Using Remotely Sensed Sea Surface Salinity and Colored Detrital Matter to Characterize Freshened Surface Layers in the Kara and Laptev Seas during the Ice-Free Season

The overall volume of freshwater entering the Arctic Ocean has been growing as glaciers melt and river runoff increases. Since 1980, a 20% increase in observed system. As discharges Ob, Yenisei, Lena rivers are an important source Kara Laptev Seas, discharge might have significant impact on upper ocean circulation. fresh water mixes with forms large freshened surface layer (FSL), which carries high loads dissolved organic matter suspended into Ocean. Optically active material (e.g., phytoplankton detrital matter) spread out plumes, evident satellite data. Russian signatures Seas also recent SMOS Sea Surface Salinity (SSS) products. In this study, we compare new Arctic+ SSS products, produced at Barcelona Expert Center, Color absorption coefficient colored (CDM) for period 2011–2019. CDM found to be strongly negatively correlated regions influence, regression coefficients between −0.72 −0.91 studied period. Exploiting linear correlation, estimate back 1998 using two techniques: one assuming that relationship varies regionally river-influenced areas, another it does not. We use 22-year time-series reconstructed interannual variability extension FSL well their content. For 32 28 psu reference salinities, 26 24 isohalines boundaries, respectively. average is 2089–2611 km2, typical content 11.84–14.02 km3. slightly higher mean 2320–2686 km2 10.15–12.44 yearly FSL, computed from Optical data, (as expected) co-vary situ measurements Great Rivers Observatory database, demonstrating potential better monitor changes Eurasia understand system during ice-free season.