6 September 1995
2:15 PM
PH: Okay. Let's summarize this flight. We did a lot on this flight. First of all headed out to south to see if we could sample over the sunphotometer site at Repressa Samuel, but that didn't work out because of clouds. So we then headed north to get out of the clouds and did CAR measurements. Should be a pretty good set of CAR measurements above the smoke, with the CAR in its usual, its regular (nadir-to-zenith) sampling mode. Then we climbed up above the smoke. We actually didn't get right above the smoke, which was probably up near 15,000 ft or so, but we climbed up to 12,000 ft. Did some sampling there. And then we chose to come down and take a closer look at several clear areas beneath us in the smoke. We sampled above and below and in a couple of clear areas. Then, in the last part of the flight, we did some brief CCN measurements beneath the bases of these small cumulus and in-cloud measurements just above the base and some measurements near cloud top as well, but that was all a bit rushed. But maybe we'll get some useful data. Okay. Art, why don't you summarize?
3:41 PM
AR: Roger. I noticed there were two thin spots in the overall haze layer. It was noticed on the way up and I think Peter has indicated the first one. Down around 3,200 to 3,500 ft and then the one around 7,500 ft, which he described. We got to what appeared to be a fuzzy top of the haze layer. We didn't quite make it all, but we were probably within 2,000 ft of the top of the haze layer at our highest elevation. And the weather situation today in terms of cumulus development was we saw something very similar to our. Oops, birds overhead, 2 o'clock. Similar to what we had seen in the Pantanal, except today we had cumulus clouds as markers for what the boundary layer was doing in these deep haze layers. That is, the boundary layer was beginning to arise beginning almost at tree top level during our circles for Jason. And then as we traveled northbound the moisture seemed to be increased as well as the convection increasing with time until we got to cumulus even up to about cumulus mediocris, I'd call them, with bases at 24[[ring]] C. That's a new record for us and it's probably about as high as cloud bases get and depths of about a kilometer maybe at max. And we sampled, a number of cloud samples below in these clouds in the vicinity of the city of Madeira. Winds are at north-northeast at the site. Cloud depth was from the north-northeast at about 5-10 knots and that was confirmed by surface weather report in that area. And we've had little or no clouds above us during this particular flight.
PH: Okay. I'll just note one thing. I think we only spotted one fire today and that was a very small one in the area that we were doing our vertical profiling over the clear and dirty smoke layers. Okay. Ray?
RW: I've spent most of the time trying to get the humidigraph to work and it did work at the beginning. Well it didn't work at the beginning but then it did work. The problem is now that there isn't enough heat to dry out the particles in the preheater. So I'm going to have to do something about that. Took lots of "no-bag" samples. In the humidigraphs were we did run and got results, I got about 30% growth, which was consistent with the Alquist nephelometer compared to the humidigraph nephelometer, one running at ambient and one running at dry. So that's encouraging.
PH: Okay, Don.
DS: Okay. To summarize, we took some CCN measurements on the way out as we climbed up to about 13,000 ft. They looked similar to how they have looked on other profiles that we have done that way. As we climbed to altitude, we ran the lidar and got some traces down to the ground. As the day progressed, the lidar showed clouds forming down below us around probably 1,500-2,000 ft and pretty homogeneous smoke layer between the clouds and a clear layer between two smoke layers. After we did that, we took some CCN measurements underneath the clouds and at the present time we're getting about 75-150 particles at the 0.5% supersaturation range going up to about 300 at the high supersaturation.
AR: Peter, I remembered one thing I wanted to add. That the in-cloud visibility in these little clouds near the Madeira River seemed less than it was in some of the smoke infected fire clouds of similar size. The difference between those two clouds being the water content, you know the cloud base temperature, and I don't know if that's playing a large role in that but anyway I found it interesting that the visibility in cloud or in these clouds was less than in the smoky clouds.
PH: Okay, Ron. Are you ready?
RF: Yes. Primarily we did background old-smoke samples at three distinct layers. One near the surface at 3,500 ft, one at 7,800 ft and the third at 10,500 ft. Collected cans in all three layers and one in one of the gaps in-between for hydrocarbons and gases and two sets of filters for Vanderlei for mercury.
RF: Also, I think the DMPS wasn't acting too good at the beginning of the flight and we played with it for a while and changed some of the settings so I think by the end of the first batch of samples at the 10,500 ft level we started to get some good spectra there and then for the rest of the flight it looked pretty good.
PH: Okay. Jason.
JL: Okay. We did a CAR study over haze layer at 12,000 ft. CNC 1,000 at 800/cc. The cloud cover is generally much less than 1% and I put position on 2 and 5 or circles 3 each and then turned to the left, characterize the sky radiance 1 circle each, and ground is barely visible. It's over dense forest. I would say it's a good data set. Hopefully, I can get one more before I leave.
PH: Jack, anything not working today?
JR: Yes. Well, the obvious humidigraph, I think. Other than that, everything seems to be working all right. The preheater (on the humidigraph) I'm probably going to have to change, because it doesn't seem to be heating enough.