Poseidon: A marine environmental monitoring, forecasting and information system for the Greek seas

The scope of this work is twofold: i) to discuss and analyze some principles, issues and problems related to the development and advancement of Operational Oceanography in Greece and ii) to present a real-time monitoring and forecasting system for the Aegean Sea, which is currently under implementation. Operational Oceanography in Greece has become a necessity today, since it can provide aid to find solutions on problems related to societal, economic, environmental and scientific issues. Most of the Greek coastal regions are under pressure, susceptible to damages due to the increasing tendency of the population to move from the inland to the coast, marine environmental pollution, competitive development of the coastal market sector, etc. Moreover, the complex geomorphology of the coastal areas and the interdependence between natural processes and human activities causes significant alterations in this delicate environment. A rational treatment of these problems can be based on integrated coastal zone management (ICZM). An absolutely necessary means for establishing ICZM is the operation of marine moni- toring systems. Such a system ("POSEIDON system") is under implementation by the National Centre for Marine Research. POSEIDON is a comprehensive marine monitoring and forecasting system, that aims to improve environmental surveillance and facilitate sea transport, rescue and safety of life at sea, fishing and aquaculture, protection of the marine ecosystem, etc. POSEIDON is expected to enhance considerably the capabilities to manage, protect and develop the marine resources of the Greek Seas and to promote Greek Operational Oceanography

The Errors-in-Variables approach for the validation of the WAM wave model in the Aegean Sea

In previous studies, wave fi elds from the 3rd-generation wave model WAM-Cycle 4 have been validated by using in situ buoy measurements in the Aegean Sea within the framework of the POSEIDON project; however, limitations of the data sets, concerning mainly the short distance of the buoys from the shore and the short length of the data, render those validation studies incomplete. In this work, signifi cant wave height forecasts obtained from WAM-Cycle 4 wave model are validated by means of TOPEX/Poseidon (T/P) data in specifi c offshore locations in the central part of the North Aegean Sea. The linear structural relationship between the two data sets has been modelled by implementing the Error- In-Variables approach, assuming that both T/P data and WAM results are subjected to errors. The underestimation of signifi cant wave height from WAM, which has been concluded from the comparison with buoys at near-shore points, is also observed from the WAM-T/P comparison at offshore locations, thus being considered of general validity for the Aegean Sea. In addition, a correction relation for the WAM model results, based on the linear structural relationship, is proposed and applied

TIDAL ENERGY: THE CASE OF EURIPUS’ STRAITS

The tidal energy potential of low current tidal and marine currents is investigated in this work. Existing data on the current velocity and sea level at the Euripus’ strait in Evia, Greece, is used to compute the energy yield based on contemporary turbine designs. Requirements, limitations and opportunities concerning the exploitation of low velocity tidal streams are discussed. The exploitation of tidal energy technology in conjunction with RES microgrids is proposed for coastal areas with abundance of sun and wind such as the Mediterranean islands

TIDAL ENERGY: THE CASE OF EURIPUS’ STRAITS

The tidal energy potential of low current tidal and marine currents is investigated in this work. Existing data on the current velocity and sea level at the Euripus’ strait in Evia, Greece, is used to compute the energy yield based on contemporary turbine designs. Requirements, limitations and opportunities concerning the exploitation of low velocity tidal streams are discussed. The exploitation of tidal energy technology in conjunction with RES microgrids is proposed for coastal areas with abundance of sun and wind such as the Mediterranean islands

Theoretical evaluation of the power efficiency of a moored hybrid floating platform for wind and wave energy production in the Greek seas

