WEBVTT FILE 1 00:00:02.120 --> 00:00:07.380 Good morning and welcome to the NASA hyperwall presentation this morning. 2 00:00:07.580 --> 00:00:09.720 We are going to be talking about aerosols. 3 00:00:09.760 --> 00:00:11.520 Aerosols are one of the most important 4 00:00:11.520 --> 00:00:16.300 and as yet still uncertain elements of the climate system 5 00:00:16.600 --> 00:00:21.080 and the best estimates that we have 6 00:00:21.080 --> 00:00:24.840 of both the distribution and composition 7 00:00:24.840 --> 00:00:28.620 and the impact they have on clouds and climate 8 00:00:28.620 --> 00:00:34.840 and air quality come from a series of a set of measurements 9 00:00:34.840 --> 00:00:38.280 that are run through this project called AERONET. 10 00:00:38.280 --> 00:00:41.160 You are going to be hearing from Brent Holben 11 00:00:41.160 --> 00:00:43.820 who's the principal investigator for AERONET 12 00:00:43.820 --> 00:00:45.820 at NASA's Goddard Space Flight Center 13 00:00:46.100 --> 00:00:47.820 and so over to Brent. (Introduction by Dr. Gavin Schmidt who is NASA’s Senior Climate Advisor) 14 00:00:50.920 --> 00:00:53.100 Hello, my name is Brent Holben. 15 00:00:53.140 --> 00:00:58.100 I'm the project scientist for the AERONET project 16 00:00:58.100 --> 00:01:00.940 and I'd like to welcome you all to Mount AERONET 17 00:01:00.940 --> 00:01:08.380 here on the top of building 33 where we provide calibration for all of our instruments 18 00:01:08.380 --> 00:01:14.740 that are in the network. AERONET is a relatively small program 19 00:01:14.740 --> 00:01:19.140 that is designed to measure aerosol concentrations 20 00:01:19.140 --> 00:01:24.860 and properties from a ground-based network of sun photometers, 21 00:01:24.860 --> 00:01:25.800 these guys here, 22 00:01:25.900 --> 00:01:31.060 for primarily for validation of satellite retrievals of aerosols. 23 00:01:31.060 --> 00:01:34.260 We know the energy at the top of the atmosphere. 24 00:01:34.260 --> 00:01:37.980 We're measuring it at the bottom of the atmosphere with these guys. 25 00:01:37.980 --> 00:01:40.980 We can actually point it at the sun. 26 00:01:40.980 --> 00:01:42.980 It has a filter wheel here that, uh, 27 00:01:42.980 --> 00:01:45.880 looks at nine spectral channels and 28 00:01:45.880 --> 00:01:51.280 we use that difference between the top and the bottom of the atmosphere 29 00:01:51.280 --> 00:01:54.980 to characterize the properties, 30 00:01:54.980 --> 00:01:59.300 as well as to measure the concentration of those aerosols. 31 00:01:59.300 --> 00:02:03.740 Also, there is a very large land surface community 32 00:02:03.740 --> 00:02:06.080 that doesn't care anything about aerosols, 33 00:02:06.080 --> 00:02:07.840 but they want to see what's going on with the 34 00:02:07.840 --> 00:02:10.180 vegetation and surface characteristics. 35 00:02:10.380 --> 00:02:13.060 So, they need to remove the atmosphere. 36 00:02:13.140 --> 00:02:17.840 So, the data from this basically provides 37 00:02:17.840 --> 00:02:21.140 that information to correct the satellite imagery 38 00:02:21.140 --> 00:02:25.360 so you can get a better view of the surface characterization. 39 00:02:25.360 --> 00:02:30.180 There's also the ocean community which is interested in ocean color 40 00:02:30.180 --> 00:02:34.940 and the concentration of chlorophyll and particulates in the water. 41 00:02:34.940 --> 00:02:38.980 And aerosols contributed approximately 90% of the signals, 42 00:02:38.980 --> 00:02:43.160 so it's very important to very accurately remove t 43 00:02:43.160 --> 00:02:49.560 he aerosol signal from that satellite ocean color signal. 44 00:02:49.560 --> 00:02:54.200 All together, there are about 450 sites worldwide and 45 00:02:54.200 --> 00:02:56.140 they're very well distributed. 