Evaluating Landsat-8 and Sentinel-2 Data Consistency for High Spatiotemporal Inland and Coastal Water Quality Monitoring

The synergy of fine-to-moderate-resolutin (i.e., 10–60 m) satellite data the Landsat-8 Operational Land Imager (OLI) and Sentinel-2 Multispectral Instrument (MSI) provides a possibility to monitor dynamics sensitive aquatic systems. However, it is imperative assess spectral consistency both sensors before developing new algorithms for their combined use. This study evaluates between OLI MSI-A/B, mainly in terms top-of-atmosphere reflectance (ρt), Rayleigh-corrected (ρrc), remote-sensing (Rrs). To check under various atmospheric conditions, near-simultaneous same-day overpass images MSI-A/B were selected over diverse coastal inland areas across Mainland China Hong Kong. results showed that obtained from consistent. difference mean absolute percentage error (MAPE) MSI-A products was ~8% ρt ~10% ρrc Rrs all matching bands, whereas MAPE MSI-B ~3.7% ρt, ~5.7% ρrc, ~7.5% visible bands except ultra-blue band. Overall, green band most consistent, with lowest ≤ 4.6% products. linear regression model suggested product decreased significantly after adjustment highest reduction rate (NIR band) (red OLI–MSI-A OLI–MSI-B comparison, respectively. Further, this discussed use (i) time series total suspended solid concentrations (TSS) waters; (ii) floating algae area comparison; (iii) tracking changes (FA). Time analysis TSS seasonal variation well-captured by sensors. bloom revealed however, increases as overpasses increases. Furthermore, FA two months thin algal slicks (width < 500 can be detected an adequate spatial resolution MSI.