Fingerprint of transported smoke from 2023 wildfires in Greece on aerosol optical properties

Abstract

Wildfires represent a growing global environmental challenge, and the 2023 fire season in Alexandroupolis, Greece, marked a significant event. This study analyzes columnar aerosol optical properties during this wildfire and a Saharan dust intrusion, and compares them with the 2021 Athens wildfires. Results reveal a peak in aerosol concentration in Thessaloniki during August 23, with an aerosol optical depth (AOD) at 440 nm of 2.8. The Angstrom exponent (AE) at 440-870 nm reaches values of 2.2, indicating small sized particles with higher absorption at longer wavelengths. The Saharan dust event on August 18 exhibits small AE values (0.1 to 0.5) due to coarser particles, which have higher absorption at shorter wavelengths. Changes in columnar optical aerosol parameters were similar to those of 2021 with slight differences in particle size. This study shows the influence of medium range transport of aerosols from wildfires affecting air quality.