Fig. 6: Wind-driven patterns and potential source contributions of aged biomass burning factors.
From: Online molecular insights into sources and formation of organic aerosol in Shanghai

Polar plots show estimated mass concentrations of a Aged BBOA1 and b Aged BBOA2 derived from Non-parametric Wind Regression (NWR). Concentration-Weighted Trajectory (CWT) results for hourly concentrations of c Aged BBOA1 and d Aged BBOA2. Wind speed units are km/h in (a, b).