Heavy Duty

Kristen setting the AWAC & SeaFET
(pH sensor) in place. 

The immense spatial nature of internal waves, stretching thousands of feet across different density layers below the ocean's surface, leads to their important role in the mixing of ocean waters. Here at Dongsha in the South China Sea, observing the water column as it flows from the ocean, over the reef, and into the lagoon, requires a baseline measurement of temperature and currents offshore of the reef. A few days ago we successfully installed ‘E1’, our dense 16 meter mooring that holds 7 temperature loggers spaced evenly between a temperature and pressure sensor at the top, and a MicroCAT (temperature + pressure + oxygen sensor) at the bottom, in the deep offshore section of the reef. Each temperature logger is 2 m apart, allowing us to observe the thermal stratification of the water column before it enters the lagoon. 

4 large buckets filled with concrete helped
weigh down the 'E1' mooring. 

We were also fortunate enough to have Tom and Kristen scuba down a platform that holds the AWAC, an acoustic surface tracking instrument that profiles currents and wave direction, and a pH meter to a depth of ~20 m. We already installed a similar platform in the shallower lagoonal side of the reef, which contains an ADCP (acoustic Doppler current profiler) and another MicroCAT. This hard work marks a significant portion of our efforts to characterize flow across the reef, and will make for some interesting data!





-Aryan Safaie
Graduate Student
Coastal Dynamics Lab, UCI