Fig. 2: Year-round variability of mass concentration and carbon isotopic composition of oxalic acid at the Heshan city.
From: Large contribution of fossil-derived components to aqueous secondary organic aerosols in China
The unshaded periods represent coastal background air mass regime, while the shadowed periods represent continental outflow air mass regime. Red and blue bars represent the concentration of oxalic acid during coastal background air mass regime and continental outflow air mass regime, respectively. The orange and green symbols show the δ13C composition and 14C-based fraction of non-fossil for oxalic acid.
