Distributed Feedback Interband Cascade Laser Based Laser Heterodyne Radiometer for Column Density of HDO and CH4 Measurements at Dunhuang, Northwest of China

Remote sensing of HDO and CH4 could provide valuable information on environmental climatological studies. In a recent contribution, we reported 3.53 μm distributed feedback (DFB) inter-band cascade laser (ICL)-based heterodyne radiometer. the present work, details measurements inversions at Dunhuang, Northwest China. The instrument line shape (ILS) radiometer (LHR) is discussed firstly, spectral resolution about 0.004 cm−1 theoretically according to ILS. Furthermore, retrieval algorithm, optimal estimation method (OEM), combined with LBLRTM (Line-by-line Radiative Transfer Model) for retrieving densities atmospheric are investigated. were retrieved be less than 1.0 ppmv, while around 1.79 ppmv from 20 24 July 2018. correlation coefficient water vapor by LHR EM27/SUN 0.6, potential reasons differences discussed. Finally, in order better understand procedure, Jacobian value Averaging Kernels also