CONFLUENCE THEORY OF THE HIGH TROPOSPHERIC JET STREAM

Abstract

In 1947 a suggestion was made by one of the authors that the existence of fast narrow currents in the upper troposphere was due to the bringing together, or confluence, of warm and cold air masses from northerly and southerly regions. In the present paper an attempt is made to extend this theory by a somewhat more detailed examination of the dynamics of confluence. It is suggested that the energy of the jet is derived from a direct transformation of potential into kinetic energy. This source of energy is independent of stability in the usual sense, a fact which may be of some importance in understanding the general circulation. A comparison is made between this theory and the known behavior of the jet stream. Here extensive use is made of recent synoptic studies by Palmén and his co-workers and of charts showing the normal appearance of the hemispheric jet stream (which are shown for the first time). It is concluded that these observational studies tend to confirm the theory of confluence.