Fig. 1. Background field error covariance matrix

Fig. 2. Jacobian weight function diagram for 7 channels

Fig. 3. Average RBT of oxygen in 200 water vapor channels

Fig. 4. Square of root mean square error of RBT of oxygen in 200 water vapor channels

Fig. 5. Information content distribution of candidate channels

Fig. 6. Accumulated information content

Fig. 7. Information content of 200 channels and 7 channels of RPG-HATRPO-G3

Fig. 8. Information content distributions of 200 channels in condition 1 and condition 2

Fig. 9. Information content distributions of 200 channels in condition 3 and condition 4

Fig. 10. Information content distributions of 200 channels when the square root of the observed error root mean square error is 0.2 K2 and 0.4 K2, respectively

Fig. 11. Flow chart of simulation

Fig. 12. Downward RBT. (a) 200 channels; (b) 7 channels

Fig. 13. Inversion deviation at different heights under different number of channels

Fig. 14. Inversion deviation of different channels