Measurements have been made to relate the acoustic fluctuations, resulting when a series of uniform sound pulses is transmitted through a medium in which there are random variations in space and time of the index of refraction, to the range from source to receiver, the acoustic frequency, and the parameters of the scattering medium. This paper considers the range dependence of the coefficient of variation (which is a measure of the acoustic fluctuations). A tank of water is heated from below causing the warmer, less dense, layers of water to rise by convection. This produces a medium of almost homogeneous turbulence with time and space variations in the temperature microstructure. Experimental results are in good agreement with a theory developed by Mintzer [J. Acoust. Soc. Am. 25, 922 (1953)] which predicts that the coefficient of variation of the acoustic pulses varies as the square root of range from source to receiver. There is some evidence that this dependence may be correct under broader conditions than are required by the theory.