Figure 2. Left panel: latitudinal dependence of the TSI to TI ratio in bulk aerosol (red boxes), in the fine PM1fraction (blue) and the coarse fraction (yelow). Right panel: statistics of the TSI/TI ratio in bulk aerosol. The box and whiskers plot statistics are: interquartile range (box), 1.5 × interquartile range (whiskers), median (horizontal line), mean (square) and outliers (diamonds). The circle indicates the TSI fraction derived from the slope of the TI vs TSI error-weighted linear fit (Gómez Martín et al., 2021). The number of samples are indicated below the boxes.
Figure 2 does not show clear latitudinal trends in the bulk TSI/TI ratio. However, lower values were measured in some campaigns at high latitudes (C5, C7 and S35), and higher values in the tropical Atlantic (C12). Figure S3 shows TSI/TI in bulk aerosol as a function of longitude, for a zonal band between 55°S and 55°N. The campaigns in the Atlantic reporting both TI and TSI show TSI/TI ratios close to 90%-100%, while in the Eastern Indian - Western Pacific the ratio is closer to ~70%.