46 00:02:56.140 --> 00:02:59.120 In all kinds of ecosystems 47 00:02:59.120 --> 00:03:02.860 and all kinds of aerosol environments. 48 00:03:02.860 --> 00:03:06.380 And as satellites come and go, 49 00:03:06.380 --> 00:03:12.080 this project is simple enough and robust enough 50 00:03:12.080 --> 00:03:16.640 that it keeps producing more and more information 51 00:03:16.640 --> 00:03:22.540 at a higher and higher data rate, at a higher and higher distribution. 52 00:03:22.540 --> 00:03:27.840 So, I suspect that in the long term, we're going to grow 53 00:03:27.840 --> 00:03:32.360 to several thousand instruments. And because 54 00:03:32.360 --> 00:03:34.960 it's a relatively inexpensive program, 55 00:03:34.960 --> 00:03:41.560 I think that the future bodes very well for providing more data 56 00:03:41.560 --> 00:03:45.620 for not just NASA, but the entire globe. 57 00:03:50.160 --> 00:03:53.120 Okay I'm down for Mt. AERONET now. 58 00:03:55.020 --> 00:03:55.900 I'd like to make a point before we move forward. 59 00:03:56.460 --> 00:03:58.620 Consider AERONET measurements this way, 60 00:03:59.180 --> 00:04:01.300 humans tend to look horizontally. 61 00:04:01.300 --> 00:04:03.300 We appreciate visibility, 62 00:04:03.300 --> 00:04:05.300 and we have a notion of what haze is, 63 00:04:05.300 --> 00:04:08.820 but it's really transmissivity of the atmosphere. 64 00:04:08.820 --> 00:04:10.820 AERONET looks up through the atmosphere 65 00:04:14.480 --> 00:04:16.000 to measure a similar transmissivity parameter. 66 00:04:16.300 --> 00:04:17.340 AERONET has been growing and 67 00:04:19.220 --> 00:04:20.920 improving for 28 years, and in 2021, 68 00:04:21.000 --> 00:04:24.240 this year approximately 500 ground stations 69 00:04:24.240 --> 00:04:26.240 have contributed to our database. 70 00:04:26.240 --> 00:04:29.020 It's effectively an aerosol climatology. 71 00:04:29.020 --> 00:04:32.880 The map in the upper left shows 72 00:04:32.880 --> 00:04:34.880 the contributing sites this year. 73 00:04:35.520 --> 00:04:37.620 This is a Federated network with 74 00:04:37.620 --> 00:04:40.540 partner collaborations in all continents, 75 00:04:40.540 --> 00:04:42.540 97 countries and territories. 76 00:04:42.540 --> 00:04:45.420 The network functions because 77 00:04:45.420 --> 00:04:48.680 scientists and technicians working in Partnership 78 00:04:50.600 --> 00:04:52.340 share their data in a public domain database 79 00:04:52.340 --> 00:04:53.260 for the community. 80 00:04:53.740 --> 00:04:56.560 It takes Global Village to make this work. 81 00:04:56.560 --> 00:04:56.640 Okay, but still, why does NASA It takes Global Village to make this work. 82 00:04:56.640 --> 00:05:00.520 Okay, but still, why does NASA 83 00:05:00.520 --> 00:05:02.520 or anybody need AERONET? 84 00:05:02.520 --> 00:05:04.520 Why ask AERONET? 85 00:05:04.520 --> 00:05:07.320 Let's go to the satellite and models. 86 00:05:09.760 --> 00:05:12.420 My favorite animation, GMAO. 87 00:05:12.540 --> 00:05:14.420 They do everything. 88 00:05:14.420 --> 00:05:16.860 They ingest the satellite data, 89 00:05:16.860 --> 00:05:18.860 in this case MODIS, 90 00:05:18.860 --> 00:05:21.780 combine it with meteorology sources, 91 00:05:21.780 --> 00:05:24.260 microphysics of the aerosols. 92 00:05:24.260 --> 00:05:27.040 Then it transports and modifies aerosols 93 00:05:27.080 --> 00:05:30.320 around the planet as a very realistic representation 94 00:05:30.340 --> 00:05:32.320 of the aerosol environment. 95 00:05:32.320 --> 00:05:34.700 Note, dust blowing off West Africa 96 00:05:34.700 --> 00:05:36.700 and transported across the Atlantic. 97 00:05:36.700 --> 00:05:40.400 Smoke from wildfires in the US and Canada. 98 00:05:40.400 --> 00:05:44.820 Sea salt, all modified by meteorology and physics 99 00:05:44.820 --> 00:05:46.820 embedded in the code and nudged by 100 00:05:46.820 --> 00:05:48.820 new data from the satellites. 