TOPAZ Data

July 21, 2016

< Previous Day | Archive Calendar | Next Day >

Daily Summary:

Thursday, July 21: CABOTS IOP2
Day 4 of CABOTS IOP 2 observations. TOPAZ data were taken from 10:57 to 19:05 PDT. AJAX spiral and missed approach near 14:00 PDT. Mostly clear all day with scattered altocumulus in the morning. Poor visibility in the morning that improved somewhat in the afternoon. High of about 37 C with southerly winds in the morning rotating to the northwest in the afternoon. The lidar measurements were very similar to the previous day with an elevated layer (EL) of enhanced ozone and aerosol above the boundary layer (BL). The EL was lower (800-1300 m) than in previous days with more (about 80 ppbv) ozone, but weaker backscatter. Ozone in the lowest 500 m and at the surface peaked at about 60 ppbv* around 1300 PDT when the lidar showed the elevated layer to still be distinct from the CBL. The concentrations then declined slightly until around 1630 PDT when the low level winds shifted to the NW and the elevated layer merged with the CBL leading to a second ozone peak of about 65 ppbv at the surface. No obvious smoke from the still small (40 acre) Serpa Fire that started around 1300 PDT about 100 km to the north.