The estimation of an airborne hazardous release and its associated uncertainty from a point source is a necessity for assessing the associated risk and taking possible protective actions. The problem here is to be able to make such an estimation, based on the availability of a rather limited number of sensors measuring pollutant/agent concentrations with a given time resolution. The challenge is to not only provide reliable outcome but also timely results even in operation level. A radically new concept is under development by (a) making full use of the real detailed inflow data and sensors concentration signals, (b) performing in the customisation – pre-emergency – phase only, a quite limited number of steady-state flow and dispersion simulations under reference inflow and release conditions and (c) projection of the steady state/reference results to real atmospheric and release conditions via appropriate novel scaling approaches based on experimental evidence and theory and (d) generating a low computational time demand tool, that can be handled by the operator on duty, even in the extreme cases of very complex topographies. In this study first experimental evidence is provided from a wind-tunnel flow and dispersion experiment in a typical urban area supporting the validity of the whole approach. In addition, the present approach is simultaneously assessing each sensor's signal suitability to be used for source quantification.

During the last 50 years, the vast majority of European countries have relied on coal and imported carbon-containing fuels to meet their growing electricity demand. Coal is the only fossil fuel in significant reserves across Europe. However, the pressing threat of radical climate change and the looming depletion of fossil fuels necessitate a structural transformation from a conventional centralized fossil fuel-based electricity generation system to an innovative decentralized system based on zero carbon (green) energy resources. In this context, one important issue for communities operating coal-based Thermal Power Stations (TPS) nearing retirement is whether the European Union (EU) policy can ensure a socially just development of the coal mining areas during the coal phase-out. The objective is to avoid a decline in living standards and mass immigration. In response to the EU's decarbonization policy, the Greek state has recently decided to retire the lignite-based West Macedonia TPS, which has been in operation since the 1970s. Since its establishment in August 1950, the (initially State-controlled) Greek Public Power Corporation (PPC) has undertaken the responsibility to operate the quarries and the six local TPS, offering approximately 25,000 direct and indirect jobs. Over the last 50 years, the extraction of lignite and the operation of the 4500 MWe TPS of West Macedonia has been the primary economic activity, accounting for nearly 45% of the entire Region's GDP. While both the Greek state and the EU have prepared and presented plans to financially support local communities and encourage new private and public investments, local citizens remain anxious about their future. The present study investigates the attitude of young scientists towards the forthcoming radical changes linked to the green transition in seriously affected EU Regions, with a focus on West Macedonia. The proposed analysis in West Macedonia reveals the skepticism of young people regarding the speed of the green transition and concerns about significant migration and potential brain drain. On the other hand, the implementation of EU initiatives, including the involvement of young scientists in the planned new green energy-related activities, offers a promising alternative solution. This engagement can lead to the successful integration of local communities into the sustainable and green future envisioned by the EU.

The government decision to promote the change of energy mix has led to a serious decrease in industrial activities in the energy basin of Western Macedonia and subsequently had a positive influence on the air quality of the region. To examine the fact and estimate the current atmospheric emission sources, PM10 samples were collected at different sites in Western Macedonia, Greece, from February 2022 to May 2023 and were analyzed for metallic components, major ions, and PAHs. The dataset was then analyzed using PMF and CMB model to identify the possible emission sources. In this study, the first results are presented and discussed.

Forest species in the course of their evolution have experienced several environmental challenges, which since historic times include anthropogenic pollution. The effects of pollution on the genetic and epigenetic diversity in black pine (Pinus nigra) forests were investigated in the Amyntaio - Ptolemais - Kozani Basin, which has been for decades the largest lignite mining and burning center of Greece, with a total installed generating capacity of about 4.5 GW, operating for more than 70 years and resulting in large amounts of primary air pollutant emissions, mainly SO2, NOx and PM10. P. nigra, a biomarker for air pollution and a keystone species of affected natural ecosystems, was examined in terms of phenology (cone and seed parameters), genetics (283 AFLP loci) and epigenetics (606 MSAP epiloci), using two populations (exposed to pollution and control) of the current (mature trees) and future (embryos) stand. It was found that cone, seed, as well as genetic diversity parameters, did not show statistically significant differences between the exposed population and the control. Nevertheless, statistically significant differences were detected at the population epigenetic level. Moreover, there was a further differentiation regarding the intergenerational comparison: while the epigenetic diversity does not substantially change in the two generations assessed in the control population, epigenetic diversity is significantly higher in the embryo population compared to the parental stand in the exposed population. This study sheds a light to genome dynamics in a forest tree population exposed to long term atmospheric pollution burden and stresses the importance of assessing both genetics and epigenetics in biomonitoring applications.

