1 00:00:00,160 --> 00:00:13,959 [Music] 2 00:00:21,500 --> 00:00:18,529 kennefa and good afternoon um I rec to 3 00:00:25,130 --> 00:00:21,510 talk about the early environment of the 4 00:00:30,320 --> 00:00:25,140 earth particularly focusing on the time 5 00:00:33,770 --> 00:00:30,330 period code akhiyan so first of all what 6 00:00:37,600 --> 00:00:33,780 is a Kian again is the time field from 7 00:00:41,540 --> 00:00:37,610 four billion to 2.5 billion years ago 8 00:00:45,830 --> 00:00:41,550 where when the the earth's surface is 9 00:00:49,639 --> 00:00:45,840 and totally covered by water and with no 10 00:00:54,920 --> 00:00:49,649 continent on only small volcanic islands 11 00:00:57,110 --> 00:00:54,930 and the higher heat works of this age 12 00:01:00,260 --> 00:00:57,120 and we believe that the volcanic 13 00:01:02,270 --> 00:01:00,270 activity was higher than today and so 14 00:01:05,240 --> 00:01:02,280 the hydrothermal activity is also higher 15 00:01:08,600 --> 00:01:05,250 than today's but the surface 16 00:01:10,870 --> 00:01:08,610 temperatures very controversial many 17 00:01:14,109 --> 00:01:10,880 people be with this period is hot 18 00:01:18,640 --> 00:01:14,119 horizontally but not social and 19 00:01:21,499 --> 00:01:18,650 biosphere is dominated by prokaryote and 20 00:01:24,200 --> 00:01:21,509 because the onset of oxygenic 21 00:01:27,499 --> 00:01:24,210 photosynthesis and adam of theories be 22 00:01:32,569 --> 00:01:27,509 able to have been free from molecular 23 00:01:36,649 --> 00:01:32,579 oxygen instead the geology textbook said 24 00:01:42,760 --> 00:01:36,659 you know co2 as a main component of the 25 00:01:46,249 --> 00:01:42,770 atmosphere along with maybe nitrogen but 26 00:01:49,789 --> 00:01:46,259 the current did quantitative estimate of 27 00:01:52,249 --> 00:01:49,799 the co2 levels as to a model debate how 28 00:01:55,520 --> 00:01:52,259 much co2 is there we don't know yet and 29 00:01:57,590 --> 00:01:55,530 of course the other a lot of the other 30 00:02:07,999 --> 00:01:57,600 gaseous species in the atmosphere is 31 00:02:12,350 --> 00:02:08,009 largely unknown so I'd like to focus on 32 00:02:13,690 --> 00:02:12,360 the three questions in my talk today and 33 00:02:19,509 --> 00:02:13,700 how much 34 00:02:24,130 --> 00:02:19,519 alchy unanimously and more broadly 35 00:02:26,740 --> 00:02:24,140 speaking how and on what control the 36 00:02:29,770 --> 00:02:26,750 lyrics state-of-the-art Ian Artemis's 37 00:02:34,240 --> 00:02:29,780 and chemistry atmosphere is very 38 00:02:39,880 --> 00:02:34,250 important also for climate through the 39 00:02:42,220 --> 00:02:39,890 greenhouse effect so finally I talked 40 00:02:47,850 --> 00:02:42,230 about the link between the uttermost 41 00:02:50,470 --> 00:02:47,860 chemistry and climate so I like this 42 00:02:54,430 --> 00:02:50,480 simpleton poster you know Brian man 43 00:02:59,979 --> 00:02:54,440 touching and to see the shape of 44 00:03:05,350 --> 00:02:59,989 elephant and so my talk is a I am one of 45 00:03:07,900 --> 00:03:05,360 these blind person so and to understand 46 00:03:10,780 --> 00:03:07,910 trying to understand the atmospheric 47 00:03:17,319 --> 00:03:10,790 chemistry of the pastors and my favorite 48 00:03:20,190 --> 00:03:17,329 too is stable so for isotopes this is 49 00:03:23,770 --> 00:03:20,200 very tricky because we don't know a 50 00:03:27,910 --> 00:03:23,780 direct sample of the key and atmosphere 51 00:03:32,199 --> 00:03:27,920 that's why indirectly we are trying to 52 00:03:36,970 --> 00:03:32,209 estimate or study the chemistry of the 53 00:03:41,319 --> 00:03:36,980 past atmosphere and and the surfer has 54 00:03:46,170 --> 00:03:41,329 four stables of isotopes service 32 33 55 00:03:50,800 --> 00:03:46,180 34 and 36 and the abundance of these 56 00:03:55,170 --> 00:03:50,810 isotopes for example 34 as is 4.2 1 57 00:03:57,520 --> 00:03:55,180 percent and textbook but in reality this 58 00:04:05,849 --> 00:03:57,530 abundance had changed sometimes these 59 00:04:08,229 --> 00:04:05,859 numbers not to 4.2 1 but sometimes 4.23 60 00:04:11,409 --> 00:04:08,239 or something a little bit changed 61 00:04:14,949 --> 00:04:11,419 through physical process chemical 62 00:04:17,229 --> 00:04:14,959 process or biological process and in 63 00:04:20,440 --> 00:04:17,239 that case and the indictment factor of 64 00:04:23,020 --> 00:04:20,450 surface artistry as compared to the most 65 00:04:26,620 --> 00:04:23,030 abundant sagittarius is about half of 66 00:04:29,070 --> 00:04:26,630 that of 34 s this is a golden do 67 00:04:33,000 --> 00:04:29,080 it's based in the quantum mechanics that 68 00:04:39,880 --> 00:04:33,010 we call this a must dependent relations 69 00:04:42,370 --> 00:04:39,890 but a few exception exception I of the 70 00:04:47,020 --> 00:04:42,380 photochemistry a few thousand for the 71 00:04:49,740 --> 