基于拉曼激光雷达的南京上空大气温度廓线观测

介绍了综合使用瑞利、拉曼、米散射三种技术的激光雷达的基本结构与拉曼散射温度反演原理。对其中的拉曼回波信号进行了背景噪声扣除、滑动平均和小波变换降噪，在此基础上分析了气溶胶对拉曼激光雷达温度廓线反演的影响。利用上述激光雷达信号处理方法对南京上空的温度廓线进行观测，反演了2010年11月19日18时53分至19时35分连续观测的数据。反演的温度廓线表明，观测开始至观测结束，5.5 km处的温度变化为2 K的波动变化；对2010年11月整月的观测数据进行分析处理，得到11月份上中下三旬的平均温度廓线。在10 km高度处，下旬温度比上旬温度低4 K，随着入冬的进程，低空段的大气温度递减率有明显增大的趋势；11月的月平均温度在5~10 km处低于模式值4 K左右，并且两者几乎平行，说明11月份5~10 km各高度温度比模式均低4 K左右。

Measurement of Temperature Profiles above Nanjing Using Raman Lidar

The basic structure of Rayleigh-Raman-Mie (RRM) lidar as well as the principle of temperature retrieval algorithm using Raman scattering are introduced. Background correction, slide average and wavelet transform are employed to denoise the Raman backscattering signal, and then the effect of aerosols to temperature profile is analyzed. Using the algorithm described, temperature profiles above Nanjing from 5 km to 18 km during 1853 to 1935 on November 19, 2010 are retrieved. The measured results showed that the temperature variation at altitude of 5.5 km is less than 2 K; The entire month of observation data during November 2010 are analyzed and processed, average temperature profiles of three ten days are obtained. At altitude of 10 km, temperature of first ten days is 4 K higher than that of the third ten days. With winter approaching, the temperature lapse rate has significantly increased in low-altitude section. Monthly mean temperature in the range of 5~10 km is 4 K lower than the model value, and the two profiles are almost parallel which showed temperatures at most altitude below 10 km are 4 K lower than that of model.