one-day survey and tested against archive Sentinel-2A data for 2022, demonstrating the method for water bodies across a wide trophic range.