Abstract:

The LASER drifter is a new surface drifter that is compact, cost-effective, and biodegradable. It accurately follows the current over the upper 0.60m, with very limited influence of the wind or waves. A series of experiments was carried out in the ASIST wind-wave flume to evaluate the water following capabilities of the drifter in the presence of strong winds and waves. The trajectories of the CODE drifter and the LASER drifter were compared during short deployments in the ocean. This dataset contains the drifter's velocity measured in the tank under different current, wind and waves conditions. It also contains the trajectories of the drifters in the ocean.

Suggested Citation:

Guillaume Novelli, Cédric M. Guigand, Tamay M. Özgökmen. 2017. Lagrangian Submesoscale Experiment (LASER) drifter calibration. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/N7VH5KWX

Publications:

Novelli, G., Guigand, C. M., Cousin, C., Ryan, E. H., Laxague, N. J. M., Dai, H., … Özgökmen, T. M. (2017). A Biodegradable Surface Drifter for Ocean Sampling on a Massive Scale. Journal of Atmospheric and Oceanic Technology, 34(11), 2509–2532. doi:10.1175/jtech-d-17-0055.1

Purpose:

The purpose of this dataset is to quantify the water following capabilities of the novel surface drifter design.

Data Parameters and Units:

drifter's trajectories (positions and UTC time), velocity profiles (m/s), date time (MM/DD/YYYY HH:MM), wind speed (m/s), direction (the direction the wind is coming from in degrees clockwise from true N), gusts (m/s), air temperature (deg C), barometric pressure (hectopascal), average wind direction (towards) each deployment, average wind speed each deployment, deployment number

Methods:

For a variety of controlled flow, we compare the drifter's velocity to the measured (by PIV and dye-tracking) horizontal Lagrangian velocity depth-averaged over the drifter's draft. In the field we compare the trajectories of the LASER drifter and the CODE drifter.

Instruments:

We used the Air-Sea Interaction Saltwater Tank (ASIST) at the University of Miami's SUSTAIN (Surge-Structure Atmosphere Interaction) facility, which offers the possibility to control the flow via a water-pump, a paddle wave-maker and a wind generator. The acrylic flume is 15 meters long, with 1 m by 1 m cross-section, and a mean water depth set to 0.43 m. A permeable wave-absorbing sloped beach is installed at the downwind end. The sampling window is a 1.60 m long section of the flume, located at equal distance ($\sim$ 6 m) from the inlet and the outlet of the flume to minimize any boundary effects. The wind speed in the tunnel was monitored by a sonic anemometer located in the sampling window, 0.285 m above the mean water level. Two wave-gauges (partially submerged conductivity probes) were installed at two different locations in the sampling window to make sure the wave field was homogeneous in the measurement area. Subsurface Eulerian current profiles were measured by Particle Image Velocimetry (PIV). Food-dye droplets, released just above the free surface, were filmed at 30 frame-per-second by a camera mounted on the side of the tank and looking slightly upwards.

Individual Files: