AAAR 34th Annual Conference
October 12 - October 16, 2015
Hyatt Regency
Minneapolis, Minnesota, USA
Abstract View
Particle Burst and Growth Observed from a PAM Reactor at Taehwa Forest Observatory
XIAONA SHANG, Eunha Kang, Hyunjin An, Meehye Lee, William Brune, Korea University, South Korea
Abstract Number: 371 Working Group: Primary and Secondary Aerosols from Agricultural Operations
Abstract A Potential Aerosol Mass (PAM) reactor was coupled with a Scanning Mobility Particle Sizer (SMPS) and measurements were made at Taehwa forest observatory near Seoul metropolitan area, South Korea in April, May, and Oct., 2014. Secondary aerosol forming potential was investigated by comparing the particulate number and mass difference in PAM and ambient air, modulated every six minutes. In PAM reactor, SO2 was enough to produce new particles, of which number concentration was over 10^4 cm^-3 in nucleation mode. For PAM aerosols, the mass increase in nucleation and Aitken mode was comparable to mass loss in condensation mode. In ambient air, two types of particle bursts were distinct in the morning and afternoon. While the former was coincident with EC peak and regularly observed in the morning, the latter took place in the afternoon and lasted for several hours. The mode of morning burst was 20 ~ 30 nm, which is believed to be soot particles emitted from cars. In contrast, the particles of ~10 nm grew to ~40 nm with 3 ~ 4 hours in the afternoon, during which isoprene increased and reached the maximum.