The Adriatic circulation is a key component to understand risks in several coastal activities (Fishing, transport, recreation) and to implement management and mitigation plans in this area separating the Balkan and the Italian peninsulas.
Discover how and for which benefits , the scientists of the Marine Biology Station (MBS) in Piran, part of the Slovenian National Institute of Biology (NIB) are working towards identifying and describing major patterns and trends of the Adriatic Sea circulation.
The Adriatic Sea separates the Balkan and Italian peninsulas. People living along these shores are all concerned by the fishing , transport and recreation activities.
Major rivers, such as the Po, end up in the Adriatic and many cities are located along its coastline.
Recent issues about the Venice floods and other related events have put the area in the spotlight regarding coastal zone management. As a consequence, the Adriatic circulation is now considered as an important component for understanding the risks and for implementing mitigation and management plans for the area.
Water circulation is very important to marine scientists as it holds information that is used for forecasting, identifying past and present patterns and trends and is a defining characteristic of the seas surrounding us. At the Marine Biology Station (MBS) in Piran, which is part of the Slovenian National Institute of Biology (NIB), scientists are working towards identifying and describing major patterns and trends of the Adriatic Sea circulation.
MyOcean2 services provide to scientists of MBS with a dataset of analysis or "past forecasts" in this area which benefitted to :
- studies of the Adriatic circulation patterns
- studies about accidents forecast and prevention of accidents (including Mercury pollution)
- studies on the effects of wind on the overall circulation
In their effort to describe the past and present circulation of the Adriatic Sea, the scientists of the Marine Biology station collaborated with the Faculty of Computer and Information Science of Ljubljana University to extract information (also known as data mining) from a large number of Lagrangian trajectories. Lagrangian trajectories take into account the three dimensional movement of water and allow scientists to distinguish water masses in terms or origin and destination.
The challenging part was to develop the data mining methods to take into account both the spatial and temporal dimension of the data in order to reveal the typical frequent patterns in circulation such as paths and gyres as shown in Figure 1.
The team of scientists used calculations of water movement speed from the Mediterranean Ocean Forecasting system (MFS) for the period 1999-2011 provided by MyOcean2. All the methods and algorithms developed by the team, have been published in peer reviewed scientific journals and are now available to any scientist working on water masses movements.
Environmental agencies, governmental authorities and monitoring bodies could be direct users of the data provided by this tremendous work. On the top of the scientific added-value, this work enables to provide real-time estimation of pollution loads and hotspots likely to be affected by weather patterns.
PREDICTING and PREVENTING ACCIDENTS
The MBS scientists are using MyOcean2 products on a daily basis to provide high resolution ocean state forecasts for the Adriatic Sea as shown in Figure 2.
These models are directly connected to pollution dispersion models. The quality of their forecasts is fundamental for proper immediate response of rescue operations in the Northern Adriatic in case of an oil spill or similar marine emergency.
Due to extensive marine traffic related to two major cargo ports in Koper and Trieste the possibility of such events is very real.
To improve forecasting capabilities, the MBS scientists have collaborated with the Italian National Institute of Oceanography and Experimental Geophysics (OGS) in a setup of high frequency (HF) surface current radars along the Slovenian and Italian coast. These common efforts suggest that HF radar current observations complement model simulations in regions of enhanced topographic variability while the model results complement radar observations in areas with poor radar coverage, and furthermore provide spatial and temporal continuity of ocean state forecasts.
Beside accident prevention and prediction, the models analyze dispersion of toxic Mercury in the Gulf of Trieste. As a consequence of Mercury mining in Idrija (the mine has been closed for years) hundreds of kilos of Mercury are estimated to enter the Gulf of Trieste each year through the Isonzo river. Numerical models for Mercury dispersion give researchers and decision makers a solid ground on which to build sensible environmental policies.
In theory, when the wind blows along the axis of the Adriatic basin, vertically integrated current (transport) should be windward in the shallow areas, close to the coastline, while the direction of the transport should oppose the wind in the areas where depth is larger than average cross-section depth.
An operational oceanographic model (NAPOM) is used to confirm this theory. NAPOM is an operational oceanographic model of Northern Adriatic, developed by MBS and based on the Princeton Ocean Model. It is nested into AFS (Adriatic Forecasting System), developed by INGV (Istituto Nazionale di Geofisica e Vulcanologia).
Scenarios with the two most prominent winds (bora and sirocco or burja and jugo) in the area were simulated, using operational weather forecast of Slovene ALADIN/SI meteorological model. Bora (NE) blows along the axis of Gulf of Trieste, while Sirocco (SE) blows along the axis of the Adriatic basin. A schematic of the study area and is shown in Figure 3.
NAPOM simulations qualitatively largely confirm the theory, allowing scientists to produce realistic predictions of wind-driven circulation.
Whatever the research domain of the Marine Biology Station scientists, always targeting citizen protection along the Adriatic Coastal area, MyOcean Reanalysis (Mediterranean Sea Physics Reanalysis 1999-2011) and Analysis data (Mediterranean Sea Physics Analysis and Forecast) are precious for their modeling work and efforts to decoding the Adriatic sea circulation.
More information: http://www.mbss.org/portal/index.php?lang=en
Slovenia, along the Adriatic Sea, at the North of Italy.
Scientists from the Marine Biology Station(MBS) part of the National Institute of Biology strive to describe the past and present circulation of the Adriatic Sea.
The coastal town of Piran, Slovenia. Credit: Matjaz Licer
Figure 1: Cycles and paths in the surface velocity fields of the MyOcean reanalysis (Mediterranean Sea Forecasting System 1999-2011): A) cyclonic cycles, B) anticyclonic cycles, C) paths and cycles in September 2000 and D) frequent cyclonic and anticyclonic cycles.
Figure 2: Non-tidal circulation in the Adriatic as calculated by the ADRIPOM ocean model (initialized and laterally forced by MyOcean2 Mediterranean model's circulation).
Another view of Piran, Slovenia. Credit: Matjaz Licer
Figure 3: NAPOM model domain in the northern Adriatic. The red line represents a cross-section of the northern Adriatic, the red dashed line represents a cross-section in the Gulf of Trieste. The ENE bora wind is parallel to the red dashed line. Rivers are represented as straight-line indentations in land.