Observing a Western Mediterranean overturn event with a Navis BGC autonomous profiling float

摘要

If billions of phytoplankton fall in the ocean and no one observes it, does it still result in a net sequestration of carbon? In the case of a dramatic deepwater formation event off the Gulf of Lyon in the winter of 2013, the 'fall' was seen by an autonomous float equipped with the biogeochemical sensors needed to record the event Profiling floats have proven to be a stalwart technology economically generating robust basin scale data sets of temperature and salinity that have significantly increased our fundamental understanding of the ocean. The Navis BGC floats take advantage of advances in float technology and sensor miniaturisation (Barnard and Mitchell, 2013) to expand the capability of the float technology to carry a broad suite of biogeochemcal sensors. With sensors for dissolved oxygen, phytoplankton pigments (chlorophyll), particle mass concentration and particulate organic carbon (backscattering and beam attenuation), dissolved organic matter (fDOM), nitrate and pH, the Navis float platform can be used to autonomously monitor the major parameters of biogeochemical processes.