Spatiotemporal high-resolution mapping of biological production in the Southern Ocean

Abstract

The Southern Ocean is considered to play an important role in the global biogeochemical cycles of carbon and nutrients. It is still unclear how biological production there impacts climate change owing to the remarkable gap between the current and the ideal state of research. Here, we proposed a new concept of combining Neural Network based parameterization of dissolved inorganic carbon with Biogeochemical Argo floats, showing simultaneously spatiotemporal distributions of net community production and resupply of carbon from the deep ocean based on the dissolved inorganic carbon change. It indicated a total net community production of 4.1 ± 0.3 Pg-C year−1 over the Southern Ocean, which accounts for 45% of global annual oceanic carbon export and is 20% higher than the previous estimates. Furthermore, net community production in the Southern Ocean has decreased by 0.8% year−1 since the 2010s, indicating that it may be contributing as positive feedback to global warming.