Taylor’s Frozen Turbulence Hypothesis (TFTH) has been used extensively in theoretical studies to model the temporal fluctuations of optical quantities affected by atmospheric turbulence. It has been relied upon to provide temporal-frequency spectra under varying propagation conditions and for different atmospheric refractive index models. However, experimental works have revealed its limitations, such as systematic inaccuracies in estimating cross winds during calm nights in scintillation measurements at astronomical sites, scintillation discrepancies in ground-layer measurements, and broad estimates of the coherence time in phase fluctuation measurement techniques. This highlights the need to recognize the limitations of the TFTH and seek alternatives that can provide a more reliable description of atmospheric turbulence’s temporal fluctuations. Here, we propose a spatio-temporal statistics for refractive index fluctuations through fluid dynamics models and evaluate the complex phase propagation under weak turbulence. Then, we test its ability to reproduce experimental observations under different ground-layer turbulence conditions.
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