A Study of the hydrographic conditions in the Adriatic Sea from numerical modelling and direct observations (2000–2008)

Abstract. The inter-annual variability of Adriatic Sea hydrographic characteristics is investigated by means of numerical simulation and direct observation. The period investigated runs from the beginning of 2000 to the end of 2008. The model used to carry out the simulation is derived from the primitive equation component of the Adriatic Forecasting System (AFS). The model is based on the Princeton Ocean Model (POM) adapted in order to reproduce the features of the Adriatic. Both numerical findings and observations agree in depicting a strong inter-annual variability in the entire Adriatic Sea and its sub-basins. The dense water formation process has been found to be intermittent. In addition to inter-annual variability, a long-scale signal has been observed in the salinity content of the basin as a consequence of a prolonged period of reduced Po river runoff and high evaporation rates. As a result, the temperature and salinity of the northern Adriatic dense water vary considerably between the beginning and the end of the period investigated.

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A study of the hydrographic conditions in the Adriatic Sea from numerical modelling and direct observations (2000–2008)

Ocean Science ◽

10.5194/os-7-549-2011 ◽

2011 ◽

Vol 7 (5) ◽

pp. 549-567 ◽

Cited By ~ 26

Author(s):

P. Oddo ◽

A. Guarnieri

Keyword(s):

Adriatic Sea ◽

Ocean Model ◽

Po River ◽

Northern Adriatic ◽

Dense Water ◽

Annual Variability ◽

Direct Observations ◽

Hydrographic Conditions ◽

Dense Water Formation ◽

Forecasting System

Abstract. The inter-annual variability of Adriatic Sea hydrographic characteristics is investigated by means of numerical simulation and direct observation. The period under investigation runs from the beginning of 2000 to the end of 2008. The model used to carry out the simulation is derived from the primitive equation component of the Adriatic Forecasting System (AFS). The model is based on the Princeton Ocean Model (POM) adapted in order to reproduce the features of the Adriatic. Both numerical findings and observations agree in depicting a strong inter-annual variability in the entire Adriatic Sea and its sub-basins. Nevertheless, two model deficiencies are identified: an excessive vertical/horizontal mixing and an inaccurate representation of the thermohaline properties of the entering Mediterranean Waters. The dense water formation process has been found to be intermittent. In addition to inter-annual variability, a long-scale signal has been observed in the salinity content of the basin as a consequence of a prolonged period of reduced Po river runoff and high evaporation rates. As a result, the temperature and salinity of the northern Adriatic dense water vary considerably between the beginning and the end of the period investigated.

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The Adriatic Sea modelling system: a nested approach

Annales Geophysicae ◽

10.5194/angeo-21-345-2003 ◽

2003 ◽

Vol 21 (1) ◽

pp. 345-364 ◽

Cited By ~ 93

Author(s):

M. Zavatarelli ◽

N. Pinardi

Keyword(s):

General Circulation ◽

Adriatic Sea ◽

Numerical Models ◽

Pilot Project ◽

Northern Adriatic ◽

Dense Water Formation ◽

Main Circulation ◽

Forecasting System ◽

Modelling System ◽

Circulation Characteristics

Abstract. A modelling system for the Adriatic Sea has been built within the framework of the Mediterranean Forecasting System Pilot Project. The modelling system consists of a hierarchy of three numerical models (whole Mediterranean Sea, whole Adriatic Sea, Northern Adriatic Basin) coupled among each other by simple one-way, off-line nesting techniques, to downscale the larger scale flow field to highly resolved coastal scale fields. Numerical simulations have been carried out under climatological surface forcing. Simulations were aimed to assess the effectiveness of the nesting techniques and the skill of the system to reproduce known features of the Adriatic Sea circulation phenomenology (main circulation features, dense water formation,flow at the Otranto Strait and coastal circulation characteristics over the northern Adriatic shelf), in view of the pre-operational use of the modelling system. This paper describes the modelling system setup, and discusses the simulation results for the whole Adriatic Sea and its northern basin, comparing the simulations with the observed climatological circulation characteristics. Results obtained with the northern Adriatic model are also compared with the corresponding simulations obtained with the coarser resolution Adriatic model. Key words. Oceanography: general (continental shelf processes; numerical modelling) – Oceanography: physical (general circulation)

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Numerical modelling of sediment transport in the Adriatic Sea

Ocean Science Discussions ◽

10.5194/osd-11-1391-2014 ◽

2014 ◽

Vol 11 (3) ◽

pp. 1391-1433 ◽

Cited By ~ 1

Author(s):

