WEBVTT FILE 1 00:00:05.205 --> 00:00:09.275 Clouds are one of the most important aspects of climate and we need to 2 00:00:09.275 --> 00:00:15.081 understand how clouds work better. Y’know, we have instrumentation that 3 00:00:15.081 --> 00:00:20.653 can measure physical properties of clouds, but actually being able to collect samples 4 00:00:20.653 --> 00:00:26.760 of the cloud water we’re flying through to analyze the chemistry of those cloud 5 00:00:26.760 --> 00:00:31.431 droplets is an important part of the puzzle that we haven't yet been able 6 00:00:31.431 --> 00:00:33.333 to do in this mission. 7 00:00:35.802 --> 00:00:40.707 People have collected cloud water. I mean, clearly when the aircraft flies through 8 00:00:40.707 --> 00:00:47.614 clouds the airframe collects water. Unfortunately, that fine detail that 9 00:00:47.614 --> 00:00:51.751 were trying to tease out from the cloud chemistry is lost when you contaminated 10 00:00:51.751 --> 00:00:55.655 with everything that the aircraft has been picking up through it’s flight. 11 00:00:55.655 --> 00:01:01.494 So the idea here is essentially it's a control. We have a way of controlling 12 00:01:01.494 --> 00:01:07.167 what we take in as cloud water and we try to reject the stuff they don't want 13 00:01:07.167 --> 00:01:08.134 to include. 14 00:01:09.636 --> 00:01:14.641 The clouds we are measuring here are what is known as boundary layer clouds. 15 00:01:14.641 --> 00:01:19.212 And that's really what's important for the NAAMES mission, is understanding 16 00:01:19.212 --> 00:01:21.514 those low boundary layer clouds over the water. 17 00:01:23.583 --> 00:01:28.788 So, these clouds have, essentially, a fairly well defined profile of liquid 18 00:01:28.788 --> 00:01:29.756 water. 19 00:01:30.723 --> 00:01:35.662 As you go higher, the cloud gets generally thicker so there is more cloud water 20 00:01:35.662 --> 00:01:36.629 available. 21 00:01:36.629 --> 00:01:42.335 Down at the bottom of the cloud the cloud droplets aren't as large and there's not 22 00:01:42.335 --> 00:01:44.637 as much clout water available for collection. 23 00:01:44.637 --> 00:01:49.742 We want to target both of those regions, both the cloud base and the cloud top, 24 00:01:49.742 --> 00:01:55.515 because even though the cloud base is harder to get a large volume of cloud 25 00:01:55.515 --> 00:02:03.223 water collected, it has interesting information about the aerosols that 26 00:02:03.223 --> 00:02:05.425 were involved in activating those cloud water droplets. 27 00:02:05.425 --> 00:02:11.498 The top of the cloud, it's juicier there's more liquid water content 28 00:02:11.498 --> 00:02:15.468 availablefor us to collect, but essentially it's potentially more dilute. 29 00:02:15.468 --> 00:02:23.042 The interesting thing is we know how the water mass changed vertically, but 30 00:02:23.042 --> 00:02:28.348 if the concentrations show something different that's essentially information 31 00:02:28.348 --> 00:02:32.051 about chemistry that's happening within the cloud, which is one of the areas of 32 00:02:32.051 --> 00:02:35.021 study that I'm really interested in trying to understand better. 33 00:02:37.323 --> 00:02:43.796 What were trying to understand is the small amount of impurities that are 34 00:02:43.796 --> 00:02:44.764 in the cloud. 35 00:02:44.764 --> 00:02:54.107 They may have come from locally produced, uh, in-situ production of these species 36 00:02:54.107 --> 00:02:59.045 in the cloud water through this wet chemistry, if you like in the cloud. 37 00:02:59.045 --> 00:03:04.350 Or it could have been dry chemistry below the cloud, so it didn’t need 38 00:03:04.350 --> 00:03:07.253 the cloud to perform that chemical reaction. 39 00:03:07.253 --> 00:03:09.222 We’re measuring below the cloud. 40 00:03:09.222 --> 00:03:13.226 We know what the composition of aerosol and gases are below the cloud. 41 00:03:13.226 --> 00:03:17.630 With this cloud water we add another piece of the puzzle. 