Evolution of mean surface pH in relation to DIC and sea surface temperature for both the control experiment (solid black line) and climate change experiment (solid red line). The net climate change feedback is shown as the dashed black vector between the control and climate change experiments. Point A is the initial state in the year 1880 before industrialization. Point B is the pH state (~7.82) in the year 2100 if the ocean absorbed atmospheric CO2 under equilibrium proportions. Point C is the pH state (~7.93) in the year 2100 for the control experiment and is equivalent to an oceanic steady state solution. Point D is the pH state (~7.93) for the year 2100 under climate change, and includes feedbacks such as circulation, biological production and temperature.