Impact of Transmission Scheme of Visible Solar Radiation on Temperature and Mixing in the Upper Water Column With Inputs for Transmission Derived From Ocean Color Remote Sensing

Abstract

AbstractThe penetration of visible solar radiation (VSR) in the upper ocean contributes to heating in the upper water column, and this process is modulated by constituents in water such as phytoplankton. Various schemes have been developed to propagate surface VSR to deeper depths, which are incorporated in ocean circulation models to study basin‐scale impacts on ocean and atmosphere by phytoplankton. However, none of these studies evaluated sensitivity of the schemes of VSR transmission to upper‐water dynamics, especially when the required input is derived from ocean color remote sensing. We used an idealized one‐dimensional (1‐D) Regional Ocean Modeling System (ROMS) to simulate profiles of upper water column temperature at six locations with different ocean color characteristics (containing different water constituents). We incorporated and tested four different schemes of VSR transmission: the default water‐type scheme within the ROMS, two schemes based on concentrations of chlorophyll (Chl), and one scheme based on water's inherent optical properties (IOPs). The results showed that, although using the same ocean color information and the same circulation model, the IOPs‐ and Chl‐based schemes resulted in very different vertical temperature and upper‐water mixing compared to those using the default scheme, with differences in sea surface temperature up to 1.5–2°C. These results highlight the importance of developing and incorporating more appropriate VSR transmission schemes into large‐scale ocean circulation simulations, where the inputs for the transmission are inherently estimates from ocean color—the actual measurement from satellite remote sensing.