Airborne particulate matter (PM) with an aerodynamic diameter of 10μm or less has severe negative effects on human health. In many European urban environments, small residential heating appliances contribute significantly to the degradation of air quality by generating a substantial quantity of PM. In the present work, trends of PM1, PM2.5 and PM10 have been evaluated in a medium – sized European city, Ioannina, NW Greece. We analyze the most recent available surface concentration observations for the period 2014 – March 2021. The analysis showed that even if there is a strict legislation at EU and national level, PM emissions from residential combustion processes contribute significantly to air pollution during wintertime in Ioannina. Local topography, local-scale meteorological conditions and local sources impose a local plan of action to monitor air pollution. The analysis highlights the need for coordinated actions in local and national scale.

In view of the EU decarbonization policy implementation, the Greek government has recently decided the permanent retirement of lignite based thermal power stations (TPS) of West Macedonia, being in operation since the 70’s. For the last fifty years, the Public Power Corporation has undertaken the responsibility to run the quarries and the thermal power stations offering almost 15000 direct and indirect job positions. In this context and despite the significant environmental impacts in the wider area, the lignite extraction and the operation of the TPS of Ptolemaida, Amintaio, Kardia and Agios Dimitrios have been the major economic activity of the entire prefecture for the last five decades. Although the Greek government has prepared quite ambitious plans to financially support the local communities and to encourage public and private investments, local societies are quite anxious about their future. To this end, the present work not only investigates the energy transition of the West Macedonia but also analyzes the attitude of the local people towards the radical changes anticipated in the near future. Emphasis is put on examining the answers of young scientists, most of them expecting to work in the energy supply chain of the under retirement TPS. The results of this analysis are quite interesting and underline the danger of significant immigration and brain drain for the area, while the involvement in planned energy installations may also be a serious alternative solution.

In surface mines, various activities (e.g., excavations, loading and unloading of material, moving vehicles on unpaved haul roads, etc.) represent significant sources of fugitive dust. The estimation of dust generation from each individual source is a basic step in planning and implementation decision-making systems regarding the air quality of the surrounding area. Typically, this can be obtained by using emission factor or prediction-type equations. A detailed study was carried out at four surface lignite mines to determine PM emission factors and to develop the prediction-type equations of various surface mining activities. In this work, the data, method and results referring to the stacker, one of and the significant fugitive dust emissions source in mining operations are presented and analyzed.

Mesoscale numerical weather prediction models usually provide information regarding environmental parameters near urban areas at a spatial resolution of the order of thousands or hundreds of meters, at best. If detailed information is required at the building scale, an urban-scale model is necessary. Proper definition of the boundary conditions for the urban-scale simulation is very demanding in terms of its compatibility with environmental conditions and numerical modeling. Here, steady-state computational fluid dynamics (CFD) microscale simulations of the wind and thermal environment are performed over an urban area of Kozani, Greece, using both the k-ε and k-ω SST turbulence models. For the boundary conditions, instead of interpolating vertical profiles from the mesoscale solution, which is obtained with the atmospheric pollution model (TAPM), a novel approach is proposed, relying on previously developed analytic expressions, based on the Monin Obuhkov similarity theory, and one-way coupling with minimal information from mesoscale indices (Vy = 10 m, Ty = 100 m, L*). The extra computational cost is negligible compared to direct interpolation from mesoscale data, and the methodology provides design phase flexibility, allowing for the representation of discrete urban-scale atmospheric conditions, as defined by the mesoscale indices. The results compared favorably with the common interpolation practice and with the following measurements obtained for the current study: SODAR for vertical profiles of wind speed and a meteorological temperature profiler for temperature. The significance of including the effects of diverse atmospheric conditions is manifested in the microscale simulations, through significant variations (~30%) in the critical building-related design parameters, such as the surface pressure distributions and local wind patterns.

