A High-Resolution Numerical Model of the North Aegean Sea Aimed at Climatological Studies

A new, high-resolution model for the northern part of the Aegean Sea, aimed primarily at climatological research (relaxation and data assimilation-free climate simulations), is hereby presented, along with the results of a 28-year-long simulation covering the period from 1986 to 2013. The model applied is the Regional Ocean Modelling System (ROMS). A significant improvement over previous models of the Aegean introduced in this work is the replacement of parameterizations of the Dardanelles exchange by a fully three-dimensional simulation of the flow in the Strait. The incorporation of part of the Marmara Sea in the model domain enables the interaction with other regional climate simulations, thus allowing climatic variability of the exchange of the Mediterranean and Black Seas. An extensive validation is carried out comparing the model output with all the available observations from several different platforms, i.e., satellite sea surface temperature and height, T/S profiles from R/V ships, and HF radar surface currents velocity. We focus on the model’s ability to reproduce, to some extent, the distinct thermohaline features and circulation patterns that characterize this specific area of the Mediterranean Sea. Our findings, after comparing simulation results with all the available observations, revealed the model’s sufficiency to simulate very adequately the complex hydrology of the North Aegean Sea, and the model’s ability to reproduce incidents of deep-water formation that took place in the region in previous decades during the Eastern Mediterranean Transient (EMT).

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New Fisheries-related data from the Mediterranean Sea (April 2014)

Mediterranean Marine Science ◽

10.12681/mms.738 ◽

2014 ◽

Vol 15 (1) ◽

pp. 213 ◽

Cited By ~ 8

Author(s):

K. STERGIOU ◽

D.C. BOBORI ◽

F.G. EKMEKÇİ ◽

M. GÖKOĞLU ◽

P.K. KARACHLE ◽

...

Keyword(s):

Mediterranean Sea ◽

Eastern Mediterranean ◽

Feeding Habits ◽

Aegean Sea ◽

Northern Greece ◽

Related Data ◽

The North ◽

North Aegean ◽

The Mediterranean ◽

North Aegean Sea

As part of its policy, Mediterranean Marine Science started from 2014 to publish a new series of collective article with fisheries-related data from the Mediterranean Sea. In this first collective article we present length frequencies and weight-length relationships for the northern brown shrimp Farfantepenaeus aztecus in the eastern Mediterranean, length-weight relationships for 10 fish species in the North Aegean Sea, the feeding habits for 11 sparid fishes in the North Aegean Sea, a review of the existing literature on the feeding and reproduction of common carp Cyprinus carpio in Anatolia (Turkey) and mouth dimensions and the relationships between mouth area and length for seven freshwater fishes from Lake Volvi (Northern Greece).

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A nested circulation model for the North Aegean Sea

Ocean Science ◽

10.5194/os-3-1-2007 ◽

2007 ◽

Vol 3 (1) ◽

pp. 1-16 ◽

Cited By ~ 31

Author(s):

V. Kourafalou ◽

K. Tsiaras

Keyword(s):

High Resolution ◽

Eastern Mediterranean ◽

Circulation Model ◽

Aegean Sea ◽

Scale Model ◽

Atmospheric Forcing ◽

The North ◽

Basin Scale ◽

North Aegean ◽

North Aegean Sea

Abstract. A multi-nested approach has been employed for numerical simulations in the northern part of the Aegean Sea in the framework of the MFSTEP (Mediterranean Forecast System: Toward Environmental Predictions) project. The high resolution (~1.6 km) hydrodynamic model of the North Aegean Sea (NAS) has been nested within a coarser model of the Eastern Mediterranean (resolution ~3.6 km) which is also nested within a basin scale model for the Mediterranean Sea (resolution of ~7 km). The high resolution of the NAS model allows the representation of topographic details that have never been reproduced in modelling studies of the region. Such details can enhance the simulation of coastal features, but can also influence basin-scale processes, such as the pathways of waters of Black Sea origin inflowing at the Dardanelles Straits and bifurcating through island passages. We employ comparisons of the North Aegean and Eastern Mediterranean models in terms of computed flow fields and distribution of hydrodynamic properties, to evaluate the nesting procedure, the initialization requirements and the ability of a nested model to perform reliable short term simulations that employ high resolution atmospheric forcing, when initialized from a coarser OGCM. We show that the topographic details of the high resolution, nested NAS model affect the distribution of the Dardanelles plume and the evolution of coastal currents, while the imposed high frequency, high resolution atmospheric forcing allows for the formation of an overall energetic flow field after a few days of spin-up period. Increased resolution and smaller coastal depth in the NAS simulations influence the flow through island passages and straits. A longer initialization procedure results in the establishment of stronger currents and better-developed buoyant plumes.

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A nested circulation model for the North Aegean Sea

Ocean Science Discussions ◽

10.5194/osd-3-343-2006 ◽

2006 ◽

Vol 3 (3) ◽

pp. 343-372 ◽

Cited By ~ 1

Author(s):

V. H. Kourafalou ◽

K. P. Tsiaras

Keyword(s):

