Oscillatory Motions in the Nonconvective Layer of a Solar Pond

Temperature oscillations in the nonconvective layers of the Na Cl solar pond of the University of New Mexico have been observed. These oscillations, which appear during the day and early in the evening, are correlated with the flux of solar energy in these regions. The period varies from 90 s up to 400 s, depending on the depth, and the amplitude can be as large as 1.4°C. The phenomena observed are conjectured to overstable oscillations predicted from double diffusive convection theory.