Using the forecasting circulation Princeton Ocean Model over the northern Adriatic Sea (NAPOM) two synoptic wind-driven situations of the circulation in the northern Adriatic were studied. In both situations the basin was driven by a relatively steady wind ()8 m/s) along and across the basin over three days. In the first situation (28–30 October 2008) the SSE southern jugo or scirocco wind blew along the basin, and in the second (19–21 March 2009), the ENE bora wind blew across the basin. Cyclonic turn was present in the first situation, while the cyclonic branch of a known double gyre circulation north of the strip of wind minima was evident in the second. We show that during the jugo the model does not confirm quantitatively the simple topographic control of a wind-driven circulation, suitable for elongated basins, while qualitatively the model meets expectations, with downwind transport in shallow areas close to shorelines and upwind transport in places with greater depths. During the bora wind, however, the wind-driven circulation in the Gulf of Trieste is well explained by this topographic control (82% of the flux through the transect).
COBISS.SI-ID: 2595663
From late January to mid-February 2012 the Gulf of Trieste (North Adriatic Sea) was affected by a severe winter weather event characterized by cold air and strong northeasterly wind (Bora). The atmospheric forcing caused large surface heat fluxes which produced remarkable effects on the gulf, particularly the production of a very cold and dense water mass. Temperatures as low as 4 °C were observed in the deepest part of the gulf, similar to that which was observed in winter 1929, which was probably the most severe winter in the region over more than a century. The density anomaly attained values up to 30.58 kg/m^3, even greater than in 1929. Surface heat fluxes were estimated using bulk formulas and the meteorological and marine observations available at three stations. Mean daily heat losses exceeded 1000 W/m^2.
COBISS.SI-ID: 2934607
The recent developments in pollutant measurement methods and techniques necessitate improvements in modelling approaches. The models used so far have been based on seasonally averaged data, which is insufficient for making short-term predictions. We have improved the existing modelling tools for pollutant transport and dispersion on three levels. We significantly refined the numerical grid; we used temporally and spatially non-uniform meteorological parameters for predicting pollutant dispersion and transformation processes; we used grid nesting in order to improve the open boundary condition. We worked on a typical contaminated site (The Gulf of Trieste), where mercury poses a significant environmental threat and where an oil-spill is a realistic possibility. By calculating evasion we improved the mass balance of mercury in the Gulf. We demonstrated that the spreading of river plumes under typical wind conditions is different than has so far been indicated by model simulations. We also simulated an oil-spill in real time. The improved modelling approaches and the upgraded models are now suitable for use with the state-of-the-art measurements technology and can represent an important contribution to the decision-making process.
COBISS.SI-ID: 6203745
In order to simultaneously simulate sediment resuspension caused by shipping and wind induced waves and currents, we have upgraded the sediment transport module of the PCFLOW3D model and used additional high-quality input data: (1) wave parameters were obtained using the SWAN model; and (2) bottom velocities due to shipping were calculated based on the Automatic Identification System data and added to the wind-induced bottom currents. The upgraded model enables short-term simulations of bottom shear stress and sediment resuspension due to combined effects of wind and navigation.
COBISS.SI-ID: 6604129
A comparison of modelling results computed by two sediment transport models is presented. The PCFLOW3D is z-level based, while the ECOMSED uses s-layer coordinates. Consequently, their bottom velocities differ slightly. Bottom shear-stress and sediment resuspension were calculated separately for currents, waves and combined forcing conditions. Different typical wind conditions were taken into account. Although both models use the same approach (van Rijn, 1993) to simulate bottom shear-stress, resuspension and sediment transport, some discrepancies in the results were noticeable. The shear-stress results of the two models are in relatively good qualitative agreement, while the agreements of resuspension and suspended sediment concentrations within the water column are somewhat poorer. Furthermore, in small areas such as the Koper Bay the open boundary condition can have a significant impact on hydrodynamic parameters and consequently on sediment transport. One-way nesting with a larger computational domain would be necessary.
COBISS.SI-ID: 5897057