NEW THEORY PROPOSED

Press, Volume CII, Issue 30288, 14 November 1963, Page 26

NEW THEORY PROPOSED

Circulation Of Atmosphere A theory linking the planetary circulation of the upper atmosphere with the ionisation at similar levels, and so with seasonal changes in short-wave radio reception, has been worked out by members of the Geophysical Observatory of the Department of Scientific and Industrial Research. A member of the observatory staff, Mr G. A. M. King, says this is the first time a satisfactory theory has been proposed to connect meteorological and ionospheric observations.

According to the theory, the main component of the planetary circulation above the mesopause (a temperature minimum at about 80 kilometres up) is a strong movement of air from the summer polar regions into the winter hemisphere. The basis of the theory is that a system of high-level winds affects the proportion of neutral atoms to molecules, especially as between, various latitudes. This in turn affects the recombination rate of electrons and ions. lonospheric evidence in support of the theory includes the progressivelylower frequency at which radio waves escape through the ionosphere as one moves from the winter hemisphere towards the summer pole. On the meteorological side, proof is not the direct concern of the observatory, but observations of sudden changes in stratospheric temperatures over the Antarctic with the onset of spring have been co-related with similarly swift changes in ionospheric radio-wave reflections.