2250 Takeoff, climb to ~20,000' southbound
2319:35-0154:00 20,000' leg
0201:18-0211:30 10,000' lidar leg across circle, start 53.41S 137.52E
0211:30 Circular descent @1000 fpm to 100'
BL top about 3000', with well-mixed layer about 1600' asl
0222:08-0252:08 30 min CCW circular pattern at 100'
90/270 climb to 500'
0255:05-0325:05 30 min CW circular pattern at 500'
90/270 climb to 1000'
0327:55-0357:55 30 min CCW circular pattern at 1000'
90/270 climb to 1500'
0401:10-0431:10 30 min CW circular pattern at 1500'
Descent to 100'
0437:00-0449:00 100' diameter crossing
Climb to inversion
0451:42-0503:15 Porpoise across diameter at inversion, 2200-4000'
Dryout layer was above porpoises, at 5000'
0504:00 90/270 rapid climb to do lidar leg enroute to Hobart
(thus, not directly across circle)
0520:30-0704:18 20,000' leg toward Hobart
0704:18 Begin descent into Hobart
0732 Land at Hobart
We went farther south than the original plan to find clear air. It looked best at the southern end of the partially-cloudy area we initially targeted. As we descended it became clear that there was more than one layer beneath the inversion. We chose to study the well-mixed layer, which appeared to be about 1600' deep. The ambient temperature at 100' was 2.7 C, while the dew point was around -1 C, varying a bit around the circle. The southeastern portion of the circle passed under some stratoQ, which seemed to thicken with later circles. The NW portion of the circle was in air that had more open area than broken clouds.
At 0625 (and occasionally on the ferry down as well) McMurry saw high ultrafine CN, but H2SO4 vapor was not elevated simultaneously. There was one possible exhaust encounter during the circles, at about 0401-0402. Scott saw elevated NO, whereas during the first circles it was <5 ppt and up to 10 ppt at 0420 on a later circle. On both ferry legs, down and back, the cloud structures were very interesting. At times the lidar clearly showed two cloud layers, while at other times the upper layer prevented any conclusions about the layers below. With both the lidar and RSTB we were able to see cellular structures in some areas.
Most of the instrumentation operated normally. Clarke lost his 3025 UCN counter, however, and the switching valve tht selected or deselected the impactor at the nephelometer input stuck in such a way that it may not be possible to know which data did or did not have the impactor in place. The lidar operated without the IR wavelength. The external sampler capping valve did not appear to be seating well. Ammonia measurements were made, although it is not yet clear when defendable data will be produced.