Small scale structure in temperature and salinity near Timor and Mindanao

Abstract

For some time it has been known that continuous soundings of temperature and salinity as functions of depth in the main thermocline of the ocean have much complicated detail: small inversions, extrema, and indications of homogeneous regions separated by sharp gradients. On two occasions during the summer of 1965, closely-spaced stations were occupied in order to discover whether or not there is extensive spatial coherence horizontally in these features. It was found that they are in fact very thin horizontal laminae, extending from 2 to 20 kilometers horizontally, and from 2 to 40 meters vertically. After describing several different cases where the laminae are particularly clearly discernible, the implications of the structures in understanding the vertical mixing processes that occur in the ocean are explored. Estimates of the probable time scale and dissipation time of the laminae are made.