WEBVTT FILE 1 00:00:00.000 --> 00:00:00.230 2 00:00:00.250 --> 00:00:04.380 The system is called Soluble Acidic Gases and Aerosols. 3 00:00:04.400 --> 00:00:05.330 We have two parts to it. 4 00:00:05.350 --> 00:00:08.090 One is a filter that's a bulk filter. 5 00:00:08.110 --> 00:00:10.510 It collects aerosols from very tiny sizes 6 00:00:10.530 --> 00:00:12.450 up to about 5 microns. 7 00:00:12.470 --> 00:00:14.670 So we measure 8 or 9 ions, 8 00:00:14.690 --> 00:00:16.040 tracers of pollution, 9 00:00:16.060 --> 00:00:19.160 sea salt, biomass burning, and dust. 10 00:00:19.180 --> 00:00:21.300 So the combinations or the ratios 11 00:00:21.320 --> 00:00:23.160 tells us something about the source of the air. 12 00:00:23.180 --> 00:00:23.560 13 00:00:23.580 --> 00:00:26.430 Then we run the mist chamber IC sampler, 14 00:00:26.450 --> 00:00:28.400 which collects soluble gases 15 00:00:28.420 --> 00:00:31.440 and fine, submicron aerosols into a liquid. 16 00:00:31.460 --> 00:00:32.430 And we make injections 17 00:00:32.450 --> 00:00:35.230 right onto the IC on the airplane 18 00:00:35.250 --> 00:00:36.780 so we get data about 3 or 4 minutes 19 00:00:36.800 --> 00:00:39.060 after we collect the sample. 20 00:00:39.080 --> 00:00:40.630 And there the focus is 21 00:00:40.650 --> 00:00:42.980 primarily on nitrate and sulfate. 22 00:00:43.000 --> 00:00:44.790 Well the filter sampling, 23 00:00:44.810 --> 00:00:46.290 it's a manual system. 24 00:00:46.310 --> 00:00:48.220 So you got to put the filters in there 25 00:00:48.240 --> 00:00:50.110 and open the valves. 26 00:00:50.130 --> 00:00:53.160 So every few minutes I gotta get up 27 00:00:53.180 --> 00:00:54.880 and put in another filter, 28 00:00:54.900 --> 00:00:56.130 and take the ones out 29 00:00:56.150 --> 00:00:58.200 and put them back here in the cooler 30 00:00:58.220 --> 00:01:01.020 so they don't degrade. 31 00:01:01.040 --> 00:01:02.600 I think that we're going to see 32 00:01:02.620 --> 00:01:03.430 really clean air, 33 00:01:03.450 --> 00:01:04.500 but we're also going to see 34 00:01:04.520 --> 00:01:07.880 pockets of pollution from various sources. 35 00:01:07.900 --> 00:01:09.000 A long time ago 36 00:01:09.020 --> 00:01:10.850 we came down to the Southern Ocean 37 00:01:10.870 --> 00:01:14.390 on a NASA mission called ChemTropics, 38 00:01:14.410 --> 00:01:15.320 and the same idea 39 00:01:15.340 --> 00:01:16.780 we're trying to get into the tropics 40 00:01:16.800 --> 00:01:18.730 and find this really clean air. 41 00:01:18.750 --> 00:01:20.620 But we were seeing biomass burning plumes 42 00:01:20.640 --> 00:01:22.690 from Africa and South America 43 00:01:22.710 --> 00:01:24.650 in the middle of the Pacific Ocean. 44 00:01:24.670 --> 00:01:27.020 So I think we will see stuff like that. 45 00:01:27.040 --> 00:01:29.500 It's just not clear 46 00:01:29.520 --> 00:01:31.430 how much of an effect does that have. 47 00:01:31.450 --> 00:01:33.590 If you don't go after them 48 00:01:33.610 --> 00:01:34.650 and you just fly around, 49 00:01:34.670 --> 00:01:36.610 do you see them 10 percent of the time 50 00:01:36.630 --> 00:01:38.180 or 50, or...? We don't know. 51 00:01:38.200 --> 00:01:42.200 So that's why this mission is not targeting them. 52 00:01:42.220 --> 00:01:43.140 It's trying to sample them 53 00:01:43.160 --> 00:01:44.130 as they happen to be there. 54 00:01:44.150 --> 00:01:45.880 We're certainly going to hit them 55 00:01:45.900 --> 00:01:48.380 throughout the four seasons 56 00:01:48.400 --> 00:01:51.425 and in all different parts of the trip.