The identification of PM sources and their contribution to measured PM concentrations is crucial for the environmental policy making since the findings be able to conduce to the development of relevant legislation in order to achieve effective air quality manage. In this study, the sources of PM10 at three receptors with different characteristics, within the Western Macedonia (WM) in NW Greece, were investigated: S1 in the center of Kozani, a medium sized city located at the southern edge of the industrial axis of WM, where urban activities and traffic density occur. S2 in the city of Ptolemaida, a medium sized city located in the centre of industrial zone, and S3 in the village of Eratyra, a rural residential district outside of the industrial area. For this purpose, the multivariate Positive Matrix Factorization (EPA PMF 5.0) receptor model was applied on elemental data. Specifically, PM10 samples, obtained by filtration during 1-year sampling campaign, were analyzed by ICP-MS instrument. Twenty-five elements were detected at quantifiable concentrations in the investigated PM samples. For the particle samples obtained in areas within and proximal from mining and power station operations, a six-factor model gave source profiles that attributed to be vehicle exhaust, road dust, soil dust, coal combustion, oil combustion and biomass burning. Furthermore, at the background site, the major contributors were biomass burning, soil dust and oil burning while no distant transport from industrial axis was recorded.

In the operation of large open-pit lignite mines (extracting and handling excavation materials) a series of significant fugitive dust emission sources are recorded. The quantification of the emissions of each source and the investigation of atmospheric dispersion are subjects of great interest for the development and implementation of air quality management systems in the neighbouring residential areas. The study aims to investigate and locate the fugitive dust sources in the surface mines operated in Western Macedonia in NW Greece and quantify their contribution to the total fugitive dust (PM10) emissions produced by the mines' activities. The contribution of each emission source recorded was quantified. An effort was also made to investigate the dispersion of fugitive dust emitted from each individual mine and source activity and assess the contribution of the mining activities to the air quality of the surrounding areas, by using a three-dimensional, nestable, prognostic meteorological, and air pollution model. The results can contribute to the implementation of measures and scenarios for the air quality management in the area.

This paper provides the performance evaluation of the meteorological component of The Air Pollution Model (TAPM), a nestable prognostic model, in predicting meteorological variables in urban areas, for both its surface layer and atmospheric boundary layer (ABL) turbulence parameterizations. The model was modified by incorporating four urban land surface types, replacing the existing single urban surface. Control runs were carried out over the wider area of Kozani, an urban area in NW Greece. The model was evaluated for both surface and ABL meteorological variables by using measurements of near-surface and vertical profiles of wind and temperature. The data were collected by using monitoring surface stations in selected sites as well as an acoustic sounder (SOnic Detection And Ranging (SODAR), up to 300 m above ground) and a radiometer profiler (up to 600 m above ground). The results showed the model demonstrated good performance in predicting the near-surface meteorology in the Kozani region for both a winter and a summer month. In the ABL, the comparison showed that the model’s forecasts generally performed well with respect to the thermal structure (temperature profiles and ABL height) but overestimated wind speed at the heights of comparison (mostly below 200 m) up to 3–4 ms−1.

During a whole year (March 2003 to February 2004), several filters that capture airborne particles were collected from seven sampling sites spread throughout the Ptolemais-Kozani region (Western Macedonia), northern Greece. Environmental Scanning Electron Microscopy (ESEM), coupled with Energy Dispersive X-Ray analysis (EDX) was employed for the characterisation of the airborne particles. A classification of these airborne particles is attempted in this study. Aerosols with various morphological characteristics (angular, irregular, rounded, spherical, spheroidal, acicular), variable size (mostly between 5ßm and 20pm) and composition (aluminosilicates, oxides, carbonates, sulphates, metallic) were recognized. The airborne particulates were also categorized according to their origin. Geogenie, biogenic, anthropogenic (mainly fly ash released from lignite-fired power plants), carbonaceous and metalliferous (mainly iron and copper enriched) were the main categories. A database of characteristic airborne particles from Kozani area is being created using a simple software package, in order to help similar studies in the future.

