The development of METAL-WRF Regional Model for the description of dust mineralogy in the atmosphere

The mineralogical composition of airborne dust particles is an important but often neglected parameter for several physiochemical processes, such as atmospheric radiative transfer and ocean biochemistry. We present the development of the METAL-WRF module for the simulation of the composition of desert dust minerals in atmospheric aerosols. The new development is based on the GOCART-AFWA dust module of WRF-Chem. A new wet deposition scheme has been implemented in the dust module alongside the existing dry deposition scheme. The new model includes separate prognostic fields for nine (9) minerals: illite, kaolinite, smectite, calcite, quartz, feldspar, hematite, gypsum, and phosphorus, derived from the GMINER30 database and also iron derived from the FERRUM30 database. Two regional model sensitivity studies are presented for dust events that occurred in August and December 2017, which include a comparison of the model versus elemental dust composition measurements performed in the North Atlantic (at Izaña Observatory, Tenerife Island) and in the eastern Mediterranean (at Agia Marina Xyliatos station, Cyprus Island). The results indicate the important role of dust minerals, as dominant aerosols, for the greater region of North Africa, South Europe, the North Atlantic, and the Middle East, including the dry and wet depositions away from desert sources. Overall, METAL-WRF was found to be capable of reproducing the relative abundances of the different dust minerals in the atmosphere. In particular, the concentration of iron (Fe), which is an important element for ocean biochemistry and solar absorption, was modeled in good agreement with the corresponding measurements at Izaña Observatory (22% overestimation) and at Agia Marina Xyliatos site (4% overestimation). Further model developments, including the implementation of newer surface mineralogical datasets, e.g., from the NASA-EMIT satellite mission, can be implemented in the model to improve its accuracy.This study was supported by the Hellenic Foundation for Research and Innovation project Mineralogy of Dust Emissions and Impacts on Environment and Health (MegDeth - HFRI no. 703). Part of this study was conducted within the framing of the AERO-EXTREME (PID2021-125669NB-I00) project funded by the State Research Agency/Agencia Estatal de Investigación of Spain and the European Regional Development Funds

Χαρακτηρισμός του υπεράκτιου αιολικού και κυματικού δυναμικού: μια ολοκληρωμένη προσέγγιση για συνεκμετάλλευση

During the last years, under the global change considerations and the need for a clean energy future, several countries have invested on the exploitation of renewable energy resources. Among the various forms of renewables, wind energy has gained through the years a significant role in the existing energy mix. Towards this direction, several countries, especially in Europe, have extended the wind energy exploitation to offshore regions. Furthermore, as the demand of wind energy is rising suitable near-shore shallow water sites become sparse driving the industry to deep offshore areas. There the resource is high but the problems are the same. The high installation, operation and maintenance costs and the variability of the final output are issues that need to be addressed. The latter is one of the most important problems for the electrical grid especially when the penetration levels of renewables are to be increased significantly. A possible solution for reducing the variability of the power output from renewables could be the combined wind and wave energy exploitation in areas that the two resources reveal different characteristics.In this thesis, a detailed resource characterization has been performed that takes into account the diversity of the two recourses and the benefits of their optimum combination in an extended area and for various timescales. In particular, the main characteristics of the two resources, for the offshore area of Europe, have been analyzed in terms of availability, variability and potential impact from extreme values. Furthermore, an analysis of the two resources has been performed in terms of coherence and complementarity. For the areas indicated by the previous mentioned analysis the possible benefits from the combined use have been evaluated. Finally, an analysis has been performed in order to identify the optimum wind and wave energy mix that will increase the reliability of the system, in terms of availability and variability. The latter has been assessed for its sensitivity in different timescales and in areas of different characteristics.Τα τελευταία χρόνια η ανάγκη για προστασία του περιβάλλοντος, εξοικονόμηση ενεργειακών πόρων και αντιμετώπιση της κλιματικής αλλαγής οδήγησε στην ολοένα και αυξανόμενη εκμετάλλευση των ανανεώσιμων πηγών ενέργειας (ΑΠΕ). H εκμετάλλευση των ανανεώσιμων πηγών ενέργειας (ΑΠΕ). Ένας από τους πιο δυναμικά αναπτυσσόμενους κλάδους των ΑΠΕ στηρίζεται στην εκμετάλλευση του υπεράκτιου αιολικού δυναμικού. Πολλές χώρες ανά τον κόσμο, με κυρίαρχες τις Ευρωπαικές, σαν επόμενο βήμα έχουν προσανατολίσει τους στόχους τους στην επέκταση των υπεράκτιων πάρκων σε περιοχές με ακόμη μεγαλύτερα βάθη. Παρόλο όμως που το δυναμικό είναι μεγαλύτερο, τα προβλήματα παραμένουν τα ίδια και συνοψίζονται στα ακόλουθα: στο κόστος εγκτάστασης, λειτουργίας, συντήρησης και στην διακύμανση της τελικής παραγόμενης ισχύος. Το τελευταίο αποτελεί ένα από τα πιo σημαντικά μειoνεκτήματα των ΑΠΕ και ένα από τα πιo σημαντικά θέματα προς επίλυση και διαχείρηση. Προς αυτήν την κατεύθυνση, λύση μπορεί να αποτελέσει η συνεκμετάλλευση του αιολικού και του κυματικού δυναμικού σε περιοχές που τα δύο δυναμικά παρουσιάζουν διαφορετικά χαρακτηριστικά. Στα πλαίσια αυτής της διατριβής έγινε για πρώτη φορά προσπάθεια απο κοινού μελέτης του διαθέσιμου υπεράκτιου αιολικού και κυματικού δυναμικού, με υψηλή χωροχρονική ανάλυση και για εκτεταμένη περιοχή. Συγκεκριμένα μελετήθηκαν τα βασικά χαρακτηριστικά του υπεράκτιου αιολικού και θαλάσσιου κυματικού δυναμικού της Ευρώπης όσον αφορά την διαθεσιμότητα και την μεταβλητότητα σε διάφορες κλίμακες ενώ στη συνέχεια πραγματοποιήθηκε μελέτη για τον εντοπισμό χωροχρονικών συσχετίσεων μεταξύ τους. Βάσει των αποτελεσμάτων αυτών, πραγματοποιήθηκε περαιτέρω ανάλυση αναφορικά με τα πλεονεκτήματα ή μη της κοινής χρήσης. Τέλος, πραγματοποιήθηκε συσχέτιση της βελτίωσης της παραγόμενης ισχύος με τα τοπικά φυσιογραφικά χαρακτηριστικά των περιοχών, τις διάφορες χρονικές κλίμακες και ανάλογα με το ποσοστό συμμετοχής κάθε δυναμικού στο τελικό ενεργειακό μείγμα

