Fig. 1. Pure rotational Raman spectrum of N₂ and O₂

Fig. 2. (a) Ratio of rotational Raman echo signal intensities ; (b) Comparison of statistical temperature uncertainty between 532 nm and 354.8 nm Raman lidar systems （a）转动拉曼回波信号强度之比 ；（b） 532 nm和354.8 nm拉曼激光雷达系统温度不确定度的比较

Fig. 3. Light path diagram of the Raman lidar system

Fig. 4. Temperature sensitivity of pure rotational Raman signals

Fig. 5. Statistical temperature uncertainty versus filter center wavelength for different filter bandwidth in the daytime. (a) Δλ1=Δλ2=0.1 nm; (b) Δλ1=Δλ2=0.3 nm; (c) Δλ1=0.3 nm, Δλ2=0.5 nm; (d) Δλ1=0.3 nm, Δλ2=0.8 nm

Fig. 6. Statistical temperature uncertainty versus filter center wavelengths. (a), (b) Contour map of the variation of the statistical temperature uncertainty in daytime and nighttime detection with central wavelength CWL1 and CWL2; (c), (d) CWL1 takes a fixed value, the statistical temperature uncertainty changes with CWL2 in daytime and nighttime; (e), (f) CWL2 takes a fixed value, the statistical temperature uncertainty changes with CWL1 in daytime and nighttime

Fig. 7. Contour map of statistical temperature uncertainty varying with optical density

Fig. 8. (a) Statistical temperature uncertainty; (b) Statistical error of water vapor mixing ratio in the daytime