Major role of particle fragmentation in regulating ocean CO2 sequestration – and other autonomous insights into the biological pump
A critical driver of the ocean carbon cycle is the downward flux of sinking organic particles, which acts to lower the atmospheric CO2 concentration. We have evidence that this carbon sink has varied strongly in the past, but significant gaps in our understanding currently prevent us from predicting how it might change in the future. The recent rapid growth of particle measurements from autonomous profilers represents a powerful and under-utilized new tool for uncovering the drivers of sinking carbon flux. In the near future, a global network of “Biogeochemical Argo” profiling floats should extend these insights to a global scale, and allow us to start to monitor multi-year trends. This talk will focus on how autonomous platforms are being used to yield new insights into downward carbon flux, including the recent finding that particle fragmentation plays a key role in regulating organic carbon flux to the ocean interior.