Diurnal Cycle of Thermally Driven Cross-Basin Winds in Arizona's Meteor Crater

摘要

Cross-basin winds produced by asymmetric insolation of the crater sidewalls occur in Arizona's Meteor Crater on days with weak background winds. The diurnal cycle of the cross-basin winds is analyzed together with radiation, temperature, and pressuremeasurements at the crater sidewalls for a 1-month period. The asymmetric irradiation causes horizontal temperature and pressure gradients across the crater basin that drive the cross-basin winds near the crater floor. The horizontal temperature and pressure gradients and wind directions change as the sun moves across the sky, with easterly winds in the morning and westerly winds in the evening. A case study of 12 October 2006 further illustrates the obtained relation between these parameters for an individual day. The occurrence of an elevated cross-basin flow on 23 October 2006 is shown to relate to the presence of an elevated inversion layer.