Classic imaging systems may experience deleterious effects of optical turbulence, leading to their quality degradation induced by image jitter and blur. Using a recently introduced model for the refractive index power spectrum of natural water turbulence accounting for average temperature in the range of 0°-30°C and average salinity concentration in NaCl in the range of 0-40 ppt, we derive expressions for turbulence-induced modulation transfer functions. Our analysis indicates that the imaging systems are very sensitive not only to the variance of fluctuations in these parameters but also to their average values. Our results are essential for underwater optical engineering, providing regional and seasonal variations in optical turbulence.
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