Atmospheric modeling is considered an important tool with several applications such as prediction of air pollution levels, air quality management, and environmental impact assessment studies. Therefore, evaluation studies must be continuously made, in order to improve the accuracy and the approaches of the air quality models. In the present work, an attempt is made to examine the air pollution model (TAPM) efficiency in simulating the surface meteorology, as well as the SO 2 concentrations in a mountainous complex terrain industrial area. Three configurations under different circumstances, firstly with default datasets, secondly with data assimilation, and thirdly with updated land use, ran in order to investigate the surface meteorology for a 3-year period (2009–2011) and one configuration applied to predict SO 2 concentration levels for the year of 2011.The modeled hourly averaged meteorological and SO 2 concentration values were statistically compared with those from five monitoring stations across the domain to evaluate the model’s performance. Statistical measures showed that the surface temperature and relative humidity are predicted well in all three simulations, with index of agreement (IOA) higher than 0.94 and 0.70 correspondingly, in all monitoring sites, while an overprediction of extreme low temperature values is noted, with mountain altitudes to have an important role. However, the results also showed that the model’s performance is related to the configuration regarding the wind. TAPM default dataset predicted better the wind variables in the center of the simulation than in the boundaries, while improvement in the boundary horizontal winds implied the performance of TAPM with updated land use. TAPM assimilation predicted the wind variables fairly good in the whole domain with IOA higher than 0.83 for the wind speed and higher than 0.85 for the horizontal wind components. Finally, the SO 2 concentrations were assessed by the model with IOA varied from 0.37 to 0.57, mostly dependent on the grid/monitoring station of the simulated domain. The present study can be used, with relevant adaptations, as a user guideline for future conducting simulations in mountainous complex terrain.

This paper describes the dynamic seminar management system named “e-Sem”, developed according to the open-source software philosophy. Due to its dynamic management functionality, it can equally adapt to any education environment (Primary, Secondary, Tertiary). The purpose of the proposed dynamic system is ease of use and handling, by any class of users, without the need of special guidance. Also, students are given the opportunity to: a) register as users; b) enroll in seminars in a simple way; c) receive e-learning material at any time of day any day of week, and d) be informed of new announcements concerning the seminar in which they are enrolled. In addition, the administrator and the tutors have a number of tools such as : management seminars and trainees in a friendly way, sending educational material as well as new announcements to the trainees; the possibility of electronic recording of presence or absence of the trainees in a seminar, and direct printing of a certificate of successful attendance of a seminar for each trainee. The application also offers features such as electronic organization, storage and presentation of educational material, overcoming the limiting factors of space and time of classical teaching, thus creating a dynamic environment.

The rapid urbanization in the recent decades modified negatively the urban environments. The Urban Heat Island (UHI) effect is a phenomenon which came as a consequence to this urbanization and has damaging effects in several areas, the ecological, socio-ecological, economical and climatical included. This study investigates the UHI in a small size town in northwestern Greece for four years (2011–2014), by analyzing hourly air temperatures and meteorological data in one urban-traffic and one rural station. Furthermore, the study investigates the dependence of the UHI to the basic atmospheric forcings and comperes the findings with the measured results from other works in Greece. It is worth mentioning from the inter-comparison that despite the fact that Kozani is the smallest and less populated town, Kozani’s UHI has approximately the magnitude of the one measured in Thessaloniki and it is higher from those measured in Volos and Agrinio during the winter period. Finally, the study investigates the energy demands in the city regarding the cooling and heating hours and comments on the impacts of the UHI.

Periods of abnormally high concentrations of atmospheric pollutants, defined as air pollution episodes, can cause adverse health effects. Southern European countries experience high particulate matter (PM) levels originating from local and distant sources. In this study, we investigated the occurrence and nature of extreme PM10 (PM with an aerodynamic diameter ≤10 μm) pollution episodes in Greece. We examined PM10 concentration data from 18 monitoring stations located at five sites across the country: (1) an industrial area in northwestern Greece (Western Macedonia Lignite Area, WMLA), which includes sources such as lignite mining operations and lignite power plants that generate a high percentage of the energy in Greece; (2) the greater Athens area, the most populated area of the country; and (3) Thessaloniki, (4) Patra, and (5) Volos, three large cities in Greece. We defined extreme PM10 pollution episodes (EEs) as days during which PM10 concentrations at all five sites exceeded the European Union (EU) 24-hr PM10 standards. For each EE, we identified the corresponding prevailing synoptic and local meteorological conditions, including wind surface data, for the period from January 2009 through December 2011. We also analyzed data from remote sensing and model simulations. We recorded 14 EEs that occurred over 49 days and could be grouped into two categories: (1) Local Source Impact (LSI; 26 days, 53%) and (2) African Dust Impact (ADI; 23 days, 47%). Our analysis suggested that the contribution of local sources to ADI EEs was relatively small. LSI EEs were observed only in the cold season, whereas ADI EEs occurred throughout the year, with a higher frequency during the cold season. The EEs with the highest intensity were recorded during African dust intrusions. ADI episodes were found to contribute more than local sources in Greece, with ADI and LSI fraction contribution ranging from 1.1 to 3.10. The EE contribution during ADI fluctuated from 41 to 83 μg/m3, whereas during LSI it varied from 14 to 67 μg/m3. IMPLICATIONS:This paper examines the occurrence and nature of extreme PM10 pollution episodes (EEs) in Greece during a 3-yr period (2009-2011). Fourteen EEs were found of 49 days total duration, classified into two main categories: Local Source Impact (53%) and African Dust Impact (47%). All the above extreme PM10 air pollution episodes were the result of specific synoptic prevailing conditions. Specific information on the linkages between the synoptic weather patterns and PM10 concentrations could be used in the development of weather/health-warning system to alert the public that a synoptic episode is imminent.