42 00:03:17.630 --> 00:03:22.368 We try to understand other things like sulfate chemistry which is an important 43 00:03:22.368 --> 00:03:24.137 aspect of this study. 44 00:03:26.839 --> 00:03:34.247 The ideas that within clouds you have gasses, you have aerosols, and you have 45 00:03:34.247 --> 00:03:37.317 activated aerosol particles which are the cloud droplets. 46 00:03:37.317 --> 00:03:43.423 The chemistry becomes that much more difficult when you have this phase change. 47 00:03:43.423 --> 00:03:50.330 You have liquid water in abundance and it acts as this new medium where chemical 48 00:03:50.330 --> 00:03:53.933 reactions can take place. When you’re out of the cloud you don’t have that. 49 00:03:56.502 --> 00:03:59.739 That's an experiment we’ll do off-line. 50 00:03:59.739 --> 00:04:02.775 So now that we've collected this cloud water—it’s going to be done with Luke 51 00:04:02.775 --> 00:04:09.182 we’ll set up an experiment and the lab and, again, it's a new technique 52 00:04:09.182 --> 00:04:13.820 and I don't believe that anybody has looked at biological particles in cloud 53 00:04:13.820 --> 00:04:18.324 water in this way, certainly in connection with a mission such 54 00:04:18.324 --> 00:04:24.731 as NAAMES, where there is a strong focus on ocean and aerosols interactions and 55 00:04:24.731 --> 00:04:29.302 how that interacts with clouds, so this is a new thing. 56 00:04:32.572 --> 00:04:36.776 We've had requests to use the cloud water we collect during this mission 57 00:04:36.776 --> 00:04:39.412 to supplement other investigators work. 58 00:04:39.412 --> 00:04:47.453 People who are outside of my knowledge in biology have taken an interest in the 59 00:04:47.453 --> 00:04:51.824 cloud water to do their analysis, particularly the kind of analysis 60 00:04:51.824 --> 00:04:57.196 that's done on seawater and use that as a comparison to see whether stuff comes 61 00:04:57.196 --> 00:05:01.134 off the ocean and makes it into clouds and how it affects the clouds. 62 00:05:01.134 --> 00:05:05.171 It's a tracer, essentially. The nice thing about using those biological 63 00:05:05.171 --> 00:05:10.943 particles is that they are a tracer that doesn't necessarily change in the same 64 00:05:10.943 --> 00:05:12.745 way that chemical tracers change. 65 00:05:12.745 --> 00:05:16.983 Chemical tracers can evolve and react into other species, 66 00:05:16.983 --> 00:05:23.556 but these biological tracers are somewhat inert in that sense to 67 00:05:23.556 --> 00:05:25.558 chemical transformations. 68 00:05:25.558 --> 00:05:32.365 That's another exciting technique that we may do to try and understand the 69 00:05:32.365 --> 00:05:38.705 connection between the clouds locally and potentially regionally transported 70 00:05:38.705 --> 00:05:41.541 particles that affect clouds. 71 00:05:43.810 --> 00:05:48.981 This probe that hangs down here is called the AC3, the axial cyclone 72 00:05:48.981 --> 00:05:50.316 cloud water collector. 73 00:05:50.316 --> 00:05:56.823 This is the new prototype collector for collecting in situ cloud water. 74 00:06:03.262 --> 00:06:07.600 In the inside of the probe, the stator which basically generates that swirl, 75 00:06:07.600 --> 00:06:09.502 it is made out of stainless steel. 76 00:06:09.502 --> 00:06:11.237 The rest of the probe is aluminum. 77 00:06:11.237 --> 00:06:16.442 To make that part out of aluminum using conventional milling would have been very 78 00:06:16.442 --> 00:06:19.379 very difficult, and taken a long time and been very costly. 79 00:06:19.379 --> 00:06:25.785 We used an experimental technique. It's steel powder that we start off with. 80 00:06:25.785 --> 00:06:28.454 It’s a process called laser sintering. 81 00:06:28.454 --> 00:06:33.960 Essentially the laser melts the steel powder and builds the shape 82 00:06:33.960 --> 00:06:37.263 in the same way that a printer would accept that it's three-dimensional. 83 00:06:37.263 --> 00:06:40.733 it's 3-D printing but for steel.