00:04:47,030 chemistry in the gas phase reaction do 72 00:04:52,810 --> 00:04:49,750 not always this blue so that's why that 73 00:04:56,290 --> 00:04:52,820 deviation from this mass dependent 74 00:05:00,460 --> 00:04:56,300 relationship we define the deviation 75 00:05:03,760 --> 00:05:00,470 from relationship as kappa delta value 76 00:05:08,200 --> 00:05:03,770 as a non video captured over is a sign 77 00:05:12,250 --> 00:05:08,210 something help happening in the 78 00:05:14,620 --> 00:05:12,260 atmosphere atmospheric chemistry and the 79 00:05:19,440 --> 00:05:14,630 signal can be brought into the servant 80 00:05:23,980 --> 00:05:19,450 and about more than fifteen years ago 81 00:05:28,410 --> 00:05:23,990 the foie gras arrow first found the this 82 00:05:31,770 --> 00:05:28,420 sort of isotopic anomaly from the 83 00:05:37,240 --> 00:05:31,780 geologic samples particularly older than 84 00:05:39,580 --> 00:05:37,250 2.3 billion years ago so this isotopic 85 00:05:43,150 --> 00:05:39,590 anomalies produce known to be produced 86 00:05:47,470 --> 00:05:43,160 by the photodissociation reaction of so2 87 00:05:51,010 --> 00:05:47,480 very very exceptional and preserved in 88 00:05:53,470 --> 00:05:51,020 sediment is atmospheric anoxic are free 89 00:05:56,620 --> 00:05:53,480 from oxygen because the the cell for 90 00:06:00,880 --> 00:05:56,630 entering into the atmosphere as a form 91 00:06:04,510 --> 00:06:00,890 of so2 and are normally eating reaction 92 00:06:08,560 --> 00:06:04,520 is removal of this oxygen and making s 93 00:06:13,960 --> 00:06:08,570 oh this is responsible to make this 94 00:06:17,710 --> 00:06:13,970 isotope even animal but if and this is 95 00:06:20,590 --> 00:06:17,720 using form of soulful and remaining so2 96 00:06:25,750 --> 00:06:20,600 further oxidized in the sulfate they're 97 00:06:30,280 --> 00:06:25,760 very oxidizing form on sofa and the 33 98 00:06:32,860 --> 00:06:30,290 pitch compound deposited with the 99 00:06:35,200 --> 00:06:32,870 positive anomaly and the oxidizing 100 00:06:39,070 --> 00:06:35,210 species acquires negative anomaly so 101 00:06:39,480 --> 00:06:39,080 this happen under the reducing album 102 00:06:45,870 --> 00:06:39,490 fear 103 00:06:49,140 --> 00:06:45,880 but once the atmosphere is oxidizing no 104 00:06:51,809 --> 00:06:49,150 deducing species are formed that's all 105 00:06:57,510 --> 00:06:51,819 the sulfur entering into the atmosphere 106 00:07:01,559 --> 00:06:57,520 is totally oxidized into survey and it's 107 00:07:07,529 --> 00:07:01,569 positive so that's why after the lives 108 00:07:10,050 --> 00:07:07,539 of oxygen this so for isotopic anomaly 109 00:07:14,550 --> 00:07:10,060 disappeared from the sedimentary rock 110 00:07:18,270 --> 00:07:14,560 record and modeling studies show that 111 00:07:20,999 --> 00:07:18,280 the to preserve this isotopic anomaly 112 00:07:26,730 --> 00:07:21,009 the atmospheric oxygen level should be 113 00:07:29,430 --> 00:07:26,740 less than 1 ppm ok this is the basics so 114 00:07:34,409 --> 00:07:29,440 that's why the presence of this anomaly 115 00:07:38,100 --> 00:07:34,419 means the very very deducing anoxic 116 00:07:45,770 --> 00:07:38,110 conditions but we don't know yet the 117 00:07:54,320 --> 00:07:49,080 in this ten years or many people 118 00:07:58,709 --> 00:07:54,330 including our groups or study which 119 00:08:01,550 --> 00:07:58,719 process as most important for 120 00:08:05,610 --> 00:08:01,560 controlling the isotopic ratio of the 121 00:08:08,850 --> 00:08:05,620 errors of species which are deposited 122 00:08:12,860 --> 00:08:08,860 and finally preserved in the sedimentary 123 00:08:17,629 --> 00:08:12,870 rock record so in the laboratory we 124 00:08:20,580 --> 00:08:17,639 study the each step of the action and 125 00:08:27,300 --> 00:08:20,590 determine the oxygenation factors of 126 00:08:30,149 --> 00:08:27,310 four stable isotopes and so this is like 127 00:08:33,420 --> 00:08:30,159 the shape of elephant is like this is 128 00:08:37,440 --> 00:08:33,430 very complex not that this is a very 129 00:08:40,260 --> 00:08:37,450 simplified view but in reality the other 130 00:08:46,139 --> 00:08:40,270 one chemistry is very complex but in 131 00:08:49,170 --> 00:08:46,149 short that the key step is only 21 is 132 00:08:50,250 --> 00:08:49,180 the photodissociation of so2 and the 133 00:08:53,639 --> 00:08:50,260 other one is the photo excitation 134 00:08:58,410 --> 00:08:53,649 process of again sot 135 00:09:01,750 --> 00:08:58,420 so we use the experimental deep 136 00:09:05,050 --> 00:09:01,760 determined fractionation factor and put 137 00:09:09,760 --> 00:09:05,060 into the chemical reaction Network model 138 00:09:14,949 --> 00:09:09,770 and predict the isotopic are normally 139 00:09:18,310 --> 00:09:14,959 preserved in the sediment as a function 140 00:09:22,780 --> 00:09:18,320 of the chemistry