ZWD analysis Nevada Hongkong UK

Analysis and figure-generation code for the study of a structure–amplitude relaxation precursor to convective initiation in GNSS zenith wet delay. From the wet delay we estimate two channels: a structure scale (λ, the spectral cutoff; smaller λ means longer, more coherent moisture structures) and an amplitude (σ). At rest the two are anti-correlated, and this coupling relaxes in the hours before convection. The repository contains the spectral estimator, the relaxation and temporal-lead tests, the coupled-fluctuation model, and the scripts that reproduce every figure, applied to three GNSS networks in contrasting regimes: continental (central United States), frontal-maritime (British Isles), and tropical (Hong Kong). Raw observations are not redistributed; only the derived structure-scale and amplitude products needed to reproduce the figures are included. Code under MIT, derived data under CC-BY-4.0.