On Sunday, we had the first day of IOP1 operations near Pt Sal. The Sally Ann and RV Sounder joined forces around the headland. It was a beautiful day at the point as it almost always is. The Pt itself was intermittently shrouded by marine fog, below is a view from the bay south of the point.
The drifters were “Davis” style drifters – see photo below, and are based on drifter designs from the 1980s. The update here is that the drifter tracking uses “spot” technology to get a GPS fix every 2-3 minutes. This data is then beamed back to Matt’s cell phone so that we can see where they are at all times. This realtime tracking makes drifter releases in wild settings such as Pt Sal feasible. We can grab them before they run aground.
We deployed a sequence of 27 drifters to the north Pt Sal. Drifters were released in 3 clusters of 9 drifters making the shape of a cross. Jim Thomson placed two SWIFT drifters in the center of each drifter grouping. We allowed the drifters to roam for about 4 hours while we surveyed with ADCP and CTD along w/ the RV Sounder. Below are the drifter trajectories on top of the bathymetry contours. Each cross pattern went offshore at first and then onshore. Most crosses went south and rotated (see the red and yellow/green) indicating the drifters were embedded in an eddy. This drifter release pattern was repeated again today (11-Sept).