Offshore Wind and Wave Energy Resource Characterization: An Integrated Approach for Combined Exploitation

Τα τελευταία χρόνια η ανάγκη για προστασία του περιβάλλοντος, εξοικονόμηση ενεργειακών πόρων και αντιμετώπιση της κλιματικής αλλαγής οδήγησε στην ολοένα και αυξανόμενη εκμετάλλευση των ανανεώσιμων πηγών ενέργειας (ΑΠΕ). H εκμετάλλευση των ανανεώσιμων πηγών ενέργειας (ΑΠΕ). Ένας από τους πιο δυναμικά αναπτυσσόμενους κλάδους των ΑΠΕ στηρίζεται στην εκμετάλλευση του υπεράκτιου αιολικού δυναμικού. Πολλές χώρες ανά τον κόσμο, με κυρίαρχες τις Ευρωπαικές, σαν επόμενο βήμα έχουν προσανατολίσει τους στόχους τους στην επέκταση των υπεράκτιων πάρκων σε περιοχές με ακόμη μεγαλύτερα βάθη. Παρόλο όμως που το δυναμικό είναι μεγαλύτερο, τα προβλήματα παραμένουν τα ίδια και συνοψίζονται στα ακόλουθα: στο κόστος εγκτάστασης, λειτουργίας, συντήρησης και στην διακύμανση της τελικής παραγόμενης ισχύος. Το τελευταίο αποτελεί ένα από τα πιo σημαντικά μειoνεκτήματα των ΑΠΕ και ένα από τα πιo σημαντικά θέματα προς επίλυση και διαχείρηση. Προς αυτήν την κατεύθυνση, λύση μπορεί να αποτελέσει η συνεκμετάλλευση του αιολικού και του κυματικού δυναμικού σε περιοχές που τα δύο δυναμικά παρουσιάζουν διαφορετικά χαρακτηριστικά. Στα πλαίσια αυτής της διατριβής έγινε για πρώτη φορά προσπάθεια απο κοινού μελέτης του διαθέσιμου υπεράκτιου αιολικού και κυματικού δυναμικού, με υψηλή χωροχρονική ανάλυση και για εκτεταμένη περιοχή. Συγκεκριμένα μελετήθηκαν τα βασικά χαρακτηριστικά του υπεράκτιου αιολικού και θαλάσσιου κυματικού δυναμικού της Ευρώπης όσον αφορά την διαθεσιμότητα και την μεταβλητότητα σε διάφορες κλίμακες ενώ στη συνέχεια πραγματοποιήθηκε μελέτη για τον εντοπισμό χωροχρονικών συσχετίσεων μεταξύ τους. Βάσει των αποτελεσμάτων αυτών, πραγματοποιήθηκε περαιτέρω ανάλυση αναφορικά με τα πλεονεκτήματα ή μη της κοινής χρήσης. Τέλος, πραγματοποιήθηκε συσχέτιση της βελτίωσης της παραγόμενης ισχύος με τα τοπικά φυσιογραφικά χαρακτηριστικά των περιοχών, τις διάφορες χρονικές κλίμακες και ανάλογα με το ποσοστό συμμετοχής κάθε δυναμικού στο τελικό ενεργειακό μείγμα.During the last years, under the global change considerations and the need for a clean energy future, several countries have invested on the exploitation of renewable energy resources. Among the various forms of renewables, wind energy has gained through the years a significant role in the existing energy mix. Towards this direction, several countries, especially in Europe, have extended the wind energy exploitation to offshore regions. Furthermore, as the demand of wind energy is rising suitable near-shore shallow water sites become sparse driving the industry to deep offshore areas. There the resource is high but the problems are the same. The high installation, operation and maintenance costs and the variability of the final output are issues that need to be addressed. The latter is one of the most important problems for the electrical grid especially when the penetration levels of renewables are to be increased significantly. A possible solution for reducing the variability of the power output from renewables could be the combined wind and wave energy exploitation in areas that the two resources reveal different characteristics. In this thesis, a detailed resource characterization has been performed that takes into account the diversity of the two recourses and the benefits of their optimum combination in an extended area and for various timescales. In particular, the main characteristics of the two resources, for the offshore area of Europe, have been analyzed in terms of availability, variability and potential impact from extreme values. Furthermore, an analysis of the two resources has been performed in terms of coherence and complementarity. For the areas indicated by the previous mentioned analysis the possible benefits from the combined use have been evaluated. Finally, an analysis has been performed in order to identify the optimum wind and wave energy mix that will increase the reliability of the system, in terms of availability and variability. The latter has been assessed for its sensitivity in different timescales and in areas of different characteristics

