Las Vegas Ozone Study TOPAZ Data
May 22, 2013
May 22. Wednesday. Clear in the morning with thick haze in the valley. Calm early, but the wind picked up in the afternoon becoming very strong (up to 28.4 m/s from the SSW) in the evening as the jet stream moving around an upper level trough passed overhead. Lee clouds formed to the east in the afternoon. Lidar data was collected from 0630 to 2210 PDT. The preliminary TOPAZ curtain plot shows 60-65 ppbv O3 below 1.4 km AGL in the morning, with 55-60 ppbv above. The cleaner air descended to the surface at about 1300 PDT with the in situ O3/CO concentrations dropping from 65/130 to 48/121 ppbv and the relative humidity dropped from 20 to 10%. This sequence was repeated in the afternoon and evening when the highest wind speeds were measured. The haze extended to Angel Peak in the afternoon.
Note: the low (purple) ozone values seen near the top of the curtain plot near midday are biased by the solar background in these preliminary analyses.
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