The role of near-surface temperature data sets in Terrain-Induced Rotor Experiment (T-REX) analyses

As part of the Terrain-Induced Rotor Experiment (T-REX), fifty-one temperature data loggers were deployed on the valley floor and sidewalls of the Owens Valley in March and April 2006. The loggers were spaced at 50-m altitude intervals on lines running up the Sierras on the west side of the valley and up the Inyo-White Mountains on the east side of the valley, and at approximately 10-km intervals on the valley floor along the Owens River between Lone Pine and Bishop, California. The loggers were programmed to take temperature observations every 5 minutes. These near-surface temperature observations were supplemented with twice-daily rawinsondes that were launched from the floor of the valley at 06 and 15 PST every day during the two-month experiment to characterize the valley atmosphere on the same cross-section as the main data logger lines.

Analyses of the temperature data logger and rawinsonde data will be focused on gaining answers to three questions - (1) Under what conditions do lines of temperature data loggers on the sidewalls provide a good proxy for free air soundings in the deep, 25-km wide valley? (2) How do surface temperatures vary in the along-valley direction and how does this variation relate to surface characteristics, diurnal wind systems and the presence or absence of strong downslope wind events? (3) Can these data, when combined with pressure data, provide surface potential temperature fields that are useful in visualizing cross-valley flow structures in mountain wave and rotor conditions? This abstract is being written before the T-REX experiments are concluded; the proposed poster will provide information on the quality of the data sets and offer initial answers to one or more of the above research questions, depending on research progress.