Optimization of Numerical Weather/Wave Prediction Models based on Information Geometry and Computational Techniques

The last years a new highly demanding framework has been set for environmental sciences and applied mathematics as a result of the needs posed by issues that are of interest not only of the scientific community but of today’s society in general: global warming, renewable resources of energy, natural hazards can be listed among them. Two are the main directions that the research community follows today in order to address the above problems: The utilization of environmental observations obtained from in situ or remote sensing sources and the meteorological-oceanographic simulations based on physical-mathematical models. In particular, trying to reach credible local forecasts the two previous data sources are combined by algorithms that are essentially based on optimization processes. The conventional approaches in this framework usually neglect the topological-geometrical properties of the space of the data under study by adopting least square methods based on classical Euclidean geometry tools. In the present work new optimization techniques are discussed making use of methodologies from a rapidly advancing branch of applied Mathematics, the Information Geometry. The latter prove that the distributions of data sets are elements of non-Euclidean structures in which the underlying geometry may differ significantly from the classical one. Geometrical entities like Riemannian metrics, distances, curvature and affine connections are utilized in order to define the optimum distributions fitting to the environmental data at specific areas and to form differential systems that describes the optimization procedures. The methodology proposed is clarified by an application for wind speed forecasts in the Kefaloniaisland, Greece

Regional Climatic Features of the Arabian Peninsula

The climate of the Arabian Peninsula is characterized by significant spatial and temporal variations, due to its complex topography and the large-scale atmospheric circulation. Furthermore, the role of dust in the formation of regional climate is considered to be crucial. In this work, the regional climatology for the Arabian Peninsula has been studied by employing a high resolution state of the art atmospheric model that included sophisticated physical parameterization schemes and online treatment of natural aerosol particles. The simulations covered a 30-year period (1986–2015) with a temporal resolution of 3 h and a spatial distance of 9 km. The main focus was given to the spatial and temporal variations of mean temperature and temperature extremes, wind speed and direction, and relative humidity. The results were evaluated using in situ measurements indicating a good agreement. An examination of possible climatic changes during the present climate was also performed through a comprehensive analysis of the trends of mean temperature and temperature extremes. The statistical significant trend values were overall positive and increased over the northwestern parts of the examined area. Similar spatial distributions were found for the daily minimum and maximum temperatures. Higher positive values emerged for the daily maxima

Wave energy potential in the Eastern Mediterranean Levantine Basin. An integrated 10-year study

The article of record as published may be found at http://dx.doi.org/10.1016/j.renene.2014.03.0510960-1481The main characteristics of wave energy potential over Eastern Mediterranean Levantine Basin, an area of increased interest for energy resources exploration/exploitation, is presented in this work. In particular, an integrated hindcasting platform consisting of state-of-the-art wind-wave numerical models at a very high resolution mode is utilized to produce a 10-year database for the wave energy potential in the Levantine Basin and the environmental parameters that affect it. The numerical results are analyzed by means of a variety of statistical measures focusing, apart from the conventional statistical information, on the potential impact of extreme values and the probability distribution functions that optimally describe the spatial and temporal distribution of the wave power potential over the Eastern Mediterranean sea area. The regions with increased values of wave energy potential are mainly the western and southern coastlines of Cyprus island, the sea area of Lebanon and Israel, as well as the coastline of Egypt especially around Alexandria. Over these areas, relatively low but also stable, and hence exploitable, wave energy potential is revealed. However, non-trivial impact of infrequent values is also recorded.E-WAVE project (Project Protocol Number TEXNOLOGIA/ENEPG/0609(BIE)/01)Research Promotion Foundation of the Republic of CyprusEuropean Regional Development FundE-WAVE project (Project Protocol Number TEXNOLOGIA/ENEPG/0609(BIE)/01)Research Promotion Foundation of the Republic of CyprusEuropean Regional Development Fun