The impacts of interior ocean mixing on preformed property, remineralization ratio, and carbonate mineral cycling estimates

Brendan Carter, NOAA Pacific Marine Environmental Laboratory, Seattle, WA, United States, Siv Lauvset, Uni Research, Uni Climate, Bergen, Norway, Richard A Feely, NOAA PMEL, Seattle, WA, United States, Are Olsen, University of Bergen, Geophysical Institute, Bergen, Norway, Timothy J DeVries, University of California, Santa Barabara, Earth Research Institute and Department of Geography, Santa Barabara, United States and Rolf E Sonnerup, University of Washington, Joint Institute for the Study of the Atmosphere and Ocean, Seattle, WA, United States
Interior ocean mixing has been invoked to challenge some of the most influential recent scientific findings based on marine biogeochemical measurements. We revisit several of these topics, estimating preformed phosphate, nitrate, dissolved oxygen, silicate, and alkalinity by combining three distinct reconstructions of interior ocean ventilation pathways with algorithm-based estimates of sub-mixed layer properties. The resulting apparent property accumulations show remineralization ratios between nitrate and phosphate vary significantly between the subtropics and the subpolar regions of the ocean interior, that the most frequently used remineralization ratio estimates may be overestimating both RN:P and R-O2:P, that apparent oxygen utilization can significantly and inconsistently overestimate the net oxygen consumption that has occurred since water mass formation, and that a significant quantity (48%) of the total alkalinity accumulated from carbonate mineral dissolution is found in seawater that is super-saturated with respect to the aragonite mineral form of calcium carbonate.