Sein D.V., Dvornikov A.Yu., Martyanov S.D., Cabos W., Ryabchenko V.A., Gröger M., Mishra A.K.,
Kumar P., Gorchakov V. A.
Two experiments with a regional Earth System Model (ESM) are performed. We discovered that in a simulation where light attenuation is calculated taking into account the water temperature–phytoplankton feedback the average sea surface temperature (SST) is lower over most of the tropical Indian ocean in comparison with the reference experiment in which a constant light attenuation coefficient equal to 0.06 m‐1 , typical in global ESM runs, is used. We also find that the strongest differences (more than 1 °C) in SST occur in the summer period and a cooling of subsurface layers and a rise of the thermocline are noted in the experiment with the above feedback. Thus, including the full water temperature–phytoplankton feedback with corresponding light attenuation coefficient generally lowers the SST and water temperature in subsurface layers of the Indian ocean, with strong implications for the ocean-atmosphere coupling and, therefore for the simulated regional climate.