The angular distribution of radio waves partially reflected from the lower ionosphere

Radar measurements of aspect sensitivity of atmospheric scatterers using spaced-antenna correlation techniques

In order to balance the momentum budget of the mesosphere, it is necessary to have a source of momentum in that region to drive the observed meridional circulation. Thus measurements of mesospheric momentum flux are fundamental to our understanding of the dynamics of the mesosphere. The first measurements of momentum flux in this region did not adequately take into account the effect of aspect sensitivity on the effective pointing angle of a radar beam and were therefore incorrect by some factor. In this paper a method of determining the pointing direction of a radar beam from the spatial correlation function of the echoes is presented and applied to a data set that spans a year beginning in March 1985. Momentum fluxes during twelve 4-day periods thoughout the year are calculated using these improved pointing angle calculations and a new outlier rejection scheme. The results, representing a significant expansion of the worldwide mesospheric momentum flux data set, are then presented.

A Haug

Papers

An interpretation of asymmetric cross-correlation functions in D-and lower E-region drift measurements