Physical variability in the sea and the consequences for fisheries hydrography

Abstract

Progress in fisheries hydrography depends on progress in the knowledge of physical and chemical variability in the sea. This variability is caused by short term changes in the fine structure of layering in temperature, salinity, current and chemical parameters and revealed by the new ways developed in instrumentation. Some examples of tlie results, achieved in the North Atlantic, the North Sea and the Baltic, are represented.