Abstract. Recently, there has been increasing interest in the relation between particulate matter (PM) pollution and atmospheric-boundary-layer (ABL) structure. This study aimed to qualitatively assess the interaction between PM and ABL structure in essence and further quantitatively estimate
aerosol radiative forcing (ARF) effects on the ABL structure. Multi-period
comparative analysis indicated that the key to determining whether haze
outbreak or dissipation occurs is whether the ABL structure satisfies the
relevant conditions. However, the ABL structure change was in turn highly
related to the PM level and ARF. |SFC−ATM| (SFC and ATM are
the ARFs at the surface and interior of the atmospheric column,
respectively) is the absolute difference between ground and atmosphere layer ARFs, and the |SFC−ATM| change is linearly related to the PM concentrations. However, the influence of ARF on the boundary layer
structure is nonlinear. With increasing |SFC−ATM|, the turbulence
kinetic energy (TKE)
level exponentially decreased, which was notable in the lower layers or ABL, but disappeared at high altitudes or above the ABL. Moreover, the ARF effects
threshold on the ABL structure was determined for the first time, namely
once |SFC−ATM| exceeded ∼55 W m−2, the ABL structure tends to quickly stabilize and thereafter change little
with increasing ARF. The threshold of the ARF effects on the boundary layer
structure could provide useful information for relevant atmospheric-environment improvement measures and policies, such as formulating phased
air pollution control objectives.