Internal Waves in the Sea

Abstract

IN making the statement on page 592, to which Prof. Ekman refers, "that the first observations of short-period variations which indicated the existence of internal waves were discussed by Helland-Hansen and Nansen (1909) ", the authors have in mind the short-period variations observed during the 1893–96 voyage of the Fram. Nansen realized that they might be due to waves at the boundary between water-strata of different density, but it was not until 1909 that he and Helland-Hansen, persuaded by their 1900–4 observations in the Norwegian Sea, were convinced of the reality of internal waves.