SURFACE SIGNS OF THE BIENNIAL ATMOSPHERIC PULSE

Abstract
Further evidence is presented for the presence of a persistent periodicity somewhat in excess of 2 years duration. Its existence can be shown in the surface temperature at widely separated stations along two meridians from Norway to South Africa and from Canada to Cape Horn. Time series analysis by means of a narrow band-pass filter indicates phase relations among the stations, the most important of these being that the intertropical regions appear to be mutually in phase and that the higher-latitude stations are out of phase with the tropical stations. In the Northern Hemisphere, at extratropical stations, the amplitudes of the pulse are largest when the pulse extremes coincide with the winter months.