A four-year research program is proposed to investigate downslope-windstorm-type flows (DWF) that have important societal effects and are poorly understood scientifically. The program includes a one-month field program at Arizona's Barringer Meteorite Crater and simulations with a Large-Eddy-Simulation (LES) model. A serendipitous discovery in a prior NSF-funded research program identified this location as being ideally suited for such a study, as DWFs develop there regularly when thermally driven drainage flows cascade over the craters rim on clear, undisturbed nights. The craters rim and environs are on a scale that can be readily instrumented to investigate these flows and the changing upstream conditions that cause them to form. DWFs are produced intermittently on the upwind inner sidewall of the small, circular crater basin as pulsations occur in the temperature and wind profiles of the approaching flow. This proposal calls for the first systematic investigation of DWFs at a location where many replications will occur naturally. The field campaign will be conducted in October 2013 to collect data sets uniquely suited to support analyses to answer extant scientific questions about atmospheric DWFs produced by density-stratified flow over topography. Multiple LiDARs, SoDARs, and tethered balloon sounding systems, as well as infrared time-lapse cameras and surface-based meteorological instrumentation will be used to collect the necessary data. The goal of the field research, analysis, and LES model simulations is to determine the characteristic atmospheric structure and evolution associated with the DWFs, the controlling parameters in the katabatic winds that drive DWFs and, through the modeling studies, extend the findings to basins and ridges of different size and shape to gain a more general understanding of DWFs. Novel and innovative concepts are featured in the proposal, with analyses and modeling informed by field experience, a short climatology, and our initial analyses and model simulations.
|Effective start/end date||9/1/12 → 8/31/14|
- National Science Foundation (NSF): $154,594.00