101 00:05:48.820 --> 00:05:52.260 We will see an additional clip showing transport later. 102 00:05:52.660 --> 00:05:57.080 The question is how accurate are the data 103 00:05:57.080 --> 00:05:59.620 from the satellites and model simulations? 104 00:05:59.620 --> 00:06:02.540 We need error bars put on the retrievals, 105 00:06:02.540 --> 00:06:04.460 so how do we do that? 106 00:06:04.460 --> 00:06:04.540 Let's go to the next slide. so how do we do that? 107 00:06:04.540 --> 00:06:07.560 Let's go to the next slide. 108 00:06:07.560 --> 00:06:10.860 We need to go to where the aerosols are. 109 00:06:10.860 --> 00:06:12.860 We need to kind of get dirty. 110 00:06:12.860 --> 00:06:16.760 The upper left-hand Corner shows an 111 00:06:16.760 --> 00:06:18.760 active fire in the Forest Clearing. 112 00:06:18.760 --> 00:06:20.760 It’s man made. 113 00:06:21.100 --> 00:06:25.180 Notice the dark smoke plume generating a cumulous cloud. 114 00:06:25.920 --> 00:06:32.400 Clearly a chaotic and a massive aerosol cloud interaction. 115 00:06:32.400 --> 00:06:34.400 It is very difficult to measure. 116 00:06:34.400 --> 00:06:37.340 The very hot fire the panel below, 117 00:06:37.340 --> 00:06:39.340 well I don't want to get in that, 118 00:06:39.340 --> 00:06:42.280 but some people do, to get the ground truth data. 119 00:06:42.540 --> 00:06:47.240 We send planes in on challenging sampling missions 120 00:06:47.240 --> 00:06:51.580 to measure and ultimately understand the processes for the models. 121 00:06:51.580 --> 00:06:56.900 How about the picture of the container ship idling in a harbor on a hazy afternoon – 122 00:06:56.900 --> 00:06:59.640 fossil-fuel aerosols. 123 00:06:59.640 --> 00:07:04.660 Then, there's the dust storm about to overtake suburbia. 124 00:07:05.640 --> 00:07:11.080 The melon vendor is sampling dust with his eyes and his nose and skin, 125 00:07:11.080 --> 00:07:14.820 not exactly scientific, but he knows what it is. 126 00:07:14.820 --> 00:07:19.420 It works for him. AERONET takes easy street. 127 00:07:19.420 --> 00:07:23.840 Robots sit and wait for aerosols to come to them. 128 00:07:23.840 --> 00:07:25.320 Measurements every five minutes. 129 00:07:25.320 --> 00:07:28.960 No weekends off. No holidays allowed - 24/7. 130 00:07:29.420 --> 00:07:32.740 Let’s go on a global tour of AERONET. 131 00:07:34.660 --> 00:07:36.440 Here we are in Europe. 132 00:07:36.440 --> 00:07:38.880 It is not just NASA doing AERONET. 133 00:07:38.880 --> 00:07:41.840 Our calibration partners in Lille and Valladolid 134 00:07:41.840 --> 00:07:43.840 maintain the European Network 135 00:07:44.800 --> 00:07:47.800 and the result has been a great gift to the aerosol community. 136 00:07:48.060 --> 00:07:52.760 Check out the map - the density of observations often shows connectivity 137 00:07:52.900 --> 00:07:57.080 between the adjacent instruments. The validation scientists, 138 00:07:57.160 --> 00:08:03.540 we have statistics. The breadth of the science sites from Iceland to Poland, 139 00:08:03.540 --> 00:08:06.540 Scandinavia to the Iberian Peninsula, 140 00:08:06.620 --> 00:08:11.340 Turkey to Glasgow. UKMET has one here. 141 00:08:11.340 --> 00:08:16.780 Rural, urban, over water, mountains - 142 00:08:16.780 --> 00:08:22.280 that diversity and density of the Relentless routine observations 143 00:08:22.280 --> 00:08:24.280 make AERONET Europe exceptional! 144 00:08:24.280 --> 00:08:26.280 You have aerosol transport. 145 00:08:26.800 --> 00:08:28.940 Check out the GMAO simulation! 146 00:08:28.940 --> 00:08:31.280 We must credit the scientists, 147 00:08:31.280 --> 00:08:34.240 the governmental and University institutions 148 00:08:34.240 --> 00:08:37.440 that have recognized the importance of these measurements. 