Two biogeochemical-Argo floats (BGC-Argo) will be deployed during the SOLACE voyage. These autonomous platforms (PROVBIO, manufactured by NKE) will collect year-round and depth-resolved observations of five essential biogeochemical variables: chlorophyll a, suspended particles, oxygen, nitrate and downwelling irradiance. In addition, the floats will carry the newly developed miniaturised Underwater Vision Profiler (UVP6) which captures images that are automatically analysed to provide the size distribution of non-living particles and zooplankton in the 100 μm to 2 cm size range. The two-way Iridium communication implemented on the floats will allow to adapt in near real time the sampling strategy to best characterised the functioning of the Biological Carbon Pump over complete annual cycles in a variety of environments. In particular, we expect the floats to reveal the seasonality of multiple carbon export pathways, including the gravitational pump and particle injection pumps (e.g. the mixed layer pump, eddy subduction pump and vertical migration pump).
The RESPIRE (Respiration of Sinking Particles In the subsuRface ocEan) is a particle interceptor/incubator that allows to non-intrusively intercept settling particles at fixed depths, and immediately incubate them within this device at the in situ pressure and temperature. RESPIRE provides rates of remineralization by particle-attached bacteria based on an oxygen consumption time-series (Boyd et al. 2015; Bressac et al. 2019).
Boyd, P.W., et al. (2015) RESPIRE: An in situ particle interceptor to conduct particle remineralization and microbial dynamics studies in the oceans’ Twilight Zone. Limnology and Oceanography: Methods. doi:10.1002/lom3.10043.
Bressac, M., et al. (2019) Resupply of mesopelagic dissolved iron controlled by particulate iron composition. Nature Geoscience. doi:10.1038/s41561-019-0476-6.