Carbonate Characteristics of the Gulf of Anadyr Waters

Abstract

The first field data describing the dynamics of the carbonate system, the aragonite saturation state, and CO₂ fluxes between the ocean and the atmosphere in the Gulf of Anadyr in the late autumn season are presented. It was established that during this period the gulf waters absorbed carbon dioxide from the atmosphere at a rate of –22.5 mmol m^–2 day^–1, which determined the “classical” mechanism of seawater acidification due to uptake of excess atmospheric CO₂. In general, surface waters of the gulf were supersaturated with respect to aragonite. The exception was the highly dynamic region of Anadyr Strait, where the vertical distribution of the investigated parameters was homogeneous, the surface waters were close to equilibrium with respect to aragonite, and the CO₂ flux was directed to the atmosphere. The bottom waters of the gulf, in contrast, were characterized by significant seasonal corrosivity due to remineralization of organic matter. It was shown that, during the late fall, relatively salty and acidic, quasi-equilibrium with respect to aragonite, and oxygen-depleted waters with high concentrations of nutrients and CO₂ enter into the Chirikov Basin and further to the Arctic Ocean with Navarin Current.