149 00:08:37.440 --> 00:08:40.920 Okay, let’s do something a little different. 150 00:08:40.920 --> 00:08:44.980 Let's transport ourselves to Southeast Asia and warm up. 151 00:08:44.980 --> 00:08:50.280 Southeast Asia - another GMAO simulation – 152 00:08:50.280 --> 00:08:52.000 zoomed into southeast Asia. 153 00:08:52.000 --> 00:08:55.560 Note that indonesian fires light up in September 154 00:08:55.560 --> 00:09:00.640 on the satellite image shows thousands of hotspots likely ag fires 155 00:09:00.640 --> 00:09:04.300 in Thailand, Laos, and Myanmar in March and April. 156 00:09:04.940 --> 00:09:10.480 Aerosols don't respect country boundary, country regulations, 157 00:09:10.680 --> 00:09:13.620 and are transported to the East! 158 00:09:13.620 --> 00:09:18.320 Seven Seas is a long-running bootstrap international program 159 00:09:18.320 --> 00:09:23.380 established by host country scientists in 7 Southeast Asian countries. 160 00:09:23.380 --> 00:09:28.480 The mission - characterize aerosol meteorological interactions across 161 00:09:28.480 --> 00:09:34.140 southeast Asia and establish a multinational collaborative 162 00:09:34.140 --> 00:09:38.960 database of regional ground-based observations. 163 00:09:38.960 --> 00:09:41.240 Provide space space retrieval algorithms 164 00:09:41.240 --> 00:09:43.740 and modeling datasets and 165 00:09:44.540 --> 00:09:47.700 AERONET is the validation anchor in all of this. 166 00:09:49.540 --> 00:09:57.760 Collaboration continues. The network continues to expand adding to our regional aerosol climatology. 167 00:09:59.560 --> 00:10:10.780 Ladies and gentlemen, I give you topography. Beautiful Japanese Alps - spectacular, but topography messes up our simple view of the Earth. 168 00:10:10.780 --> 00:10:24.320 It is difficult to do remote sensing of any type in steep Mountainous settings. Inversions trap Aerosols upslope, and downslope winds make a mockery of our global models. 169 00:11:45.160 --> 00:11:49.480 The Amazon - everybody knows what's going on in the Amazon. 170 00:11:49.480 --> 00:11:51.480 And everybody is an expert. 171 00:11:51.960 --> 00:11:55.380 Forest conversion, land cover change. 172 00:11:55.380 --> 00:11:57.380 Look at the animation – 173 00:11:57.440 --> 00:12:01.600 burning monoculture in a river of smoke pours south. 174 00:12:01.600 --> 00:12:06.440 The issues are climate affects, ecosystem function, 175 00:12:06.440 --> 00:12:09.880 and health effects on 20 million people that live in the Amazon. 176 00:12:10.780 --> 00:12:14.960 AERONET has been measuring in the Amazon since 1992. 177 00:12:14.960 --> 00:12:19.180 First with Brazilian space agency (aeb), 178 00:12:19.180 --> 00:12:21.520 and later with University of San Paulo, 179 00:12:21.520 --> 00:12:24.280 and other agencies and university scientists. 180 00:12:25.060 --> 00:12:27.740 Aerosol climatology is emerging and 181 00:12:27.740 --> 00:12:30.820 note the annual 3 month pulse. 182 00:12:30.820 --> 00:12:34.320 Year-by-year AERONET sites in 183 00:12:34.320 --> 00:12:38.340 Brazil, Bolivia, Paraguay, Argentina, and Uruguay 184 00:12:38.340 --> 00:12:42.140 capture those pulses as they exit over the South Atlantic. 185 00:12:42.140 --> 00:12:45.360 AERONET further compliments detailed 186 00:12:45.400 --> 00:12:47.700 meteorological in situ measurements at the 187 00:12:47.700 --> 00:12:51.340 300 m ATTO tower near Manaus 188 00:12:51.340 --> 00:12:54.820 to chronicle the effects of a changing atmosphere 189 00:12:54.920 --> 00:12:57.420 on a pristine part of the Amazon basin. 190 00:12:59.420 --> 00:13:00.300 Next slide please. 191 00:13:00.300 --> 00:13:05.160 Africa looms large in every facet of the earth's climate system, 192 00:13:05.200 --> 00:13:10.500 and for aerosols it is easily depicted in the GMAO animation. 