A Fast Biophysical Towed Profiler: the EcoCTD

As ocean processes at submeso-scales become increasingly studied, a need for in-situ measurements collected over spatio-temporal scales O(10 km) and O(hours) is rapidly emerging, posing significant observational challenges. We propose to address these challenges by underway sampling. We recently developed a towed profiler called the EcoCTD, capable of concurrently measuring both hydrographic and bio-optical properties such as oxygen, chlorophyll fluorescence, and optical backscatter. The EcoCTD presents an attractive alternative to currently used towed platforms due to its light footprint, versatility in the field, and ease of deployment and recovery without cranes or heavy-duty winches. We demonstrate its use for gathering high-quality data at submesoscale spatio-temporal resolution. A dataset of bio-optical and hydrographic properties, collected with the EcoCTD during field trials in 2018, highlights its scientific potential for the study of physical-biological interactions at submeso-scales.