METCRAX- The Meteor Crater Experiment: An upcoming Study of Cold Air Pools and Seiches in Arizona's Meteor Crater

A month-long meteorological field experiment is planned for October 2006 at the 1.2-km-wide, 175-m-deep Meteor Crater near Winslow, Arizona. The circularly symmetrical crater basin formed by the meteor impact provides a near-laboratory setting to study the structure and evolution of the stable boundary layer (SBL) within, above, and in the vicinity of the crater, including the effects of radiative and sensible heat flux divergences and slope flows on the heating and cooling of the crater's atmosphere. The uniform elevation ridgeline of the crater is expected to reduce large-scale advection into the closed basin under statically stable conditions, thus simplifying the mass and heat budgets for the atmospheric volume inside the crater.

The field measurements are designed to capture (a) the mean and turbulence characteristics of the down-slope and up-slope flows into and out of the crater, (b) the diurnal cycle of buildup and breakup of the cold-air pool, (c) seiches and other gravity waves, and (d) mesoscale variability of the ambient wind, which is expected to trigger seiches and waves within the basin. The observational program is being supported by in situ and remote sensing equipment from the National Center for Atmospheric Research's Earth Observing Laboratory, and will also include observations from tethered balloons, temperature data loggers and long- and short-wave radiation sensors. The observations and analyses will be supplemented with state-of-the-art Direct Numerical Simulations (DNS), Large Eddy Simulations (LES), and mesoscale model simulations. The proposed investigations are expected to have important practical benefits in air quality and frost forecasting, agricultural meteorology, and local weather prediction.

The poster will introduce the Meteor Crater and its topographical characteristics, outline the goals and objectives of the METCRAX meteorological experiments, and provide an overview of the instrumentation to be used and the experimental results to be expected.