Proceedings with Extended Abstracts (single PDF file) - Radio ...

paper was a poster paper, I.3.305, given by Meek, who examined the distribution of largewind speeds measured by FCA methods in the upper atmosphere. Traditionally thesewinds are rejected in FCA analysis, but Meek wondered about the fact that they could bereal, and possibly the radar was able to see through the E-region to higher heights onoccasion.Haldoupis and Pancheva, in a departure from studies exclusively of the neutral atmosphere,examined the impact of neutral winds on determination of sporadic E layers in theionosphere. Evidence for strong planetary wave modulation was especially noted. Nonlinearinteractions were also investigated.Gravity Waves.The session then turned to discussions about gravity waves. It began with an overview byGavrilov, who discussed a variety of measurements by both radar and non-radar techniques.A possible correlation between El Nino and gravity wave activity in the upper atmospherewas noted. Pavelin and Whiteway looked at the importance of mountain waves, and howthey interact with other waves. One wave could often act to produce a critical layer foranother wave. A series of papers then followed relating to gravity wave observations withthe Indian MST radar, including papers by Rao, Reddy, Kamala, Kumar and colleagues.Roettger et al. examined relationships between deep convection and wave generation withthe Chung-Li radar. A potential relationship with ionospheric spread-F was noted.One paper also examined lidar observations of gravity waves (I.3.508), and Riggin andZhou discussed measurements of gravity wave momentum fluxes using a dual beam radarat Arecibo (poster paper I.3.502).Interaction between Turbulence and Radio Waves.The topic of discussion then turned to turbulence. To begin, two presentations were givenrelating directly to the relationship between radio waves and turbulence. David Fritts gavea presentation on behalf of Patricia Franke which showed how a computer model was to beused to simulate radio wave scatter from turbulence. Turbulence would be generated downto scales of about 10 metres or less, and then a realistic radio-wave spectrum was to be“transmitted” into the region, and radio backscatter was to be recorded. Use of a PML(perfectly matched layer) at the top of the model, to produce spurious radiowavereflections, was discussed.Following this, Kudeki discussed how he had used high resolution radar observations tostudy fine scale structure of turbulent layers. This was paper I.3.37, which was given out oforder, but fitted into the program better at this point. Then Lehmacher et al. (paper I.3.24)presented a follow-up paper which also looked at fine-scale structure in the mesosphere at150 meter resolution.24