Other previous studies have investigated the influence of regional and long‐range transport of carbonaceous aerosols in eastern Asia and surrounding downwind area [Mader et al., 2002; Chan et al., 2003, Han et al., 2008a]. Cheng et al. [2006] carried out a continuous measurement on BC from June 2004 to May 2005 at Hok Tsui, a site located downward of East Asia, and investigated the influence of southward outflow of continental pollution.