A. Guarnieri ◽

A. J. Souza ◽

N. Pinardi ◽

P. Traykovski

Keyword(s):

Sediment Transport ◽

Adriatic Sea ◽

Transport Model ◽

Data Availability ◽

Western Coast ◽

Po River ◽

Northern Adriatic ◽

Coastal Belt ◽

Italian Coasts ◽

The Impact

Abstract. A new sediment transport model, considering currents, tides and waves is presented for the Adriatic Sea basin. The simulations concentrate on the winter of 2002–2003 because of field data availability and interesting intermittent processes occurrence. A process oriented analysis is performed to investigate the impact that Sirocco and Bora wind regimes have on sediment transport. The comparisons of the simulations with the observed data show that the model is capable to capture the main dynamics of sediment transport along the Italian coasts and the sediment concentration within the water column. This latter can reach values up to several g L−1, especially within the first centimetres above the bottom. The sediments are transported mainly southwards along the Italian coasts, consistently with the known literature results, except during Sirocco wind events, which can be responsible for reversing the coastal circulation in the northern area of the basin, and consequently the sediment transport. The resuspension of sediments is also related to the specific wave regimes induced by Bora and Sirocco, the former inducing resuspension events near the coasts while the latter causing a more diffused resuspension regime in the Northern Adriatic basin. Beside the realistic representation of short timescales resuspension/deposition events due to storms, the model was also used to investigate persistent erosion or deposition areas in the Adriatic Sea. Two main depocenters were identified: one, very pronounced, in the surroundings of the Po river delta, and another one a few kilometres off the coast in front of the Ancona promontory. A third region of accumulation, even if less intense, was found to be offshore the southernmost limit of the Gargano region. On the contrary the whole western coast within a distance of a few kilometres from the shore was found to be subject to prevailing erosion. The comparison with observed accumulation and erosion data shows that the model captures well the main depocenters in the domain and the erosion within the very coastal belt of the western side of the basin, but seems to be too erosive in a few areas, in particular those where the contribution of sediment inflow to the sea of some minor but intermittently important rivers is not considered in a realistic way as input to the model.

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Seasonal and Interannual Trends of Oceanographic Parameters over 40 Years in the Northern Adriatic Sea in Relation to Nutrient Loadings Using the EMODnet Chemistry Data Portal

Water ◽

10.3390/w12082280 ◽

2020 ◽

Vol 12 (8) ◽

pp. 2280 ◽

Cited By ~ 1

Author(s):

Federica Grilli ◽

Stefano Accoroni ◽

Francesco Acri ◽

Fabrizio Bernardi Aubry ◽

Caterina Bergami ◽

...

Keyword(s):

Climate Changes ◽

Management Practices ◽

Adriatic Sea ◽

Nutrient Concentrations ◽

Data Series ◽

Mean Flow ◽

Northern Adriatic Sea ◽

Po River ◽

Northern Adriatic

Long-term data series (1971–2015) of physical and biogeochemical parameters were analyzed in order to assess trends and variability of oceanographic conditions in the northern Adriatic Sea (NAS), a mid-latitude shallow continental shelf strongly impacted by river discharges, human activities and climate changes. Interpolation maps and statistical models were applied to investigate seasonal and spatial variability, as well as decadal trends of temperature, salinity, chlorophyll-a and nutrients. This analysis shows that sea surface temperature increased by +0.36% year−1 over four decades. Annual mean flow of the Po River markedly changed due to the occurrence of periods of persistent drought, whereas the frequency of flow rates higher than 3000 m3 s−1 decreased between 2006 and 2015. Moreover, we observed a long-term decrease in surface phosphate concentrations in Po River water (−1.34% year−1) and in seawater (in summer −2.56% year−1) coupled, however, to a significant increase in nitrate concentration in seawater (+3.80% year−1) in almost all seasons. These changes indicate that the nutrient concentrations in the NAS have been largely modulated, in the last forty years, by the evolution of environmental management practices and of the runoff. This implies that further alteration of the marine environment must be expected as a consequence of the climate changes.

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The improvements of the ships of opportunity program in MFS-TEP

Ocean Science ◽

10.5194/os-3-245-2007 ◽

2007 ◽

Vol 3 (2) ◽

pp. 245-258 ◽

Cited By ~ 16

Author(s):

G. M. R. Manzella ◽

F. Reseghetti ◽

G. Coppini ◽

M. Borghini ◽

A. Cruzado ◽

...

