Measurement of dissolved inorganic carbon (DIC) for ocean acidification research

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Anthropogenic carbon dioxide emissions are being absorbed by the oceans, where the excess CO2 shifts the carbonate equilibrium and leads to ocean acidification. The expected doubling of atmospheric CO2 will lead to oceanic pH drops of 0.3 - 0.5 units over the course of this century. Such radical changes in ocean pH have not been seen for millions of years. The excess CO2 / lowered pH will have important effects on marine organisms, ranging from changes in development, growth, and survival. These organismal-level impacts will in turn translate to dramatic changes in marine populations, communities, and ecosystems.Although experimental work on ocean acidification is now underway, including in the laboratories of Drs. Harley and Brauner. However, this research is severely hampered by a lack of measurement accuracy. Readily available techniques for measuring dissolved CO2 are only accurate to a few hundred parts per million, which is clearly inadequate for precisely measuring a climate system which is expected to shift from 380 ppm today to between 540 and 970 ppm at the end of the century. Thus, even the best published research does not measure CO2 with sufficient accuracy, but instead relies on calculations based upon untested assumptions regarding gas saturation and organismal uptake.To enhance the accuracy of our ocean acidification experiments and thus gain an understanding of  the CO2 concentrations - and thus the climate change scenarios - that we are actually testing, we request a highly sensitive dissolved inorganic carbon (DIC) analyzer. In conjunction with existing pH electrodes and the requested computer, this system will allow us to measure CO2 with unprecedented but absolutely necessary accuracy. Only once such accuracy has been achieved can acidification experiments be translated into actual climatic predictions.