First analysis of the jugo wind microscale properties

Jugo je karakterističan vjetar na Jadranskom moru koji puše iz smjera jugoistoka do juga. Razlikuju se ciklonalno i anticiklonalno jugo. Oni često uzrokuju visoke valove koji mogu ometati promet te u biometeorološkom smislu nepovoljno utjecati na neke ljude. Podaci korišteni u radu su mjereni na tornju blizu Masleničkog mosta frekvencijom uzrokovanja od 10 Hz. Promatrana epizoda juga trajala je ≈34 sata s početkom 02. listopada 2020. godine u 13:18 sati. Cilj ovog rada je odrediti po prvi puta mikroskalne karakteristike juga, TKE i njenu disipaciju ε. Određena je skala usrednjavanja turbulencije, a viskozna disipacija je procijenjena koristeći metodu inercijalne disipacije. Provjereno je teorijsko slaganje -5/3 pravca u log-log ovisnosti spektra o frekvenciji. Izračunata je empirijska skala duljine koja se može koristiti u numeričkim modelima za parametrizaciju. Provjereno je slaganje teorijske relacije odnosa TKE i ε. Pokazano je da se jugo dobro slaže s tom teorijskom relacijom.Jugo is a characteristic Southern or Southeastern wind at the Adriatic sea. There are cyclonic and anticyclonic jugo winds. They often cause high waves which can impact traffic and can also adversely affect some people in biometeorological meaning. The data used in this paper was obtained from the tower near the Maslenica bridge with the sampling frequency of 10 Hz. The observed episode of jugo wind lasted ≈34 hours starting October 2nd of 2020 at 1:18 pm. The goal of this study is to determine for the first time the microscale characteristics of the jugo wind, TKE and its dissipation rate ε. The turbulence averaging scale was determined and viscous dissipation was estimated using the inertial dissipation method. The theoretical agreement of the -5/3 slope in log-log dependence of the spectrum and frequency was tested. An empirical length scale which can be used in numerical model parametrization was calculated. The agreement of the theoretical relation between TKE and ε was checked. The jugo wind has shown to agree well with the theoretical relation