Spatial interferometer applications to study PMSE and transient velocity features with the EISCAT VHF radar
Abstract
The EISCAT radars have been used intensively over the recent years to study the polar mesosphere summer echoes (PMSE). A summary of these observations was published by Roettger. Dynamical features in the PMSE can show quasi-sinusoidal gravity wave modulations as well as steepening, which is displayed in the Doppler spectra measured with vertically pointing antenna beam. This transient steepening was assumed to be related to the wind corners observed with chaff released from rockets. This steepening feature was so far only observed with VHF radar in the vertical velocity and further proof would be necessary to detect wind corner features also in the horizontal wind. The experiments described here provide this information by applying the spatial interferometer technique introduced to VHF radars by Roettger and Ierkic. We show that this transient steepening is consistent with spontaneous changes of vertical velocity and the horizontal velocity amplitude and direction, which is assumed as a sign of solitary waves. We, thus, have a proper means to study these non-linear processes also with MST radar in the mesopause region.
- Publication:
-
Solar-Terrestrial Energy Program: Proceedings of the 6th Workshop on Technical and Scientific Aspects of MST Radar
- Pub Date:
- August 1993
- Bibcode:
- 1993step.proc..289R
- Keywords:
-
- Antenna Radiation Patterns;
- Doppler Radar;
- Eiscat Radar System (Europe);
- Gravity Waves;
- Interferometers;
- Mesosphere;
- Meteorological Radar;
- Radar Echoes;
- Mesopause;
- Radar Beams;
- Solitary Waves;
- Summer;
- Very High Frequencies;
- Communications and Radar