of the atmosphere yeah 141 00:09:27,940 --> 00:09:22,790 and we change the surrounding chemistry 142 00:09:32,139 --> 00:09:27,950 of the atmosphere and this this pathways 143 00:09:35,199 --> 00:09:32,149 changes due to the different chemical 144 00:09:40,600 --> 00:09:35,209 composition of atmosphere and when we 145 00:09:47,110 --> 00:09:40,610 change the D co2 level and the 146 00:09:50,530 --> 00:09:47,120 calculator so this is the isotope degree 147 00:09:56,199 --> 00:09:50,540 of the isotopic anomaly and we found 148 00:10:00,670 --> 00:09:56,209 that even without no excision hyep co2 149 00:10:05,680 --> 00:10:00,680 level is not preferable to preserve the 150 00:10:09,430 --> 00:10:05,690 isotopic anomaly again even without okie 151 00:10:12,519 --> 00:10:09,440 molecular oxygen the too much co2 is 152 00:10:17,829 --> 00:10:12,529 very very oxidizing so the co2 pure co2 153 00:10:21,880 --> 00:10:17,839 atmosphere is oxidizing atmosphere so 154 00:10:26,590 --> 00:10:21,890 not only po2 river but also the PCO 155 00:10:32,670 --> 00:10:26,600 today we can constrain by this isotropic 156 00:10:38,640 --> 00:10:32,680 anomaly study so this estimate level is 157 00:10:44,890 --> 00:10:38,650 less some point Wamba this is lower than 158 00:10:48,250 --> 00:10:44,900 the the pco2 co2 level solving the faint 159 00:10:52,630 --> 00:10:48,260 young Sun Robin this figure is already 160 00:10:57,190 --> 00:10:52,640 shown by our where long rock and the 161 00:11:01,540 --> 00:10:57,200 first they should be simple and I don't 162 00:11:06,069 --> 00:11:01,550 add much thanks but this ill man shows 163 00:11:06,580 --> 00:11:06,079 the stability region liquid water on the 164 00:11:08,710 --> 00:11:06,590 surface 165 00:11:11,860 --> 00:11:08,720 yes and this one's to the increase of 166 00:11:15,040 --> 00:11:11,870 the solar luminosity so the lower bound 167 00:11:21,520 --> 00:11:15,050 means the freeze of the order and this 168 00:11:25,090 --> 00:11:21,530 is vaporized threshold so 0 less than 169 00:11:29,670 --> 00:11:25,100 0.1 but our estimate is the this is the 170 00:11:33,970 --> 00:11:29,680 maximum but the other lines of evidence 171 00:11:37,960 --> 00:11:33,980 mainly from the absence of the iron 172 00:11:42,420 --> 00:11:37,970 carbonate minerals from different ages 173 00:11:48,360 --> 00:11:42,430 of wrestling profile means much lower s 174 00:11:53,760 --> 00:11:48,370 predictive estimated more lower pco2 day 175 00:11:59,890 --> 00:11:53,770 so it's consistent with several other 176 00:12:03,790 --> 00:11:59,900 independent studies and this said that 177 00:12:06,760 --> 00:12:03,800 the the theater is not enough to keep 178 00:12:09,340 --> 00:12:06,770 the Earth's warm enough to solving the 179 00:12:16,330 --> 00:12:09,350 frame and some problem so that's why we 180 00:12:19,210 --> 00:12:16,340 need the more greenhouse gases and trace 181 00:12:24,400 --> 00:12:19,220 gases like methane or ammonium or 182 00:12:26,770 --> 00:12:24,410 somewhere else may be added not only co2 183 00:12:31,210 --> 00:12:26,780 but also the other choice greenhouse 184 00:12:34,270 --> 00:12:31,220 gases may be responsible will keep the 185 00:12:41,560 --> 00:12:34,280 Earth's warm enough to stabilize the 186 00:12:47,980 --> 00:12:41,570 water liquid water so the next thing is 187 00:12:52,240 --> 00:12:47,990 from the other isotopic anomaly and we 188 00:12:55,900 --> 00:12:52,250 can see lots more about the atmosphere 189 00:13:01,900 --> 00:12:55,910 chemistry if we look at another isotope 190 00:13:05,020 --> 00:13:01,910 economy 4036 s this is the most less 191 00:13:08,350 --> 00:13:05,030 less abundant dis abundant species among 192 00:13:12,580 --> 00:13:08,360 the four species and this x-axis shows 193 00:13:15,000 --> 00:13:12,590 the isotopic an oval 33s and y axis 194 00:13:18,220 --> 00:13:15,010 shows the isotope economy for 195 00:13:19,830 --> 00:13:18,230 self-service success and that rihanna is 196 00:13:22,130 --> 00:13:19,840 a mutually correlated 197 00:13:26,870 --> 00:13:22,140 and this red dots are all the 198 00:13:33,510 --> 00:13:26,880 sedimentary aki and geologic record and 199 00:13:35,520 --> 00:13:33,520 this the shape must be produced by the 200 00:13:37,830 --> 00:13:35,530 primary photochemical reaction because 201 00:13:43,470 --> 00:13:37,840 the normally evening the action is very 202 00:13:48,510 --> 00:13:43,480 very exceptional but if you look at 203 00:13:51,300 --> 00:13:48,520 carefully this magnitude and the slope 204 00:13:55,310 --> 00:13:51,310 or laser between the two animals I 205 00:13:59,190 --> 00:13:55,320 changed through time so that could be 206 00:14:03,240 --> 00:13:59,200 some signal from the deepest atmosphere 207 00:14:06,330 --> 00:14:03,250 but we cannot did why this magnitude and 208 00:14:11,600 --> 00:14:06,340 the slope and change through time so 209 00:14:20,460 --> 00:14:15,800 previous researchers are fertilized so2 210 00:14:24,840 --> 00:14:20,470 in the laboratory and making aissatou 211 00:14:29,010 --> 00:14:24,850 succeeded to produce the ball isotopic 212 00:14:32,580 --> 00:14:29,020 anomaly both sulphur 33 and 36 s0 is a 213 00:14:35,880 --> 00:14:32,590 no on money so the result is very 214 00:14:39,630 --> 00:14:35,890 successful to produce very very 215 00:14:44,550 --> 00:14:39,640 exceptional isotope economy but the 216 00:14:47,490 --> 00:14:44,560 problem is that no this data point it's 217 00:14:51,240 --> 00:14:47,500 consistent with the geological record so 218 00:14:54,360 --> 00:14:51,250 if this trend is produced by the mixing 219 00:14:57,780 --> 00:14:54,370 between the software derived from Adams 220 00:15:02,210 --> 00:14:57,790 fear and the other surfers in magnetic 221 00:15:05,160 --> 00:15:02,220 or biological was not derived from 222 00:15:09,260 --> 00:15:05,170 atmosphere is little always little so 223 00:15:12,480 --> 00:15:09,270 the the atmospheric component should be 224 00:15:17,730 --> 00:15:12,490 somewhere around here but no data point 225 00:15:22,520 --> 00:15:17,740 is on this right okay that's a big 226 00:15:27,260 --> 00:15:22,530 problem so why this experiment cannot 227 00:15:31,320 --> 00:15:27,270 diplo this geological you observed trend 228 00:15:33,430 --> 00:15:31,330 that we think the two key reasons one is 229 00:15:39,690 --> 00:15:33,440 the partial pressure s 230 00:15:43,330 --> 00:15:39,700 to the previous experiment is too high 231 00:15:45,610 --> 00:15:43,340 compared to the real world and another 232 00:15:49,240 --> 00:15:45,620 thing important thing is the lead of 233 00:15:52,540 --> 00:15:49,250 state and the purest so2 is very very 234 00:15:57,850 --> 00:15:52,550 oxidizing condition and authorities of 235 00:16:02,650 --> 00:15:57,860 so2 is always produce excess oxygen so 236 00:16:05,410 --> 00:16:02,660 the pure so2 and the presence of so2 237 00:16:07,900 --> 00:16:05,420 itself create a very very very oxidizing 238 00:16:10,360 --> 00:16:07,910 condition that is far different from the 239 00:16:13,480 --> 00:16:10,370 presumed reducing atmosphere of the 240 00:16:15,460 --> 00:16:13,490 arcane period so that's like to scavenge 241 00:16:20,470 --> 00:16:15,470 the excess oxygen we put the carbon 242 00:16:24,100 --> 00:16:20,480 monoxide in the chamber and do the same 243 00:16:29,890 --> 00:16:24,110 sort of experiment by using solar like 244 00:16:33,760 --> 00:16:29,900 ruv source and also we deduce the 245 00:16:36,550 --> 00:16:33,770 partial pressure so2 this is southern 246 00:16:39,840 --> 00:16:36,560 pasco 100 proscar temper scale and one 247 00:16:44,470 --> 00:16:39,850 Pasco and then we can see this trend and 248 00:16:49,330 --> 00:16:44,480 some data point are okay we can 249 00:16:52,890 --> 00:16:49,340 reproduce the geological trend this is 250 00:16:58,120 --> 00:16:52,900 because the presence of so2 itself 251 00:17:01,480 --> 00:16:58,130 change the spectrum of the UV within the 252 00:17:03,640 --> 00:17:01,490 chamber so that recall the self 253 00:17:06,059 --> 00:17:03,650 shielding effect so the different 254 00:17:10,660 --> 00:17:06,069 wavelengths region called the different 255 00:17:13,480 --> 00:17:10,670 topics fractionation so the changing the 256 00:17:18,309 --> 00:17:13,490 UV spectrum by the presence of so2 257 00:17:24,329 --> 00:17:18,319 itself is very very significant a to 258 00:17:29,440 --> 00:17:24,339 significant so this chrome shows the 259 00:17:31,990 --> 00:17:29,450 isotopic relationship 34 33 and 36 as a 260 00:17:36,810 --> 00:17:32,000 function of the total so2 column 261 00:17:40,120 --> 00:17:36,820 densities in a log scale in the previous 262 00:17:42,730 --> 00:17:40,130 experiment too high the compared to the 263 00:17:48,660 --> 00:17:42,740 modern level you know 264 00:17:54,490 --> 00:17:48,670 so even after the huge intense volcanic 265 00:17:59,380 --> 00:17:54,500 eruption like Mount Pinatubo or injector 266 00:18:04,810 --> 00:17:59,390 miyajima item is that a gigantic DD sub 267 00:18:07,240 --> 00:18:04,820 SOT is happening 1981 but still only 20 268 00:18:11,890 --> 00:18:07,250 love mounted higher than the Nova modern 269 00:18:16,390 --> 00:18:11,900 devil okay so in the actual realistic 270 00:18:21,610 --> 00:18:16,400 Ranger of the ps2 we can see the 271 00:18:25,450 --> 00:18:21,620 reasonable the injured the producers 272 00:18:28,810 --> 00:18:25,460 range of the isotope economy and in 273 00:18:32,140 --> 00:18:28,820 other words the partial pressure of so2 274 00:18:36,280 --> 00:18:32,150 can change the magnitude of the isotope 275 00:18:42,130 --> 00:18:36,290 economy so it this isotropic a memory 276 00:18:49,230 --> 00:18:42,140 can be used to monitor the pco2 PSO 20 277 00:18:55,990 --> 00:18:49,240 so or can be used to monitor