Preliminary multiheight radar observations of waves and winds in the mesosphere over Jicamarca

Abstract

The Jicamarca Radio Observatory receives strong radar echoes from the mesosphere. This paper reports preliminary results of simultaneous measurements of echo power, radial velocity, and spectral width at 12 mesospheric heights spaced at 2.5 km intervals over the 60–90 km region. These results indicate that the echoing regions are not continuous in space; on time scales of an hour strong echoes tend to be received from well defined heights. Velocity oscillations are highly correlated at nearby altitudes, while velocities at altitudes separated by more than 5 km show little or no correlation. There is no clear upward or downward wave-like progression in either the velocities or echo power; rather, the dominant periodicities of the oscillations are observed to change with altitude. Correlations between the velocity of the medium, the echo power, and the spectral width at gravity wave time scales point to short period gravity waves as an energy source for turbulence at mesospheric altitudes.