为了实现大尺度区域下大气中水汽浓度的高灵敏度、 高精确性、 快速响应检测, 与遥感反演的数据进行校正, 采用了TDLAS直接吸收技术结合开放式监测的方法。 选择水汽分子在1.27 μm附近的单根吸收谱线为目标谱线, 设计了大尺度区域水汽激光检测系统。 结合多次反射池验证了系统性能, 40 m光程下极限灵敏度为14.803 mmol·mol-1。 利用本系统在中国科学院禹城综合试验站完成了1 420 m光程下的连续外场实验, 系统工作稳定, 并与同场地涡度相关观测系统中的气体分析仪LI-7500的测量数据进行了对比, 数据一致性较好。 为在复杂野外非均匀下垫面的水汽浓度变化的监测提供新方法。

Water vapor is an important meteorological parameter in the atmosphere, TDLAS direct absorption technology combined with open-path monitoring was used in order to achieve large-scale regional atmospheric water vapor concentration detection with high sensitivity, high accuracy and fast response, and to correct the remote sensing data. The large-scale regional laser detection system for water vapor was designed and the absorption line of water vapor molecules near 1.27 μm was chosen as the goal line. The system performance was verified in conjunction with a multiple reflection cell, that the system limit sensitivity was 14.803 mmol·mol-1 in optical path of 40 m. The continuous field experiment in 1 420 m optical path at the Yucheng Integrated Experimental Station, CAS was completed with this system which worked stably. Then the measured data was compared with the data of a gas analyzer LI-7500 in eddy correlation observation system at the same site, and the data consistency was good. A new method for water vapor concentration monitoring in the complex field of non-uniform underlying surface was provided.