the 278 00:19:00,490 --> 00:18:56,000 volcanic activity so but the problem is 279 00:19:08,040 --> 00:19:00,500 not solved yet completely because this 280 00:19:11,130 --> 00:19:08,050 slope is not like this so something 281 00:19:16,090 --> 00:19:11,140 additional fractionation is overlapped 282 00:19:21,340 --> 00:19:16,100 so we argue that this trend this yellow 283 00:19:26,160 --> 00:19:21,350 data is by using the solar like UV 284 00:19:31,270 --> 00:19:26,170 spectrum in fact we use the genome ramp 285 00:19:34,560 --> 00:19:31,280 but this is the spectrum of the genogram 286 00:19:38,799 --> 00:19:34,570 that is similar to the solar UV flux 287 00:19:43,500 --> 00:19:38,809 spectrum but if we change the spectrum 288 00:19:47,380 --> 00:19:43,510 like this and this trend is shifted so 289 00:19:50,290 --> 00:19:47,390 we can see some additional things that's 290 00:19:55,520 --> 00:19:50,300 happening the difference between the two 291 00:20:06,420 --> 00:20:03,630 the wavelength regions and so2 is not 292 00:20:10,560 --> 00:20:06,430 only followed Associated bottles of 293 00:20:17,010 --> 00:20:10,570 photoexcited and longer wavelength 294 00:20:19,710 --> 00:20:17,020 visions from about 250 nanometers so 295 00:20:23,480 --> 00:20:19,720 different process can make different 296 00:20:30,930 --> 00:20:23,490 isotopic fractionation and the solar UV 297 00:20:34,080 --> 00:20:30,940 can proceed both photo photo leases or 298 00:20:38,610 --> 00:20:34,090 photodissociation and for excitation and 299 00:20:43,770 --> 00:20:38,620 both but if we use this one only 300 00:20:47,370 --> 00:20:43,780 photoresist oh god to test to this 301 00:20:50,160 --> 00:20:47,380 scenario we cut this wavelength region 302 00:20:53,940 --> 00:20:50,170 by using the optical filter filter and 303 00:20:59,640 --> 00:20:53,950 test the photo excitation effect and yes 304 00:21:03,780 --> 00:20:59,650 we can see the huge isotopic anomalies 305 00:21:06,510 --> 00:21:03,790 and this is for different from a 306 00:21:11,180 --> 00:21:06,520 geological adoption trend but photo 307 00:21:15,690 --> 00:21:11,190 excitation process produce the this 308 00:21:20,550 --> 00:21:15,700 vector of the isotopic fractionation so 309 00:21:23,460 --> 00:21:20,560 we should think about the the mixing of 310 00:21:28,340 --> 00:21:23,470 two processes one is for dissociation 311 00:21:31,890 --> 00:21:28,350 and one is for excitation and create 312 00:21:37,730 --> 00:21:31,900 different manner of voices of extraction 313 00:21:42,840 --> 00:21:37,740 ations but the kissing is a lyric stage 314 00:21:47,160 --> 00:21:42,850 or the amount of the reducing gas in the 315 00:21:52,050 --> 00:21:47,170 atmosphere ok so2 is fertilized into a 316 00:21:55,410 --> 00:21:52,060 soul and some so2 is for excited and the 317 00:22:00,780 --> 00:21:55,420 longer wavelength regions but this 318 00:22:05,820 --> 00:22:00,790 excited states of so2 has a topic 319 00:22:07,170 --> 00:22:05,830 anomaly but easily quenched talk into 320 00:22:11,130 --> 00:22:07,180 ground state of 321 00:22:13,700 --> 00:22:11,140 so too so this isotope economy is not 322 00:22:18,150 --> 00:22:13,710 transferred into the final product 323 00:22:21,720 --> 00:22:18,160 usually but if the atmosphere containing 324 00:22:28,050 --> 00:22:21,730 reducing gas species in our experiment 325 00:22:32,060 --> 00:22:28,060 that is co but in fact the reducing 326 00:22:36,480 --> 00:22:32,070 agent remove the one oxygen from the 327 00:22:41,690 --> 00:22:36,490 exorcist of so2 and transferring s oh 328 00:22:45,180 --> 00:22:41,700 and mix together and this to signal or 329 00:22:47,520 --> 00:22:45,190 mix and transport into the final 330 00:22:54,780 --> 00:22:47,530 preserving the settlement so that's why 331 00:22:59,490 --> 00:22:54,790 the slope of these two isotopic 332 00:23:01,980 --> 00:22:59,500 anomalies can change by the amount of 333 00:23:06,750 --> 00:23:01,990 reducing gases if the autumn of stairs 334 00:23:09,900 --> 00:23:06,760 reducing and this slope is shallow but 335 00:23:12,720 --> 00:23:09,910 its atmosphere is oxidizing and this 336 00:23:15,840 --> 00:23:12,730 slope is steep and the magnitude is 337 00:23:22,680 --> 00:23:15,850 controlled by the pco2 label that it may 338 00:23:28,470 --> 00:23:22,690 be related to the volcanic activity so 339 00:23:31,020 --> 00:23:28,480 now we have a model and we used this 340 00:23:34,400 --> 00:23:31,030 experimental data and model t how the 341 00:23:39,960 --> 00:23:34,410 product and the remaining associations 342 00:23:42,240 --> 00:23:39,970 in this diagram as a function of so2 343 00:23:47,520 --> 00:23:42,250 partial pressure and co partial pressure 344 00:23:52,800 --> 00:23:47,530 and we conclude that about one percent 345 00:23:54,840 --> 00:23:52,810 of the carbon monoxide is present in the 346 00:24:00,750 --> 00:23:54,850 