Troposphere–Stratosphere (Surface–55 km) Monthly Winter General Circulation Statistics for the Northern Hemisphere—Interannual Variations

Abstract

Individual monthly mean general circulation statistics for the Northern Hemisphere winters of 1978–79, 1979–80, 1980–81, and 1981–82 are examined for the altitude region from the earth's surface to 55 km. Substantial interannual variability is found in the mean zonal geostrophic wind; planetary waves with zonal wavenumber one and two; the heat and momentum fluxes; and the divergence of the Eliassen–Palm flux. These results are compared with previous studies by other workers. This variability in the monthly means is examined further by looking at both time-latitude sections at constant pressure levels and time-height sections at constant latitudes. The implications of this interannual variability for verifying models and interpreting observations are discussed.