Characteristic Distributions of O3 at Taewha Research Forest near Seoul Metropolitan Area
Abstract:The measurements of O3, NOx, CO, and SO2 were conducted at 6 heights (4.1, 9.5, 15, 20, 31, 39 m) of 41 m tower at Mt. Taehwa, near Seoul metropolitan area (SMA) from 2011 to 2014. In addition, VOCs were measured seasonally for a short period using a PTR-QMS (Proton Transfer Reaction – Quadruple Mass Spectrometer).
In vertical distribution of O3, the mean concentration was slightly higher at 39 m (above canopy) than at 15 m (below canopy). Ozone reached the maximum and minimum concentration at 15:00 and 07:00, respectively. The monthly mean concentration of O3 was the highest in June, which was in accordance with the highest concentration of isoprene and monoterpenes and maximum PAR (Photosynthetically Active Radiation). NOx was transported from nearby highway mostly in the morning, which fueled O3 formation. At Taehwa Research Forest, it was well constrained the evolution of biogenic VOCs mixed with urban emission and their impact on O3.