The properties of summer radiation and aerosols were studied at Xinzhou, a suburban site on the North China Plain (NCP) by using ground-based measurements in 2014. The radiation detections under clear and cloudy skies showed that longwave radiation presented a sigmate pattern, with a maximum of 392.6 W m(-2) at 1700 local standard time (LST) associated with the cloud radiative forcing, and a minimum of 360.0 W m(-2) at 0600 LST when the lowest surface temperature (17.1 degrees C) occurred. Solar radiation, including global, direct, diffuse, photosynthetically active, ultraviolet-A, and ultraviolet-B, exhibited a single peak at similar to 1300 LST. A bimodal size distribution, with fine mode aerosols showing a peak between 0.1 and 0.2 mu m and coarse mode aerosols showing a peak at similar to 5 mu m, was observed at Xinzhou. The dominant aerosol type was black carbon coating on coarse particles (85.7%) for the cases with aerosol optical depth at 400 nm (AOD) greater than 0.4, leading to a lower single scattering albedo (0.81) than the typical value (similar to 0.90) at the other stations on the NCP. The mean values of EAE and AAE (extinction and absorption angstrom ngstrom exponent, respectively) were 1.14 +/- 0.15 and 0.58 +/- 0.28 for the aerosol measurements. The average of instantaneous aerosol direct radiative forcing at the bottom of the atmosphere was -138.9 +/- 33.0 W m(-2)for the cases with AOD > 0.4. The results in this study are expected to improve understanding at suburban sites on the NCP of aerosol properties and their impacts on regional radiation budgets.