High Resolution ◽

Eastern Mediterranean ◽

Circulation Model ◽

Aegean Sea ◽

Scale Model ◽

Atmospheric Forcing ◽

The North ◽

Basin Scale ◽

North Aegean ◽

North Aegean Sea

Abstract. A multi-nested approach has been employed for numerical simulations in the northern part of the Aegean Sea in the framework of the MFSTEP (Mediterranean Forecast System: Toward Environmental Predictions) project. The high resolution (~1.6 km) hydrodynamic model of the North Aegean Sea (NAS) has been nested within a coarser model of the Eastern Mediterranean (resolution ~3.6 km) which is also nested within a basin scale model for the Mediterranean Sea (resolution of ~7 km). The high resolution of the NAS model allows the representation of topographic details that have never been reproduced in modelling studies of the region. Such details can enhance the simulation of coastal features, but can also influence basin-scale processes, such as the pathways of waters of Black Sea origin inflowing at the Dardanelles Straits and bifurcating through island passages. We employ comparisons of the North Aegean and Eastern Mediterranean models in terms of computed flow fields and distribution of hydrodynamic properties, to evaluate the nesting procedure, the initialization requirements and the ability of a nested model to perform reliable short term simulations that employ high resolution atmospheric forcing, when initialized from a longer running coarser OGCM. We show that the topographic details of the high resolution, nested NAS model mostly affect the distribution of the Dardanelles plume, while the imposed high frequency, high resolution atmospheric forcing allows for the formation of an overall energetic flow field after a few days of spin-up period. A longer initialization procedure is suggested for the establishment of stronger currents and better developed buoyant plumes.

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High resolution simulations on the North Aegean Sea seasonal circulation

Annales Geophysicae ◽

10.5194/angeo-21-251-2003 ◽

2003 ◽

Vol 21 (1) ◽

pp. 251-265 ◽

Cited By ~ 45

Author(s):

V. H. Kourafalou ◽

K. Barbopoulos

Keyword(s):

High Resolution ◽

Sea Water ◽

Eastern Mediterranean ◽

Aegean Sea ◽

Ocean Model ◽

The Black Sea ◽

The North ◽

Seasonal Characteristics ◽

North Aegean ◽

North Aegean Sea

Abstract. The seasonal characteristics of the circulation in the North Aegean Sea are examined with the aid of a climatological type simulation (three-year run with perpetual year forcing) on a fine resolution grid (2.5 km by 2.5 km). The model is based on the Princeton Ocean Model with a parameterisation of plume dynamics that is employed for the input of waters with hydrographic properties that are different than the properties of basin waters, as the Black Sea Water (BSW) outflow through the Dardanelles Strait and riverine sources. The model is nested with a sequence of coarser regional and basin-wide models that provide for the long-term interaction between the study area and the Eastern Mediterranean at large. The results are employed to discuss the response of the North Aegean to the important circulation forcing mechanisms in the region, namely wind stress, heat and salt fluxes, buoyancy due to rivers and the BSW outflow (which is low in salinity and occasionally low in temperature) and the interaction with the Southern Aegean. The high resolution allows for the detailed representation of the complicated topography that presides in the region. This helps produce a rich eddy field and it allows for variability in the pathways of BSW that has implications in the basin hydrography and circulation.Key words. Oceanography: general (continental shelf processes; numerical modeling)

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Geodetic analysis of the tectonic crustal deformation pattern in the North Aegean Sea, Greece

Mediterranean Geoscience Reviews ◽

10.1007/s42990-021-00049-6 ◽

2021 ◽

Author(s):

Ilias Lazos ◽

Sotirios Sboras ◽

Christos Pikridas ◽

Spyros Pavlides ◽

Alexandros Chatzipetros

Keyword(s):

Crustal Deformation ◽

Aegean Sea ◽

Deformation Pattern ◽

The North ◽

North Aegean ◽

North Aegean Sea

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A three dimensional, full life cycle, anchovy and sardine model for the North Aegean Sea (Eastern Mediterranean): Validation, sensitivity and climatic scenario simulations

Mediterranean Marine Science ◽

10.12681/mms.27407 ◽

2021 ◽

Vol 22 (3) ◽

pp. 653

Author(s):

ATHANASIOS GKANASOS ◽

EUDOXIA SCHISMENOU ◽

KOSTAS TSIARAS ◽

STYLIANOS SOMARAKIS ◽

MARIANNA GIANNOULAKI ◽

...

Keyword(s):

Temperature Increase ◽

Eastern Mediterranean ◽

Larval Growth ◽

Somatic Growth ◽

Aegean Sea ◽

Fish Growth ◽

Prey Concentration ◽

The North ◽

North Aegean ◽

North Aegean Sea

We present the development of a 3D full-lifecycle, individual-based model (IBM) for anchovy and sardine, online coupled to an existing hydrodynamic/biogeochemical low-trophic level (LTL) model for the North Aegean Sea. It was built upon an existing 1D model for the same species and area, with the addition of a horizontal movement scheme. In the model, both species evolve from the embryonic stage (egg+yolk sac larva) to the larval, juvenile, and adult stages. Somatic growth is simulated with the use of a “Wisconsin” type bioenergetics model and fish populations with an adaptation of the ‘super individuals’ (SI) approach. For the reference simulation and model calibration, in terms of fish growth and population biomass, the 2000-2010 period was selected. Interannual biomass variability of anchovy was successfully represented by the model, while the simulated biomass of sardine exhibited low variability and did not satisfactorily reproduce the observed interannual variability from acoustic surveys. The spatial distribution of both species’ biomass was in relatively good agreement with field data. Additional single-species simulations revealed that species compete for food resources. Temperature sensitivity experiments showed that both species reacted negatively to a temperature increase. Anchovy, in particular, was more affected since its spawning and larval growth periods largely overlap with the period of maximum yearly temperature and low prey concentration. Finally, simulation experiments using IPCC climatic scenarios showed that the predicted temperature increase and zooplankton concentration decrease in the future will negatively affect anchovy, resulting in sardine prevalence.

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