FIRe glider: Mapping in situ chlorophyll variable fluorescence with autonomous underwater gliders

Nutrient and light availability regulate phytoplankton physiology and photosynthesis in the ocean. These physiological processes are difficult to sample in time and space over physiologically and ecologically relevant scales using traditional shipboard techniques. Gliders are changing the nature of...

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Bibliographic Details
Published in:Limnology and Oceanography: Methods
Main Authors: Carvalho, Filipa, Gorbunov, Maxim Y., Oliver, Matthew J., Haskins, Christina, Aragon, David, Kohut, Josh T., Schofield, Oscar
Format: Article in Journal/Newspaper
Language:English
Published: 2020
Subjects:
Online Access:http://nora.nerc.ac.uk/id/eprint/528261/
https://nora.nerc.ac.uk/id/eprint/528261/1/lom3.10380.pdf
https://doi.org/10.1002/lom3.10380
Description
Summary:Nutrient and light availability regulate phytoplankton physiology and photosynthesis in the ocean. These physiological processes are difficult to sample in time and space over physiologically and ecologically relevant scales using traditional shipboard techniques. Gliders are changing the nature of data collection, by allowing a sustained presence at sea over regional scales, collecting data at resolution not possible using traditional techniques. The integration of a fluorescence induction and relaxation (FIRe) sensor in a Slocum glider allows autonomous high‐resolution and vertically‐resolved measurements of photosynthetic physiological variables together with oceanographic data. In situ measurements of variable fluorescence under ambient light allows a better understanding of the physical controls of primary production (PP). We demonstrate this capability in a laboratory setting and with several glider deployments in the Southern Ocean. Development of these approaches will allow for the in situ evaluation of phytoplankton light stress and photoacclimation mechanisms, as well as the role of vertical mixing in phytoplankton dynamics and the underlying physiology, especially in remote locations and for prolonged duration.