Research Spotlight: Measuring oceanic uptake of anthropogenic carbon

Abstract

As anthropogenic emissions of carbon dioxide increase, contributing to global climate change, it is important to understand how much carbon the ocean absorbs.Watanabe et al. present a time series of observations of the vertical distributions of oceanic anthropogenic carbon in the North Pacific subpolar region near the Sea of Okhotsk from 1999 to 2006. The authors compared two methods of measuring the rate of oceanic uptake of anthropogenic carbon, analyzed the sources of error in each method, and determined that the two methods agreed reasonably well. Their results show that the rate of oceanic uptake of anthropogenic carbon has increased recently and, in fact, is about 1.2 times higher than expected. They attribute this difference to an increase in the strength of ocean stratification and to a recent increase in alkalinity in the Sea of Okhotsk. (Journal of Geophysical Research‐Oceans, doi:10.1029/2010JC006199, 2011)