Ocean Visibility and Optics Lab

Project Manager

Lee Frey

Project Team

• Brian Ramos
• Edith Widder (ORCA)
• George LaBarca
• Kathy Russ
• Mike Young

Project Description

The BP Drifter is an autonomous, drifting, profiling instrument that can be used to find and measure bioluminescent thin-layers.  Based around a modified APEX profiling buoy, outfitted with a CTD and small Bathyphotometer, the BP Drifter can localize a bioluminescent thin-layer and drift within it, thus compensating for the “layer cake” effect caused by various differently moving water masses in the water column.  It accomplishes this by varying its buoyancy in order to position itself inside the thin-layer.  Its movements are then tracked from the surface via Ultra-Short Baseline (USBL) Sonar.  Periodic commands and data can be relayed underwater via Acoustic Modem, and at the surface via Iridium Satellite Modem.  If the drifter is lost, it can surface, take a GPS fix, and relay its position via satellite modem back to the ship.  Instructions can then be sent for a new mission, or the drifter can be recovered.  While inside the thin-layer, the composition and formation of the layer can be further studied with high-resolution instruments such as HIDEX.   This project was funded by the Office of Naval Research.