5:15 PM - 6:30 PM
[ACG29-P08] Late-winter glider observation of upper ocean responses to weather disturbances in the western subtropical North Pacific
Keywords:ocean glider, mixed layer
The ocean glider is a buoyancy driven autonomous underwater vehicle which moves both horizontally and vertically in a sawtooth trajectory through the water toward a specified waypoint. The glider enables us to observe the remote ocean at relatively low cost and at high resolution both in space and time. Using the Slocum glider (manufactured by Teledyne Webb Research), the Meteorological Research Institute (MRI) has conducted hydrographic and biogeochemical observations in the western subtropical North Pacific around the Ogasawara Islands in winter 2020. The glider equipped with CTD, oxygen (RINKO II), and bio-optical (ECO FLBBCD) sensors is capable of monitoring water column down to 1,000m depth. After its deployment on March 3, 2020, the glider swam back and forth for 9 days to do semi-stationary observation at around its deployment location (145E, 30N). During this semi-stationary observation, the glider was set to dive down to 400 m depth to collect high temporal frequency data of the near-surface layer of the ocean. During the 9-day period, total of 150 ascending and descending profiles (more than 15 profiles every day) were obtained. This high temporal frequency data allows us to investigate upper ocean responses to weather disturbances. The observed mixed layer depth and mixed-layer properties as well as near-surface chlorophyll show large temporal variability, which is apparently associated with passages of low-pressure systems and/or weather fronts.