193 00:13:10.600 --> 00:13:13.900 We know that vast quantities of mineral dust are transported 194 00:13:13.900 --> 00:13:16.980 over the Atlantic, Mediterranean, Caribbean, 195 00:13:17.000 --> 00:13:21.680 South America, and Europe. AERONET is there to spot check 196 00:13:21.680 --> 00:13:23.680 the satellites and models. 197 00:13:23.680 --> 00:13:26.120 We are there in the Sahara, and Sahel, 198 00:13:26.120 --> 00:13:28.320 including islands surrounding the continent. 199 00:13:28.320 --> 00:13:32.060 Likewise, the largest area of biomass burning 200 00:13:32.060 --> 00:13:36.820 on the planet occur every year in a north to south migration 201 00:13:36.820 --> 00:13:39.100 of anthropogenic biomass burning. 202 00:13:39.100 --> 00:13:41.460 Check out the animation on the upper right. 203 00:13:41.920 --> 00:13:46.060 AERONET began observations in Zambia in 1997 204 00:13:46.060 --> 00:13:51.380 and greatly expanded observations during the 1990s during 205 00:13:51.380 --> 00:13:55.380 NASA and University of the Witwatersrand (Wits), Safari 2000 206 00:13:55.380 --> 00:13:59.680 airborne campaign to understand the processes and magnitude 207 00:13:59.680 --> 00:14:05.020 of the burning. That ushered in the Eos era of validation 208 00:14:05.020 --> 00:14:10.800 for the Terra satellite. Antonio Queface a young graduate student at Wits 209 00:14:10.800 --> 00:14:14.480 volunteered to man an AERONET site in southern Mozambique, 210 00:14:14.480 --> 00:14:17.220 his home country for the campaign. 211 00:14:17.220 --> 00:14:21.700 Today, he is a professor of physics at University 212 00:14:21.700 --> 00:14:24.160 and is leading his students in measurements and 213 00:14:24.160 --> 00:14:26.160 assessments of AERONET data. 214 00:14:26.160 --> 00:14:28.300 Last slide please. 215 00:14:29.620 --> 00:14:31.820 There are five hundred stories, and 216 00:14:31.820 --> 00:14:34.080 stories within stories to be told. 217 00:14:34.080 --> 00:14:36.080 I’ve nearly run out of time. 218 00:14:36.080 --> 00:14:39.520 I'd like to show you two historic science results 219 00:14:39.520 --> 00:14:40.620 from AERONET. 220 00:14:40.740 --> 00:14:43.540 The upper left-hand panel is a figure showing 221 00:14:43.540 --> 00:14:47.040 the first published MODIS/Terra versus AERONET 222 00:14:47.040 --> 00:14:49.880 comparisons over land and water. 223 00:14:50.240 --> 00:14:54.940 Validation with Statistics, and it was good! 224 00:14:54.940 --> 00:14:57.940 This analysis is now routine. 225 00:14:57.940 --> 00:15:03.060 The upper right is a published figure showing the AERONET climate parameter. 226 00:15:03.060 --> 00:15:07.300 Single scattering albedo for 3 aerosol types. 227 00:15:07.300 --> 00:15:10.960 All values above the blue line which we superimposed 228 00:15:10.960 --> 00:15:15.500 on the figure would contribute to cooling the atmosphere 229 00:15:15.500 --> 00:15:20.040 and those below the red line would likely warm the atmosphere. 230 00:15:20.040 --> 00:15:26.140 In conclusion, we have aerosol climatology, validation and 231 00:15:26.140 --> 00:15:29.340 research owing to the hard work and dedication of the 232 00:15:29.340 --> 00:15:31.540 science community working together. 233 00:15:31.540 --> 00:15:36.240 On behalf of the research and technical staff at Goddard, 234 00:15:36.240 --> 00:15:40.880 Lille, Valladolid, Boulder, and Beijing, 235 00:15:40.880 --> 00:15:45.040 and the calibration sites at Mauna Loa and Izaña, 236 00:15:45.040 --> 00:15:49.880 and the hundreds of scientists and technicians at 500 sites 237 00:15:49.880 --> 00:15:51.880 in 97 countries and territories, 238 00:15:52.400 --> 00:15:55.480 we wish COP26 every success. 239 00:15:55.480 --> 00:15:59.580 Remember, if you're not sure ask AERONET. 240 00:15:59.840 --> 00:16:01.500 thank you