The scientific objective during this ferry leg from Brisbane to Nadi was to investigate different layers in the free troposphere by profiles and straight-and-level runs at different layers. The layers were identified by profiles, and were characterized by anomalous gas species or particle concentrations and/or water vapor content. We attempted to follow particular layers for ca. 25 min to map their spatial extent (in the direction of the transect). All of these legs were completed en route from Brisbane to Nadi to minimize the transit time of this flight.

We took off from Brisbane at 21:36 and climbed to our ferry altitude of 19,000'. At 22:11, we reached ferry altitude, and at 22:49 we were in clear air. Some scattered stratocumulus were present below us in the boundary layer. At 22:55, aerosol concentrations reported by both the 3025 (1500 p/cc) and the 3010 (1100 p/cc) were quite high. At 23:05, the broken stratocumulus layer ended and was replaced by a fairly thick assortment of cumulus clouds with tops at 7000'. This region ended at 23:12 and there appeared to be a clear region for about the next 80 miles, after which more low cumulus clouds were visible.

At 23:21 we descended to 15,000' to look for layers. The air was mostly clear, with a few scattered cumulus clouds. At 23:43, it appeared from the lidar images that these scattered cumulus clouds occurred between ca. 3000' to 5000' ({our altitude = 15,000'}+{-4km on lidar scale = 12,000'} = 3000'). At 23:57 the cumulus clouds became smaller and more scattered, typical "popcorn" cumulus.

At 00:22 we descended to 13,000'. At 00:24 the lidar images indicated higher cumulus clouds. At 00:35 we crossed New Caledonia, and at 00:37 we skimmed very near the top of a cumulus cloud. However, no UCN were reported.

At 00:42 we descended at 500'/min to 100', crossing through a thin alto stratus layer at 00:51.

At 01:04 we ascended to 3000' for a 30 min leg. At this altitude we were approximately at cloud level, very near to the base of the scattered clouds. At 01:24 we penetrated one of these clouds. During the second half of the data leg even the unclouded air had very low visibility. At 01:35 high sulfate and large particles were reported, with concentrations of about 1000 p/cc. Someone (Porter?) speculated about the possibility of emissions from a volcano in New Guinea.

At 01:40 we descended to 100' for a low level data leg. At 01:43 the air was still very hazy (at 100'). At 01:51 the thick haze (or fog?) persisted. At 01:58 the aerosol concentration reported decreased to about 500 p/cc. At 02:09 the air cleared markedly and the sky was significantly more blue. This change coincided with an apparent steep gradient in both aerosol concentration and liquid water content.

At 02:12 we began the climb to 1300' for the next leg. At 02:14 the flight level was readjusted to 1400'. At 02:17 there were large patches of yellowish particulate matter on the ocean surface, possibly attributable to some local source of pollen. At 02:29 there was a large spike in CN.

At 02:44 we climbed to 6000'. At 02:50 the mixed layer appeared to end at 4000'. However, potential temperature increased steadily up to 7000'. At 02:53 the haze thickened. At 03:01 we found a moist layer at 5800' and attempted to sample in it for 10 min. At 03:11 we climbed 500' to get above the moist layer. At 03:14 we found drier air at 7000'.

At 03:27 we climbed to find the next layer for sampling. At 03:34 we started a smapling leg at 10,000'. At 03:37 we started heading north to allow time for one more sampling leg before landing. At 03:40 we measured very high particle concentrations of ca. 1500 p/cc. There was also some indication of UCN (i.e. {3025 conc.} > {3010 conc.}). The particles were very volatile with low total mass. At 03:53 there was another spike in the CN concentration.