quotes Ερευνητικοί Άξονες

 

 

 

 Μετρήσεις, έλεγχος ποιότητας και μέθοδοι επεξεργασίας και ομογενοποίησης μετεωρολογικών και περιβαλλοντικών χρονοσειρών

Σταθερά ισότοπα (18Ο και 2Η) στη βροχή και τους υδρατμούς

Υπεριώδης ακτινοβολία: μετρήσεις, μαθηματική προτυποποίηση και βιολογικές δόσεις

Ηλιακή ακτινοβολία: μετρήσεις, μοντέλα και εφαρμογές στην ηλιακή ενέργεια

 Εφαρμογή μεθόδων τεχνητής νοημοσύνης σε μετεωρολογικές και περιβαλλοντικές χρονοσειρές

Μαθηματικά πρότυπα πρόγνωσης καιρού και ατμοσφαρικής ρύπανσης

solarmaps
quotes Ερευνητικά Έργα

MENA Hybrid Solar System (HYMENSO), 2016 – 2018

Intelligent Methods for solar resource and forecasting with the use of high spatial and temporal resolution datasets, 2016 – 2017

Pollution monitoring of ship emissions: an integrated approach for harbors of the Adriatic basin (Poseidon) (2014 - 2015)

Direct Normal Irradiance Nowcasting Methods for Optimized Operation of Concentrating Solar Technologies, DNICast (2013-2017)

ENvironmental Optimization of IRrigation Management with the Combined uSe and Integration of High PrecisIon Satellite Data, Advanced Modelling, Process Control and Business Innovation, ENORASIS (2012-2014)

Ελληνικό Δίκτυο Ηλιακής Ενέργειας (2011-2013)

Contribution of Emission Sources on the Air quality of the Port-cities in Greece and Italy, CESAPO (2011-2014)

Weather Intelligence for Renewable Energy, WIRE (2010-2014)

Stable Isotopes in Biosphere-Atmosphere-Earth System Research, SIBAE (2009-2013)

 

 

 

 

 

 
solarmaps

Ανακοινώσεις

Συμμετοχή του ΕΦΑΠ2 στο EGU Geneal Assembly, Vienna, Austria, 12-17 April 2015

Δημοσιεύτηκε στις: 07/04/2015

Το Εργαστήριο Φυσικής της Ατμόσφαιρας συμμετέχει στο General Assembly of the European Geosciences Union (Vienna, Austria, 12-17 April 2015) με τις επόμενες παρουσιάσεις.

 

 Προφορική παρουσίαση:

Estimation of aerosol optical properties from all-sky imagers

Andreas Kazantzidis (1), Panagiotis Tzoumanikas (1), Vasilios Salamalikis (1), Stefan Wilbert (2), and Christoph Prahl (2)

(1) Laboratory of Atmospheric Physics, University of Patras, Patras, Greece, (2) Deutsches Zentrum für Luft- und Raumfahrt e.V., Institute of Solar Research, Plataforma Solar de Almería (PSA), Tabernas, Spain

Aerosols are one of the most important constituents in the atmosphere that affect the incoming solar radiation, either directly through absorbing and scattering processes or indirectly by changing the optical properties and lifetime of clouds. Under clear skies, aerosols become the dominant factor that affect the intensity of solar irradiance reaching the ground. It has been shown that the variability in direct normal irradiance (DNI) due to aerosols is more important than the one induced in global horizontal irradiance (GHI), while the uncertainty in its calculation is dominated by uncertainties in the aerosol optical properties. In recent years, all-sky imagers are used for the detection of cloud coverage, type and velocity in a bouquet of applications including solar irradiance resource and forecasting. However, information about the optical properties of aerosols could be derived with the same instrumentation. In this study, the aerosol optical properties are estimated with the synergetic use of all-sky images, complementary data from the Aerosol Robotic Network (AERONET) and calculations from a radiative transfer model. The area of interest is Plataforma Solar de Almería (PSA), Tabernas, Spain and data from a 5 month period are analyzed. The proposed methodology includes look-up-tables (LUTs) of diffuse sky radiance of Red (R), Green (G) and Blue (B) channels at several zenith and azimuth angles and for different atmospheric conditions (Angström α and β, single scattering albedo, precipitable water, solar zenith angle). Based on the LUTS, results from the CIMEL photometer at PSA were used to estimate the RGB radiances for the actual conditions at this site. The methodology is accompanied by a detailed evaluation of its robustness, the development and evaluation of the inversion algorithm (derive aerosol optical properties from RGB image values) and a sensitivity analysis about how the pre-mentioned atmospheric parameters affect the results

 

 

 

Αφίσες:

Comparison of Artificial Neural Networks and ARIMA statistical models in simulations of target wind time series

Kostantinos Kolokythas, Salamalikis Vasileios, Argiriou Athanassios, and Andreas Kazantzidis

Laboratory of Atmospheric Physics, University of Patras, Patras, Greece

The wind is a result of complex interactions of numerous mechanisms taking place in small or large scales, so, the better knowledge of its behavior is essential in a variety of applications, especially in the field of power production coming from wind turbines. In the literature there is a considerable number of models, either physical or statistical ones, dealing with the problem of simulation and prediction of wind speed. Among others, Artificial Neural Networks (ANNs) are widely used for the purpose of wind forecasting and, in the great majority of cases, outperform other conventional statistical models. In this study, a number of ANNs with different architectures, which have been created and applied in a dataset of wind time series, are compared to Auto Regressive Integrated Moving Average (ARIMA) statistical models. The data consist of mean hourly wind speeds coming from a wind farm on a hilly Greek region and cover a period of one year (2013). The main goal is to evaluate the models ability to simulate successfully the wind speed at a significant point (target). Goodness–of–fit statistics are performed for the comparison of the different methods. In general, the ANN showed the best performance in the estimation of wind speed prevailing over the ARIMA models.

 

 

Lightning activity and aerosols over the Mediterranean

Emmanouil Proestakis (1), Stelios Kazadzis (1), Vassiliki Kotroni (1), Kostas Lagouvardos (1), and Andreas Kazantzidis (2)

(1) National Observatory of Athens, Institute for Environmental Research, Penteli-Athens, Greece, (2) Department of Physics, University of Patras, Patras, Greece

Lightning activity has received extended scientific attention over the past decades. Several international studies on lightning activity and initiation mechanisms have related the increased aerosol concentrations to lightning enhancement. In the frame of TALOS project, we investigated the effect of aerosols on lightning activity over the Mediterranean Sea. Cloud to ground lightning activity data from ZEUS lightning detection network operated and maintained by the National Observatory of Athens, were used along with atmospheric optical depth (AOD) data retrieved by MODIS, on board Aqua satellite. The analysis covers a period of nine years, spanning from 2005 up to 2013. The results show the importance of aerosols in lightning initiation and enhancement. It is shown that the mean AOD of the days with lightning activity per season is larger than the mean seasonal AOD in 90% of the under study domain. Furthermore, lightning activity increase with increasing aerosol loading was found to be more pronounced during summertime and for atmospheric optical depth values up to 0.4. Additionally, during summertime, the spatial analysis showed that the percentage of days with lightning activity is increasing with increasing aerosol loading. Finally, time series for the period 2005-2013 of the days with lightning activity and AOD differences showed similar temporal behavior. Overall, both the spatial and temporal analysis showed that lightning activity is correlated to aerosol loading and that this characteristic is consistent for all seasons.


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