Naslov
Modelling the trajectories of satellite – tracked drifters in the Adriatic during summertime bora event

Autori
Beg Paklar, Gordana ; Dadić, Vlado ; Koračin, Darko ; Orlić, Mirko ; Poulain, Pierre-Marie ; Vellore, Ramesh ; Vilibić, Ivica ; Žagar, Mark ; Žagar, Nedjeljka

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
EARTH: OUR CHANGING PLANET, Proceedings of IUGG XXIV General Assembly, IAMAS / Lucio Ubertini, Piergiorgio Manciola, Stefano Casadei - Perugia, 2007

ISBN
978-88-95852-25-4

Skup
IUGG XXIV General Assembly

Mjesto i datum
Perugia, Italija, 02.07.2007. - 13.07.2007

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
numerical modelling; air-sea interaction; bora

Sažetak
Satellite-tracked drifter data and meteorological wind measurements indicated summer bora event of 22 - 25 June 1995 as interesting from both meteorological and oceanographic point of view. The studied summer situation was controlled by a mesoscale atmospheric disturbance that imparts strong cyclonic vorticity to the wind field, with the orographic effect being of secondary importance. During the bora event currents of 70 cm s-1 were measured by drifter movements tracked along the western Adriatic coast. Drifter trajectories for the selected period were simulated by an oceanographic model forced by the outputs of two mesoscale meteorological models, ALADIN and MM5, and by river discharges. The atmospheric models provided realistic space- and time-varying atmospheric fields (wind, air temperature and humidity) with ca 10 km horizontal resolution by ALADIN and with 9 and 3 km by MM5. Several numerical experiments with different combinations of the three forcing agents – wind stress, river discharges and surface heat fluxes – were performed. Proper formulation of the drag coefficient was crucial for the correct simulations of the drifter trajectories, as its increased values do reproduce well the effects of the sea surface roughness and atmospheric stability to the surface ocean layer with respect to the observed drifter movements. Numerical experiments revealed that strong current along the western Adriatic coast resulted from a combined influence of the wind stress and river discharges. The importance of the baroclinic, buoyancy driven contribution to the current field was particularly pronounced in the periods with weak winds. At the same time, drifter movements in the open sea area in front of the eastern Istrian coast were the result of the wind stress acting solely.

Izvorni jezik
Engleski

Znanstvena područja
Geologija

POVEZANOST RADA