atmosphere we can be produced this group 347 00:24:05,040 --> 00:24:00,760 or methane hydrogen also in the 348 00:24:09,780 --> 00:24:05,050 candidate so as I mentioned earlier the 349 00:24:14,820 --> 00:24:09,790 TM Aaron sir is not a pure co2 of course 350 00:24:18,450 --> 00:24:14,830 and moral reducing than previous results 351 00:24:20,320 --> 00:24:18,460 and possibly including one person amount 352 00:24:26,560 --> 00:24:20,330 of CO or methane 353 00:24:29,799 --> 00:24:26,570 or hydrogen ok so the question is this 354 00:24:36,639 --> 00:24:29,809 sort of high CO out of ashtrays possible 355 00:24:40,149 --> 00:24:36,649 or not sure answer is yes and because 356 00:24:43,180 --> 00:24:40,159 the co2 is always photo eyes in to see 357 00:24:46,210 --> 00:24:43,190 you and oxygen but that Buckley action 358 00:24:50,159 --> 00:24:46,220 CU plus 0 into co2 this is spin forward 359 00:24:54,909 --> 00:24:50,169 reaction so very very very slow the only 360 00:24:58,180 --> 00:24:54,919 think reaction of co is the reaction 361 00:25:00,759 --> 00:24:58,190 between OS radical a hydroxyl radical 362 00:25:05,529 --> 00:25:00,769 that it is formed by the photoresist 363 00:25:08,289 --> 00:25:05,539 water so that's why at least a upper 364 00:25:11,740 --> 00:25:08,299 part of the atmosphere here to adam see 365 00:25:16,659 --> 00:25:11,750 the column on auction is in labor is 366 00:25:19,889 --> 00:25:16,669 increasing and but if the atmosphere 367 00:25:23,399 --> 00:25:19,899 contain or the system contained in a 368 00:25:26,590 --> 00:25:23,409 sufficient amount of the reducing agent 369 00:25:30,490 --> 00:25:26,600 CEO can be sometimes accumulated in the 370 00:25:34,899 --> 00:25:30,500 ionosphere and this one-dimensional 371 00:25:37,810 --> 00:25:34,909 model should if the hydrogen molecular 372 00:25:44,049 --> 00:25:37,820 hydrogen level is high our CEO level 373 00:25:46,750 --> 00:25:44,059 might can be exceeded against the co so 374 00:25:50,889 --> 00:25:46,760 the key question is where the reducing 375 00:25:54,879 --> 00:25:50,899 agent came from the hydrogen or i think 376 00:26:00,669 --> 00:25:54,889 the most likely abundant reducing agent 377 00:26:02,919 --> 00:26:00,679 is iron two-plus ferrous ion is always 378 00:26:07,690 --> 00:26:02,929 supplied by the harder so Monica Vitti 379 00:26:10,360 --> 00:26:07,700 and the event so i am not talk about the 380 00:26:14,379 --> 00:26:10,370 process between our ocean ocean and bent 381 00:26:18,730 --> 00:26:14,389 but in terms of the budget you know the 382 00:26:21,810 --> 00:26:18,740 eye on fox is large enough to scavenging 383 00:26:29,049 --> 00:26:21,820 this oh h that is oxidizing fear into 384 00:26:34,049 --> 00:26:29,059 co2 so as a result if the ion is not 385 00:26:39,730 --> 00:26:37,810 iron oxide is precipitating in fact you 386 00:26:44,680 --> 00:26:39,740 can see a lot of fun in iron formation 387 00:26:46,600 --> 00:26:44,690 in the arcane period so now let's go 388 00:26:48,759 --> 00:26:46,610 back to this slide we can monitor 389 00:26:55,960 --> 00:26:48,769 reducing gas MO and the volcanic 390 00:26:59,590 --> 00:26:55,970 activity should is two things of the 391 00:27:03,340 --> 00:26:59,600 isotopic anomaly and if our molar is 392 00:27:07,870 --> 00:27:03,350 collect the body asian or magnitude of 393 00:27:10,960 --> 00:27:07,880 this scatter means the volcanic activity 394 00:27:13,960 --> 00:27:10,970 the large valuation means the higher 395 00:27:17,830 --> 00:27:13,970 volcanic activity smaller a variation in 396 00:27:20,080 --> 00:27:17,840 the global connect activity and if we 397 00:27:22,990 --> 00:27:20,090 look at the slow pitch in the true 398 00:27:25,509 --> 00:27:23,000 anomaly the shallow slope means the 399 00:27:29,529 --> 00:27:25,519 reducing condition and the steep slope 400 00:27:33,519 --> 00:27:29,539 means oxidizing condition so we can at 401 00:27:35,860 --> 00:27:33,529 least say polite the archaean period 402 00:27:39,870 --> 00:27:35,870 behold great oxidation event at least in 403 00:27:43,330 --> 00:27:39,880 23 pot and other one sir can be 404 00:27:51,600 --> 00:27:43,340 fluctuated reducing oxygen reducing rate 405 00:27:53,740 --> 00:27:51,610 this ok and ok and this to time period 406 00:27:57,159 --> 00:27:53,750 correspond to the higher volcanic 407 00:28:00,120 --> 00:27:57,169 activity at that time at the same time 408 00:28:03,840 --> 00:28:00,130 they are the most serious reducing and 409 00:28:07,090 --> 00:28:03,850 this is consistent with the previous 410 00:28:10,779 --> 00:28:07,100 geological liquid this is a figure show 411 00:28:14,159 --> 00:28:10,789 the college age distribution of the body 412 00:28:17,590 --> 00:28:14,169 ryan formation that make implies the 413 00:28:22,149 --> 00:28:17,600 higher harder form of rocks of iron into 414 00:28:25,029 --> 00:28:22,159 the ocean yes as