Combined satellite and ground monitoring of air pollution of Sofia, Bulgaria – Results and conclusions

• Main Author: Takuchev, Nikolay P.
• Format: Conference Proceeding
• Language: English
• Subjects: Air monitoring; Air pollution; Cities; Cyclones; Ground-based observation; Particulate emissions; Satellite observation; Solar magnetic field; Wind; Wind speed
• ISSN: 0094-243X; 1551-7616
• DOI: 10.1063/5.0173005

Introduction. Increased air pollution with particulate matter (PM) over several large cities in Western Bulgaria is observed during the heating season in the last few years. The country capital Sofia is also located in the western part of the country. The situation with the air pollution in Sofia is even more complicated because of its location in a valley, where often occur meteorological conditions, which lead to air pollution. Objective. A study was conducted to extract additional information about the history and dynamics of air pollution over the city of Sofia. A combined method was used – satellite and ground-based observations, covering the last 20 years (for some aspects of the research the data series were with 40 and more years scope). Material and methods. Data from satellite observations of the region of Sofia for the last 20 years, were extracted from NASA databases through the GIOVANNI interface. Ground data were received from the Bulgarian Executive Environment Agency (EEA) for five automatic monitoring stations, located in the city area. Results and conclusions. Increasing PM pollution over the Sofia region is due to meteorological reasons, not due to increased domestic combustion. The wind velocity in the area cyclically changes over 22 years period which is the period of cyclical change of cyclones passing over the Balkan Peninsula and is connected with their winds. For the last few years, the wind velocity cycle is at its minimum – relatively weak wind. A possible reason for the mentioned cycle is the cycle of the solar magnetic field, which has the same cycle period.