Retrieval of temperature and humidity profiles from ground-based high-resolution infrared observations using an adaptive fast iterative algorithm

• DOI: 10.5194/amt-16-4101-2023
• Publication Date: 2023-09-11T12:47:37Z
• Authors: Wei Huang; Lei Liu; Bin Yang; Shuai Hu; Wanying Yang; Zhenfeng Li; Wantong Li; Xiaofan Yang
• Keywords: Earthwork. Foundations; TA715-787; 0207 environmental engineering; Environmental engineering; 02 engineering and technology; TA170-171

Abstract. Various retrieval algorithms have been developed for retrieving temperature and water vapor profiles from Atmospheric Emitted Radiance Interferometer (AERI) observations. The physical algorithm, named AERI Optimal Estimation (AERIoe), outperforms other in many aspects except the time, which is significantly increased due to complex radiative transfer process. calculation of Jacobian matrix most computationally intensive step algorithm. Interestingly, an analysis change observations' information content with respect Jacobians revealed that AERIoe algorithm's performance presents negligible dependence on these metrics. Thus, could remain unchanged when variation atmospheric state small process reduce time-consuming computation. On basis above findings, a fast physical–iterative algorithm was proposed by adaptively recalculating keeping changes state. Experiments synthetic observations demonstrate method experiences average reduction time impressive 59 % compared original while achieving maximum root-mean-square errors less than 0.95 K 0.22 log(ppmv) heights below 3 km profile, respectively. Further analyses fast-retrieval reached acceptable convergence rate 98.7 %, marginally lower AERIoe's 99.9 826 cases used this study.