abundant as in the days 415 00:28:27,399 --> 00:28:25,039 and the problem and also the oxide ball 416 00:28:30,850 --> 00:28:27,409 carriers that are the age population 417 00:28:33,490 --> 00:28:30,860 planet is still strong so the late 418 00:28:35,950 --> 00:28:33,500 archaean period after two point seven 419 00:28:38,649 --> 00:28:35,960 five billion years ago as a higher 420 00:28:41,260 --> 00:28:38,659 brokerage account activity and also how 421 00:28:43,830 --> 00:28:41,270 to some activity and providing a 422 00:28:48,609 --> 00:28:43,840 reducing agent and auto most return 423 00:28:54,009 --> 00:28:48,619 reducing so back to this slide I like to 424 00:28:55,570 --> 00:28:54,019 say so the water lock reaction threw 425 00:28:58,479 --> 00:28:55,580 harder some of the action is very very 426 00:29:03,249 --> 00:28:58,489 very important not only for ocean but 427 00:29:06,759 --> 00:29:03,259 also atmosphere so I'd like to say you 428 00:29:10,509 --> 00:29:06,769 know this figures the misleading to 429 00:29:13,989 --> 00:29:10,519 consider the how the chemistry 430 00:29:18,629 --> 00:29:13,999 automotion all done can change you know 431 00:29:22,269 --> 00:29:18,639 the indiana t we have to see like this 432 00:29:24,639 --> 00:29:22,279 you know else is the low key planet so 433 00:29:27,810 --> 00:29:24,649 the ocean bottom is already 0.02 per 434 00:29:30,339 --> 00:29:27,820 cell it's easily buffered by rock 435 00:29:33,310 --> 00:29:30,349 through the water log reaction that is 436 00:29:36,669 --> 00:29:33,320 weathering her summer reaction and also 437 00:29:40,269 --> 00:29:36,679 both albums face only 0.0004 percents 438 00:29:45,219 --> 00:29:40,279 okay to me it's easy to change by the 439 00:29:46,869 --> 00:29:45,229 reaction between the war the locks so we 440 00:29:51,070 --> 00:29:46,879 have to consider about the link between 441 00:29:53,710 --> 00:29:51,080 Jesus for an atmosphere emotion and also 442 00:29:58,810 --> 00:29:53,720 this might be linked with the climate 443 00:30:02,639 --> 00:29:58,820 and this period is we can I didn't 444 00:30:05,830 --> 00:30:02,649 expand this blue lines the potential 445 00:30:08,019 --> 00:30:05,840 glaciation event this is pongola this is 446 00:30:13,989 --> 00:30:08,029 both Solana this is from southern India 447 00:30:17,409 --> 00:30:13,999 we found addition tree and okay future 448 00:30:20,409 --> 00:30:17,419 is not the major component to counter 449 00:30:23,379 --> 00:30:20,419 the climber over temperature and the 450 00:30:27,489 --> 00:30:23,389 other videos in gases is important you 451 00:30:30,039 --> 00:30:27,499 know the co2 capture the window region 452 00:30:34,210 --> 00:30:30,049 of the ir emission that escaped into 453 00:30:38,070 --> 00:30:34,220 space but equal amount of energy can 454 00:30:41,109 --> 00:30:38,080 absorb the only 1 ppm of the methane or 455 00:30:43,330 --> 00:30:41,119 the other guests psychosis can be 456 00:30:45,759 --> 00:30:43,340 produced is under the cereal each animal 457 00:30:48,070 --> 00:30:45,769 field so we have to think about more 458 00:30:52,239 --> 00:30:48,080 tourists gasp but trace gas is not 459 00:30:54,140 --> 00:30:52,249 trivial to consider the temperature of 460 00:31:07,100 --> 00:30:54,150 the 461 00:31:19,820 --> 00:31:10,260 so we are happy to accept your questions 462 00:31:22,980 --> 00:31:19,830 or comments yeah the 2.7 the increased 463 00:31:26,310 --> 00:31:22,990 volcanism is that could you interpret it 464 00:31:28,560 --> 00:31:26,320 as increased so2 volcanism and not just 465 00:31:29,880 --> 00:31:28,570 I mean could be the change in the gases 466 00:31:33,270 --> 00:31:29,890 that volcanoes are putting up rather 467 00:31:37,760 --> 00:31:33,280 than a Vulcan AMA tree in general that's 468 00:31:44,670 --> 00:31:37,770 yeah that's very interesting why but i 469 00:31:48,470 --> 00:31:44,680 think the yeah oxide volcanism the 470 00:31:53,460 --> 00:31:48,480 several area of volcanism tend to and 471 00:31:56,450 --> 00:31:53,470 how much more effort to compare to h2s 472 00:32:02,930 --> 00:31:56,460 because the pressure the lower pressure 473 00:32:06,030 --> 00:32:02,940 the so2 leader is compared to non so2 474 00:32:11,490 --> 00:32:06,040 h2s ratio of the volcanic gas is 475 00:32:15,570 --> 00:32:11,500 increased on the roof yes low pressure 476 00:32:19,680 --> 00:32:15,580 so sub area of all kinds like island of 477 00:32:22,890 --> 00:32:19,690 volcanism it's responsible for that so 478 00:32:25,950 --> 00:32:22,900 yeah if we look at the you know the 479 00:32:28,230 --> 00:32:25,960 seafloor volcanism we can see different 480 00:32:39,279 --> 00:32:28,240 pictures so that's interesting point I 481 00:32:43,729 --> 00:32:41,299 just a question again about the 482 00:32:45,320 --> 00:32:43,739 volcanism is there a reason you chose 483 00:32:48,590 --> 00:32:45,330 