Impacts of Increased Atmospheric CO2 on Ocean Chemistry and Ecosystems

Abstract

Ocean pH is a function of the seawater carbonate system, which is a function of both the influx of CO2 from the atmosphere and the resulting concentration of CO2 in the water (i.e. pCO2). Uptake of anthropogenic carbon dioxide from the atmosphere is reducing ocean pH; a phenomenon referred to as ocean acidification. It is estimated that there has been a decrease of 0.1 pH units in the surface waters of the world’s oceans since the start of the industrial revolution with a reduction of 0.3 – 0.5 forecast by 2100. There is growing concern over the potential consequences of ocean acidification for marine ecosystems and the services they provide for mankind. This project was aimed at enabling the capability and developing the expertise within Ireland to measure and quantify the flux of CO2 into (or out of) the ocean; to monitor seasonal trends in pCO2 and CO2 fluxes; to determine the current baseline state and variability of the carbonate system; and to evaluate the potential impact of future changes on ecosystems with the ultimate aim of contributing to more informed policy development.