Estimations of the Optical Properties and Direct Radiative Forcing of Aerosol Chemical Components in PM2.5 Measured at Aewol Intensive Air Monitoring Site on Jeju Island

The optical properties and direct aerosol radiative forcing (DARF) of different aerosol components in $PM_{2.5}$ (water-soluble, insoluble, black carbon (BC), and sea-salt) were estimated using the hourly resolution data measured at Aewol intensive air monitoring site on Jeju Island during 2013, based on a modeling approach. In general, the water-soluble component was predominant over all other components with respect to its impact on the optical properties(except for absorbing BC) and DARF. The annual mean aerosol optical depth (AOD) at 500 nm for the water-soluble component was $0.14{\pm}0.14$ ($0.04{\pm}0.01$ for BC). The total DARF at the surface ($DARF_{SFC}$) and top of the atmosphere ($DARF_{TOA}$), and in the atmosphere ($DARF_{ATM}$) for most aerosol components(except for sea-salt) during the daytime were highest in spring and lowest in fall and/or summer. The maximum $DARF_{SFC}$ of most aerosol components occurred around noon (12:00~14:00 LST) during all seasons, while the maximum $DARF_{TOA}$ occurred in the afternoon (13:00~16:00 LST) during most seasons (except for spring). In addition, the estimated $DARF_{SFC}$ and $DARF_{ATM}$ of the water-soluble component were -20 to $-59W/m^2$ and +3.5 to $+14W/m^2$, respectively, while those of BC were -18 to $-29W/m^2$ and +23 to $+37W/m^2$, respectively.

제주 애월 대기오염집중측정소의 PM2.5 에어로졸 화학성분 자료를 이용한 광학특성 및 직접적 복사강제력 추정 연구