Ristovski, Zoran, Wardoyo, Arinto Y. P., Morawska, Lidia, Jamriska, Milan, Carr, Stephen, and Johnson, Graham R. (2010) conducted airborne measurements of particle number concentrations and size distributions in the Northern Territory, Australia, during the early and late dry seasons of 2003. The study aimed to understand how biomass burning affects particle characteristics in different atmospheric layers, including the lower boundary layer (LBL), upper boundary layer (UBL), and free troposphere (FT). During the early dry season (June), particle concentrations were lower than during the late dry season (September). In June, concentrations were (685 ± 245) particles/cm³ in the LBL, (365 ± 183) particles/cm³ in the UBL, and (495 ± 45) particles/cm³ in the FT. In September, concentrations were (1233 ± 274) particles/cm³ in the LBL, (651 ± 68) particles/cm³ in the UBL, and (568 ± 70) particles/cm³ in the FT. Particle size distributions showed no significant change in the LBL and UBL, suggesting some penetration of biomass burning particles into the UBL. In the FT, particle concentrations and sizes were similar in both campaigns. The study found that particle concentrations decreased with altitude in the early dry season but increased in the late dry season, indicating longer exposure of plumes to atmospheric processes. The average particle concentration in the LBL was higher in September than in June, with a significant difference except between 850-1000 m. The CMD (count median diameter) was smaller in June than in September, indicating fresher smoke particles in June and aged particles in September. The study also found that particle concentrations in the FT were similar in both campaigns, suggesting long-range transport or sulfuric acid condensation as sources. The origin of the air masses was from marine sectors, with biomass burning significantly increasing particle concentrations. The findings highlight the impact of biomass burning on atmospheric particle characteristics and the importance of understanding these processes for climate modeling and environmental management.Ristovski, Zoran, Wardoyo, Arinto Y. P., Morawska, Lidia, Jamriska, Milan, Carr, Stephen, and Johnson, Graham R. (2010) conducted airborne measurements of particle number concentrations and size distributions in the Northern Territory, Australia, during the early and late dry seasons of 2003. The study aimed to understand how biomass burning affects particle characteristics in different atmospheric layers, including the lower boundary layer (LBL), upper boundary layer (UBL), and free troposphere (FT). During the early dry season (June), particle concentrations were lower than during the late dry season (September). In June, concentrations were (685 ± 245) particles/cm³ in the LBL, (365 ± 183) particles/cm³ in the UBL, and (495 ± 45) particles/cm³ in the FT. In September, concentrations were (1233 ± 274) particles/cm³ in the LBL, (651 ± 68) particles/cm³ in the UBL, and (568 ± 70) particles/cm³ in the FT. Particle size distributions showed no significant change in the LBL and UBL, suggesting some penetration of biomass burning particles into the UBL. In the FT, particle concentrations and sizes were similar in both campaigns. The study found that particle concentrations decreased with altitude in the early dry season but increased in the late dry season, indicating longer exposure of plumes to atmospheric processes. The average particle concentration in the LBL was higher in September than in June, with a significant difference except between 850-1000 m. The CMD (count median diameter) was smaller in June than in September, indicating fresher smoke particles in June and aged particles in September. The study also found that particle concentrations in the FT were similar in both campaigns, suggesting long-range transport or sulfuric acid condensation as sources. The origin of the air masses was from marine sectors, with biomass burning significantly increasing particle concentrations. The findings highlight the impact of biomass burning on atmospheric particle characteristics and the importance of understanding these processes for climate modeling and environmental management.