Μελέτη της συγκέντρωσης των αιωρούμενων σωματιδίων στο κέντρο της Θεσσαλονίκης

This undergraduate thesis examines the temporal evolution and behavior of particulate matter PM10 and PM2.5 in the urban area of Thessaloniki, based on air quality measurements from the Agia Sofia monitoring station for the period 2017-2024.The main objective of the thesis is the analysis of the concentration levels of the two pollutants, the investigation of their temporal and seasonal variability, the identification of exceedances of the established limit values, and the comparative assessment of the results.To achieve these objectives, a statistical analysis of the available dataset was performed, including the calculation of daily, monthly, and annual mean concentrations, as well as an examination of the distribution of pollutant levels by day of the week and hour of the day.The results were presented through appropriate graphical representations, which facilitated the identification of the dominant patterns governing concentration variability.The analysis reveals that both PM10 and PM2.5 exhibit pronounced temporal variability and a clear seasonal pattern, with higher concentrations observed during the cold period of the year.In the case of PM2.5, annual mean concentrations display an overall decreasing trend throughout the study period, declining from approximately 25 μg/m³ in the early years to around 16 μg/m³ by 2024.In the case of PM10, the annual averages of the same are near or exceeding the annual limit within the initial years and then gradually decrease.Daily the exceedance of the value of daily of PM10 (50 mg/m 3 ) is repeated, primarily in the winter seasons.The diurnal cycle is characteristic of the hourly analysis, with the primary peak in the evening hours during the cold season and the secondary peak in the morning hours at the beginning of the working day.Overall, the findings of this undergraduate thesis demonstrate that particulate matter air pollution in the city center of Thessaloniki represents a complex and dynamic phenomenon.