Active Thermal Stereo Imaging of the Ocean Surface Turbulence during CASPER-West

A novel non-intrusive turbulence sensing technique has been employed to observe Upper Ocean turbulence from Research Platform FLIP during the CASPER-West field campaign. The technique employs a 100W CO₂ laser to draw and refresh custom thermal patterns on the skin layer of the ocean surface, which are then observed by two mid-wave infrared cameras in stereo mode. The imagery is then used to reconstruct 3D geometry and motion of the water surface. These high fidelity spatial and temporal ensembles of surface turbulence and roughness properties on 1 cm – 1 m scales were collected in a wide variety of weather conditions with wind speeds U₁₀ up to 18 m/s. This presentation will include details and trade-offs of this new methodology, discuss the reasoning behind a variety of sampled thermal patterns, and demonstrate some of the unique turbulence statistics obtained during the experiment.