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INSTAAR seminar: Erika Johnson - Remote sensing of ocean waves and currents

Monday, March 29, 2021, 12:00PM - 1:00PM


Erika Johnson

Naval Research Lab


All are welcome to this virtual talk--if you'd like to attend, please email for the Zoom link and password.


Accurate quantification of waves and currents are essential in characterizing the overall hydrodynamics of the upper ocean. Within the oceanographic community, there is a growing desire to measure ocean waves and currents at higher spatial and temporal resolution than currently possible with in situ instruments. Remote methods of measuring waves and currents can be performed at high spatial and temporal resolution and their potential for remotely measuring turbulence is explored. In this presentation a two-dimensional power spectral density technique (2D PSD), which is based on calculating the cross-spectrum between two images is developed and compared with the established 3D PSD technique. In contrast to the 3D PSD technique, the 2D PSD algorithm is capable of accurately determining near surface flows from fewer images and to deeper depths. The 2D PSD technique is also capable of determining velocity time series and spectra, thereby facilitating remote measurements of turbulence. Results are presented from imagery collected from an unmanned aerial vehicle over the Gulf of Mexico and satellite imagery from a number of different locations.