A Novel Method for Boundary Value Determination in the Fernald Inversion for Horizontal Lidar Measurements

In the conventional Fernald inversion, the boundary value at the calibration point is commonly estimated using a slope-based method. This procedure increases algorithmic complexity and can introduce retrieval errors. Here, we propose an alternative boundary-value determination scheme that exploits the tendency of the Fernald forward-integration equation to diverge. Simulation experiments show that the proposed scheme is more stable than the slope method under atmospheric inhomogeneity and measurement noise. We further applied the method to horizontal lidar scans acquired in Lankao (Henan Province, China), capturing a regional pollution transport and dispersion episode. Together, these results suggest that the method enables real-time monitoring of the horizontal distribution of regional pollutants.