The dispersion of air pollutants from multiple industrial stacks located in complex topography is an interesting subject. An attractive case is that of the wider region of Western Macedonia in NW Greece, where the greater amount of electric power of Greece is being produced by lignite power plant stations (LPPS). Considerable amounts of atmospheric pollutants are emitted by those LPPS into the atmosphere due to the quantities of coal burned. The variability of the topographic features and the terrain complexity of the area may lead to the formation of local atmospheric circulations of various types, which affect pollutant's transport and dispersion. In the present work, the dispersion conditions that favor the pollutants accumulation in the area are investigated. For this purpose, 1 year's hourly SO2 concentrations, surface wind measurements and a mesoscale meteorological and air pollution model (The Air Pollution Model, TAPM) were used. The SO2 and wind measurements were collected in situ from monitoring stations located nearby and at a greater distance from the power plants. Yearly and daily variations of SO2 concentrations are analyzed and discussed, and the period with the highest concentrations is selected. During this period, the evolution of the atmospheric boundary layer (ABL) in the area as well as the pollutants dispersion is examined. Statistical measures between modeled and observed meteorological data were in good agreement and a good correlation coefficient 0.68 and 0.98 was found in the SO2 variations. The analysis of the wind fields indicated better ventilation in the center of the area due to topographic venturi effects, while the dispersion mechanism which resulted in the relatively high ground level concentrations was fumigation. Finally, the evolution of the ABL was affected by the complex interactions between topography and mesoscale flows as it was found by the turbulent kinetic energy cross sections.

Many epidemiological studies have revealed consistent associations between ambient concentrations of inhalable (PM10) particles and their elemental composition with adverse respiratory health effects. On the other hand, suspended particulate matter emissions from several types of sources can be identified by the investigation of their particle element composition. The objectives of this work were to present the results of PM10 concentrations and trace elements obtained from 1year sampling/analysis campaign. Three different sampling sites of the region of Western Macedonia in Greece were selected to investigate the PM10-associated elements fingerprints in samples of airborne particles: S1 in the center of Kozani, where urban activities and traffic density occur, S2 in the city of Ptolemaida located close to the industrial area, and S3 in the village of Eratyra in a rural residential district. The PM10 samples were analyzed by ISP-MS instrument. Twenty five elements were detected at quantifiable concentrations in the examined PM samples. Finally, an attempt was made to identify the main PM10 sources that affect the sampling sites. For this purpose was applied the multivariate Positive Matrix Factorization (PMF) receptor model.

PM10 suspended particles were collected from the Kardia lignite mine (July 2009), the the campus of Technological Education Institution of Western Macedonia (December 2010) and the Kozani city centre (August 2005). The mineralogical composition and the amorphous materials content of the samples was determined by X-Ray Powder Diffraction method. All samples contain amorphous materials (43-66 wt.%), calcite (13-37 wt.%), micas + clays (4-9 wt.%) and quartz (2-8 wt.%), while in three samples feldspars (2-11 wt.%) were detected. Anhydrite, which is a constituent of the fly ash and the bottom ash, was detected (6 wt.%) only in one sample from the area of Kardia mine. Gypsum was detected, in the Kardia mine (2 and 3 wt.%), in the Kozani city centre (8 wt.%) and in the University campus (13 and 14 wt.%). Gypsum is a constituent of the mined lignite, the stack-gas ash and the Saharan dust. That explains the higher concentrations of gypsum in the University campus on 1 st and 2 nd of December 2010, where the influence of Saharan dust on the atmospheric particulate matter levels in Western Macedonia was reported.