Processing and Analysis of Velocity and CTD Data from a Wirewalker Wave-Powered Profiler Experimental Deployment

We fitted a Wirewalker, wave-powered profiling instrument, platform with a Nortek Signature1000 Acoustic Doppler Current Profiler (ADCP) and an RBR conductivity-temperature-depth (CTD) profiler to obtain high-resolution velocity, gyroscopic, and water column measurements across a 100-m depth experimental deployment off the Florida shelf. Using pings of sound transmitted at a constant frequency to measure oncoming moving particles, the ADCP can translate the frequency shift from the returned signal into usable East-North-Up components velocity measurements and by using its built-in 3D compass it’s able to provide accurate measurements of pitch, roll, and heading. Here, we used the data of the ADCP during the Wirewalker’s up-casts and down-casts, averaged by depth bins at a 0.5m resolution, to test for the presence of a southward flowing undercurrent jet. Velocity averages were corrected for platform movement using gyroscopic measurements and plotted against depth. Preliminary analysis of our results shows no evidence for the presence of this undercurrent, although a realignment towards a horizontal mounting of the ADCP to reduce environmental noise and further work on the velocity corrections have been done to prepare for future deployments.