Figure 3
From: Recent intensification of winter haze in China linked to foreign emissions and meteorology
Time series of standardized regional mean wind speed (black dashed lines, unitless) and local concentration efficiency of (a) sulfate, (b) POM and (c) BC (red dashed lines, μg m−3 Tg S−1 for sulfate and μg m−3 Tg C−1 for POM and BC) for the North China Plain emission. (d) Standardized wind speed derived from MERRA reanalysis used for wind nudging in this study, ECMWF reanalysis and NCEP/NCAR reanalysis data. Solid lines represent five-year moving averages. Temporal correlation coefficient (R) between unsmoothed aerosol concentration efficiency and standardized wind speed is shown at the top-right corner of panel a, b and c.
