Investigating the Structure of Tornadoes and the Near-tornado Environment Using Mobile High-frequency Ka-band Doppler Radar Technology

Texas Tech University, Lubbock TX

Investigators

Abstract

The intellectual merit of this study will be in the introduction of high frequency mobile Doppler radar technology to the VORTEX 2 field program. This is a large field program entering its second field operations period in May-June 2010 involving multiple mobile platforms focused on the study of tornadic thunderstorms in the upper Great Plains region. This contribution to the field program will involve two Texas Tech University Ka-band (35 GHz) (TTUKa) radars. Observations with these radars will be used to address many VORTEX 2 objectives related to better understanding the nature of circulations in the near-tornado environment, in tornado cyclones, and in sub-tornado-scale vortices. Owing to the use of non-linear pulse compression, a first for mobile high-frequency radar, these radar systems feature higher sensitivity than other such radars. The fine angular resolution and high sensitivity of the TTUKa radars will provide previously unresolved detail and coverage of air motions at the tornado scale. Two primary observational objectives are (1) horizontal and vertical structure of tornado vortices, and (2) pre-existing vertical vorticity maxima prior to tornadogenesis. The broader impacts of the study will be manifested in several ways. Graduate and undergraduate students will be heavily utilized in the planning and execution of TTUKa data collection and the presentation of preliminary results at mission briefings. Some of these students have a background in fields other than meteorology (e.g., civil engineering, wind engineering, mathematics), and therefore have the opportunity to expand their knowledge base. Given the typical ethnic diversity of the student population at Texas Tech University, traditionally underrepresented groups will have the opportunity to contribute to the project, particularly those of Hispanic descent. One ultimate goal of the proposed research is the improved understanding of tornado vortex structure, leading to advancement in understanding of hazards due to tornados. Another objective of the research is to improve tornado forecasts through the recognition of the influence of detectable variability in the pre-tornadic supercell environment on subsequent storm evolution. This increase in forecast skill is vital for the protection of life and property. Through the broad dissemination of research results in journal publications and conference presentations, all research objectives that are met will have significant impact in the community.