Table 1.
Statistics for diel-average tropospheric column mean OH (X[OH], 106 cm−3)
| Period | All X[OH] | NH X[OH] | SH X[OH] | NH/SH (global sOH) | NH/SH (best estimate)* |
| August | 1.02 ± 0.24 | 1.26 ± 0.29 | 0.81 ± 0.19 | 1.20 ± 0.06 | 1.26 ± 0.05 |
| February | 1.04 ± 0.25 | 0.88 ± 0.21 | 1.14 ± 0.28 | 0.57 ± 0.05 | 0.60 ± 0.04 |
| Average† | 0.97 ± 0.25 | 1.03 ± 0.26 | 0.92 ± 0.25 | 0.85 ± 0.08 | 0.89 ± 0.06 |
All averages are weighted by tropospheric column mass. Uncertainties are 1σ.
*
Weighted mean of NH/SH ratios calculated from X[OH] using a single value for sOH (this table) and hemisphere-dependent values (SI Appendix, Tables S2 and S3).
†
Gridded X[OH] is averaged over both missions before calculating statistics (Methods). Grid cells with missing X[OH] for one mission only are filled with 0 before averaging.