Friday 10 Nov 2017: Turbulence and intermittency in the ocean winds seen by ASCAT and QuikSCAT
Greg King - University of Lisbon
In this seminar I will describe recent work carried out with colleagues at KNMI (Netherlands), ICM-CSIC (Barcelona), and NUIST (Nanjing) on characteristics of mesoscale turbulence (10 - 1000 km) and intermittency in the ocean winds derived from the ASCAT and QuikSCAT scatterometers. The study areas investigated were the Tropical Pacific, Tropical Atlantic and the Kuroshio Extension (east of Japan).
The turbulence was quantified using structure functions (moments of PDFs of velocity increments), and a new statistic called spatial variance that is an improvement over the second-order structure function (and the spectrum) in the characterization of the amplitude and scaling of turbulent kinetic energy.
Signatures of intermittency were observed in the statistics for the ITCZ and in the Kuroshio Extension, where skewnesses attained large negative values between -4 and -1 at scales between 50 and 500 km.