Measurements of the vertical-path atmospheric modulation transfer function (MTF) have been completed at both desert and mountain locations for daytime and nighttime conditions. The average atmospheric MTF characterized by the parameter r0 is found to be virtually identical, 34 mm, for both the desert and the mountain locations during the day, whereas a ratio of 1.7 is observed at night, 47 mm versus 82 mm, respectively. Relative peaks in r0 for both the mountain and the desert sites corresponding to the daily air-surface temperature crossover periods are observed. By collecting data at both 2 and 8 m above the desert surface, the effects of tower height are investigated.
D. L. Walters, "Atmospheric modulation transfer function for desert and mountain locations: r0 measurements," J. Opt. Soc. Am. 71, 406-409 (1981)