In this study, an extreme value analysis of wind and wave parameters is presented for three specific locations in the Greek seas that are known to be advantageous in terms of joint power production (both offshore wind and wave) and bathymetric conditions. The analysis is conducted via the Peak-Over-Threshold method, examining wind speed, significant wave height and peak wave period data from the ERA5 reanalysis dataset. Moreover, a multi-purpose floating platform suitable for offshore energy production is presented, which combines wind and wave energy resources exploitation and can be adequately utilized at the selected locations. The analysis is built to incorporate the solutions of the diffraction, motion-dependent and pressure-dependent radiation problems around the floating structure, along with the mooring line and wind turbine (WT) characteristics. Subsequently, a coupled hydro-aero-elastic analysis was performed in the frequency domain, while a dynamic analysis was conducted in order to evaluate the mooring characteristics. Lastly, offshore wind output and absorbed wave energy values were estimated, and different types of mooring systems were compared in terms of efficiency. It has been concluded that the wind energy capacity factor is higher than 50% in all the examined locations, and by the mooring system comparison, the tension-leg platform (TLP) represents the best-case scenario for wave energy absorption

CoCoNet: towards coast to coast networks of Marine Protected Areas (from the shore to the high and deep sea), coupled with sea-based wind energy potential.

Abstract This volume contains the main results of the EC FP7 “The Ocean of Tomorrow” Project CoCoNet, divided in two sections: 1) a set of guidelines to design networks of Marine Protected Areas in the Mediterranean and the Black Seas; 2) a smart wind chart that will allow evaluating the possibility of installing Offshore Wind Farms in both seas. The concept of Cells of Ecosystem Functioning, based on connectivity, is introduced to define natural units of management and conservation. The definition of Good Environmental Status, as defined in the Marine Strategy Framework Directive, is fully embraced to set the objectives of the project, by adopting a holistic approach that integrates a full set of disciplines, ranging from physics to bio-ecology, economics, engineering and many sub-disciplines. The CoCoNet Consortium involved scientist sfrom 22 states, based in Africa, Asia, and Europe, contributing to build a coherent scientific community

CoCoNet: towards coast to coast networks of marine protected areas (from the shore to the high and deep sea), coupled with sea-based wind energy potential

This volume contains the main results of the EC FP7 “The Ocean of Tomorrow” Project CoCoNet, divided in two sections: 1) a set of guidelines to design networks of Marine Protected Areas in the Mediterranean and the Black Seas; 2) a smart wind chart that will allow evaluating the possibility of installing Offshore Wind Farms in both seas. The concept of Cells of Ecosystem Functioning, based on connectivity, is introduced to define natural units of management and conservation. The definition of Good Environmental Status, as defined in the Marine Strategy Framework Directive, is fully embraced to set the objectives of the project, by adopting a holistic approach that integrates a full set of disciplines, ranging from physics to bio-ecology, economics, engineering and many sub-disciplines. The CoCoNet Consortium involved scientist sfrom 22 states, based in Africa, Asia, and Europe, contributing to build a coherent scientific community.peer-reviewe

Marine Renewable Energy Clustering in the Mediterranean Sea: The Case of PELAGOS Project

The main ideas presented in this work are an outcome of the Interreg MED project PELAGOS (Promoting innovative nEtworks and cLusters for mArine renewable energy synerGies in Mediterranean cOasts and iSlands). Since Blue Energy development is at its very beginning in the Mediterranean Sea, the aim of the paper is to present and discuss in depth the key-issues for a Marine Renewable Energy (MRE) cluster development in the Mediterranean and reveal its necessity for the commercial and sustainable development of Blue Energy in the area. This cluster is expected to stimulate the relevant Blue Energy sectors under the perspective of smart and sustainable growth. A healthy cluster is based on an efficient cluster policy. The main policy constituents (innovation, legislation and financial frameworks) are discussed taking into account the interrelated characteristics that are expected to specify the commercial development of MRE in the area. Key issues that can contribute to the establishment and acceleration of deployment of the related technological innovation are identified, and existent hindrances and challenges encountered in MRE sector are determined. The importance of solid financing instruments and strong collaborations among interested stakeholders is also highlighted for the viability of the MRE cluster. Finally, as an example of the cluster activities at a national level, the Greek Hub for Blue Energy is introduced. In this respect, aspects in terms of its structure and the services provided to its members are analyzed