Abstract
Mesurements of electron densities in the mesosphere at 43S (Christchurch, N. Z.) have shown that relatively constant values exist in summer, but large variations occur in winter. During the period 21–29 June 1963, isopleths of electron density descended and ascended by approximately 10 km, while stratospheric temperatures rose and fell by 10C. Both effects are ascribed to atmospheric vertical motion. This instance of “anomalous” ionospheric absorption shows the influence of circulation changes in redistributing photochemical constituents through the mesosphere.
