Classification of pCO2-DO Correlations of Seawater off Tomakomai

When evaluating the partial pressure of CO2 (pCO2) and the dissolved oxygen (DO) saturation, it is known that there is an approximate linear correlation between them. Tomakomai, Japan is known as the transition area of two currents]. Both warm water derived from Kuroshio Current and cold water derived from Oyashio Current into this area. The values of pCO2 can be different in these two waters. Thus, we thought that there may be more than one straight line. In this paper, we classified the pCO2 and DO saturation data and proposed appropriate correlations between them for approximation, using a temperature-salinity diagram.