Abstract
Hadley circulations in a shallow fluid layer driven by a radial temperature gradient in the bottom plate have been investigated experimentally. The temperature on top of the fluid was uniform, and the vertical temperature gradient in the fluid was usually stable over the entire layer. The apparatus was either rotating or nonrotating. In the cast of stable stratification, axisymmetric one-loop circulations have been observed in the nonrotating as well as in the rotating case, in agreement with the classical concept of the Hadley circulation. In the nonrotating case with partially unstable stratification the flow was striated with jet of fluid moving rapidly to the center. In the corresponding rotating case the striations were spirals. In the parameter range of the experiments no example of azimuthal waves has been observed.
