The inherent optical properties (IOPs) of Polar Waters (PW) exiting the Arctic Ocean in the East Greenland Current (EGC) and of the inflowing Atlantic waters (AW) in the West Spitsbergen Current (WSC) were studied in late summer when surface freshening due to sea‐ice melt was widespread. The absorption and attenuation coefficients in PW were significantly higher than previous observations from the western Arctic. High concentrations of colored dissolved organic matter (CDOM) resulted in 50–60% more heat deposition in the upper meters relative to clearest natural waters. This demonstrates the influence of terrigenous organic material inputs on the optical properties of waters in the Eurasian basin. Sea‐ice melt in CDOM‐rich PW decreased CDOM absorption, but an increase in scattering nearly compensated for lower absorption, and total attenuation was nearly identical in the sea‐ice meltwater layer. This suggests a source of scattering material associated with sea‐ice melt, relative to the PW. In the AW, melting sea‐ice forms a stratified surface layer with lower absorption and attenuation, than well‐mixed AW waters in late summer. It is likely that phytoplankton in the surface layer influenced by sea‐ice melt are nutrient limited. The presence of a more transparent surface layer changes the vertical radiant heat absorption profile to greater depths in late summer both in EGC and WSC waters, shifting accumulation of solar heat to greater depths and thus this heat is not directly available for ice melt during periods of stratification.
25Optical properties of Chromophoric (CDOM) concentrations in the study region, and the slope coefficient (S 300-600 ) shows some promise to 53 be used. 54Ocean Sci. Discuss., https://doi
Abstract. The fluorescence and absorption measurements of the samples collected from a surface microlayer (SML) and a subsurface layer (SS), at a depth of 1 m, were studied during three research cruises in the Baltic Sea along with hydrophysical studies and meteorological observations. Several absorption (E 2 : E 3 , S, S R ) and fluorescence (fluorescence intensities at Coble classified peaks: A, C, M, T the ratio (M + T ) / (A + C) , HIX (humification index)) indices of colored and fluorescent dissolved organic matter (CDOM and FDOM) helped to describe the changes in molecular size and weight as well as in composition of organic matter. The investigation allowed the assessment of a decrease in the contribution of two terrestrial components (A and C) with increasing salinity (∼ 1.64 and ∼ 1.89 % in the SML and ∼ 0.78 and ∼ 0.71 % in the SS, respectively) and an increase in components produced in situ (M and T ) with salinity (∼ 0.52 and ∼ 2.83 % in the SML and ∼ 0.98 and ∼ 1.87 % in the SS, respectively). Hence, a component T reveals the biggest relative changes along the transect from the Vistula River outlet to Gdansk Deep, in both the SML and SS, although an increase was higher in the SML than in the SS (∼ 18.5 and ∼ 12.3 %, respectively). The ratio E 2 : E 3 points to greater changes in the molecular weight of CDOM affected by a higher rate of photobleaching in the SML. The HIX index reflects a more advanced stage of humification and condensation processes in the SS. Finally, the results reveal a higher rate of degradation processes occurring in the SML than in the SS. Thus, the specific physical properties of surface active organic molecules (surfactants) may modify, in a specific way, the solar light spectrum entering the sea and a penetration depth of the solar radiation. Research on the influence of surfactants on the physical processes linked to the sea surface becomes an important task, especially in coastal waters and in the vicinity of the river mouths.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.