Monday, August 15: SCOOP
Day 7 of SCOOP observations. TOPAZ data were taken from 03:15 to 22:35 PDT.
Sunny skies. Maximum temperature of 26 C. Surface winds from the south/southwest all day at speeds between 5 and 15 m/s. Surface ozone* was low (30 - 40 ppbv) thru mid-day, then increased in the afternoon to a maximum of 75 ppbv, and decreased slightly in the evening. Very complex ozone structure aloft observed by TOPAZ. The main features were a 75-80 ppbv ozone layer of UTLS origin (sondes indicated very low humidity) between 2.5 and 4 km AGL in the morning, which descended and became thinner during the course of the day. Above that layer was a wide band of clean, low-ozone air with a high-ozone layer above 8.5 km AGL.
*Note: The collocated in situ ozone concentrations are known to be about 6% low.
Note: Data are preliminary.