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The optical properties and direct aerosol radiative forcing (DARF) of different aerosol components in PM2.5 (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 +/- 0.14 (0.04 +/- 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 similar to 14:00 LST) during all seasons, while the maximum DARF(TOA) occurred in the afternoon (13:00 similar to 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 -59 W/m(2) and +3.5 to +14 W/m(2), respectively, while those of BC were -18 to -29 W/m(2) and +23 to +37 W/m(2), respectively.

来源平台：JOURNAL OF KOREAN SOCIETY FOR ATMOSPHERIC ENVIRONMENT