Keyword(s):

Mediterranean Sea ◽

Pilot Project ◽

Quality Data ◽

Dense Water ◽

Short Period ◽

Water Formation ◽

Dense Water Formation ◽

Forecasting System ◽

Opportunity Program ◽

The Mediterranean

Abstract. The Ships Of Opportunity Program in the Mediterranean Sea was established at the end of 1999, in the framework of the Mediterranean Forecasting System – Pilot Project (MFS-PP). Many improvements have been made in data collection, transmission and management. Calibration of selected XBTs and a comparison of XBTs vs. CTDs during some research cruises have assured the quality of the data. Transmission now allows receiving data in full resolution by using GSM or satellite telecommunication services; management is offering access to high quality data and view services. The effects of technological and methodological improvements in the observing system are assessed in terms of capability to represent the most important circulation features. The improved methodologies have been tested during the Mediterranean Forecasting System – Toward Environmental Prediction (MFS-TEP) – Targeted Operational Period (MFS-TOP), lasting from September 2004 to February 2005. In spite of the short period of measurements, several important aspects of the Mediterranean Sea circulation have been verified, such as eddies and gyres in the various sub-basins, and dense water formation processes in some of them (vertical homogeneous profiles of about 13°C down to ~800 m in the Provençal, and of about 14.9°C down to ~300 m in the Levantine have allowed defining an index of dense water formation).

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Modelling Interannual Changes in Dense Water Formation on the Northern Adriatic Shelf

Pageoph Topical Volumes - Meteorology and Climatology of the Mediterranean and Black Seas ◽

10.1007/978-3-030-11958-4_21 ◽

2019 ◽

pp. 345-361

Author(s):

Hrvoje Mihanović ◽

Ivica Janeković ◽

Ivica Vilibić ◽

Vedrana Kovačević ◽

Manuel Bensi

Keyword(s):

Northern Adriatic ◽

Dense Water ◽

Water Formation ◽

Dense Water Formation

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Carbonate System and Acidification of the Adriatic Sea

10.5194/egusphere-egu2020-10977 ◽

2020 ◽

Author(s):

Valentina Turk ◽

Nina Bednarsek ◽

Jadran Faganeli ◽

Blaženka Gasparovic ◽

Michele Giani ◽

...

Keyword(s):

Mediterranean Sea ◽

Adriatic Sea ◽

Microbial Community Composition ◽

Aegean Sea ◽

Total Alkalinity ◽

The Black Sea ◽

Po River ◽

Saturation State ◽

Northern Adriatic ◽

The Mediterranean

Although the marginal seas represent only 7% of the total ocean area, the CO2 fluxes are intensive and important for the carbon budget, exposing to an intense process of anthropogenic ocean acidification (OA). A decline in pH, especially in the estuarine waters, results also from the eutrophication-induced acidification. The Adriatic Sea is currently a CO2 sink with an annual flux of approximately -1.2 to -3 mol C m-2 yr-1 which is twice as low compared to the net sink rates in the NW Mediterranean (-4 to -5 mol C m-2 yr-1). Based on the comparison of two winter cruises carried out in in the 25-year interval between 1983 and 2008, acidification rate of 0.003 pHT units yr&#8722;1 was estimated in the northern Adriatic which is similar to the Mediterranean open waters (with recent estimations of &#8722;0.0028 &#177; 0.0003 units pHT yr&#8722;1) and the surface coastal waters (-0.003 &#177; 0.001 and -0.0044 &#177; 0.00006 pHT units yr&#8722;1). The computed Revelle factor for the Adriatic Sea, with the value of about 10, indicates that the buffer capacity is rather high and that the waters should not be particularly exposed to acidification. Total alkalinity (TA) in the Adriatic (2.6-2.7 mM) is in the upper range of TA measured in the Mediterranean Sea because riverine inputs transport carbonates dissolved from the Alpine dolomites and karstic watersheds. The Adriatic Sea is the second sub-basin (319 Gmol yr-1), following the Aegean Sea (which receives the TA contribution from the Black Sea), that contribute to the riverine TA discharges into the Mediterranean Sea. About 60% of the TA inflow into the Adriatic Sea is attributed to the Po river discharge with TA of ~3 mM and TA decreases with increasing salinity. Saturation state indicates that the waters of the Adriatic are supersaturated with respect to calcite (&#937;Ca) and aragonite (&#937;Ar) throughout the year. However, saturation states are considerably lower in the bottom water layers, due to the prevalence of benthic remineralization processes in the stratification period. The seasonal changes of the chemical and environmental conditions and relatively small size of the Adriatic Sea area the microbial community composition, function (growth, enzymatic activity) and carbon and nitrogen biogeochemical cycles. Significant effects on calcifying organisms and phytoplankton are expected while the effects of possible OA on microbially-driven processes are not known yet.

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