not to think about large igneous 484 00:32:51,499 --> 00:32:48,600 province volcanism to those fissures 485 00:32:52,580 --> 00:32:51,509 back then at least if you predict how 486 00:32:55,399 --> 00:32:52,590 high they go they put a lot of 487 00:33:00,769 --> 00:32:55,409 stratospheric so2 into the exosphere 488 00:33:05,419 --> 00:33:00,779 would be yeah but we don't know much 489 00:33:08,479 --> 00:33:05,429 about that so you know och workers emit 490 00:33:13,700 --> 00:33:08,489 more much more institute compared to non 491 00:33:17,090 --> 00:33:13,710 special type I guess but not canale 492 00:33:23,019 --> 00:33:17,100 lucky right the eyes the example we have 493 00:33:25,820 --> 00:33:23,029 recently lucky lucky option hmm yeah so 494 00:33:29,029 --> 00:33:25,830 yeah large igneous province also 495 00:33:39,190 --> 00:33:29,039 increase at played rock n time but you 496 00:33:45,289 --> 00:33:39,200 know this type of yeah comparison is 497 00:33:48,409 --> 00:33:45,299 still its base so yeah yeah I like to 498 00:33:50,450 --> 00:33:48,419 compare with that you know age 499 00:33:53,269 --> 00:33:50,460 distribution large even in scoring 500 00:34:04,060 --> 00:33:53,279 students but yeah if you have there you 501 00:34:10,970 --> 00:34:07,009 similar question but I'm little confused 502 00:34:14,389 --> 00:34:10,980 at how reduced the volcanic gas because 503 00:34:16,339 --> 00:34:14,399 the this picture is very clear that my 504 00:34:18,349 --> 00:34:16,349 question is how reducible can I guess 505 00:34:20,559 --> 00:34:18,359 and if you don't have a reaction with 506 00:34:24,940 --> 00:34:20,569 the height of some activities and then 507 00:34:29,299 --> 00:34:24,950 could you make you reduce the atmosphere 508 00:34:33,730 --> 00:34:29,309 you know assuming the the mountain 509 00:34:37,129 --> 00:34:33,740 lyrics state that's buffer likely ahem 510 00:34:42,580 --> 00:34:37,139 omaha beach and then the volcanic gets 511 00:34:46,550 --> 00:34:42,590 to be donated by h2 and then co2 512 00:34:51,649 --> 00:34:46,560 but the addition of co2 is not you know 513 00:34:54,200 --> 00:34:51,659 i think is trivial because if the point 514 00:34:58,160 --> 00:34:54,210 one ball field is already available in 515 00:35:03,310 --> 00:34:58,170 the LOC so but the interaction between 516 00:35:06,980 --> 00:35:03,320 you know this is fear and hydrosphere 517 00:35:08,630 --> 00:35:06,990 atmosphere is two types one is director 518 00:35:10,220 --> 00:35:08,640 you know addition of gases by the 519 00:35:13,250 --> 00:35:10,230 volcanic rocks dude this is high 520 00:35:16,490 --> 00:35:13,260 temperature process but as I actually 521 00:35:17,780 --> 00:35:16,500 mention one more lower temperature you 522 00:35:20,270 --> 00:35:17,790 know introduction that is the 523 00:35:25,960 --> 00:35:20,280 hydrothermal you know circulation and 524 00:35:28,400 --> 00:35:25,970 also weatherly of continent or mercy for 525 00:35:34,670 --> 00:35:28,410 that should be taken into account that 526 00:35:37,340 --> 00:35:34,680 is my what I'm trying to say yeah if you 527 00:35:39,890 --> 00:35:37,350 mean at least of even have any ocean 528 00:35:41,930 --> 00:35:39,900 surface water you didn't you couldn't 529 00:35:46,160 --> 00:35:41,940 have any so I hydrofarm activities and 530 00:35:49,730 --> 00:35:46,170 then but you have enough you mean no 531 00:35:51,680 --> 00:35:49,740 order but like Mark like Mars and if you 532 00:35:54,710 --> 00:35:51,690 don't have any water on the surface and 533 00:36:02,480 --> 00:35:54,720 then volcanic activities could not 534 00:36:06,290 --> 00:36:02,490 produce the videos atmosphere right yeah 535 00:36:08,990 --> 00:36:06,300 it's yeah I only said that in terms of 536 00:36:13,520 --> 00:36:09,000 budget but I don't argue that you know 537 00:36:17,870 --> 00:36:13,530 the mechanism so yeah that's it I think 538 00:36:21,590 --> 00:36:17,880 it's in for interfering and our war is a 539 00:36:25,400 --> 00:36:21,600 very good medium to faceted the action I 540 00:36:31,070 --> 00:36:25,410 think so yeah I can't imagine so for 541 00:36:34,600 --> 00:36:31,080 that yeah it's interesting question can 542 00:36:38,030 --> 00:36:34,610 I ask you a naive question so can you 543 00:36:40,340 --> 00:36:38,040 extrapolate some part of Hadean 544 00:36:43,700 --> 00:36:40,350 atomosphere hidden environment from your 545 00:36:56,720 --> 00:36:52,550 mm-hmm just yeah very difficult but yeah 546 00:37:01,070 --> 00:36:56,730 it depends on the model so after how 547 00:37:07,910 --> 00:37:01,080 fast the unit like are very show the 548 00:37:10,780 --> 00:37:07,920 first day and how fast do you know the 549 00:37:15,890 --> 00:37:10,790 CEO to leave is buffered by did you know 550 00:37:18,410 --> 00:37:15,900 the several processes and yeah we can 551 00:37:21,680 --> 00:37:18,420 provide the one you know boundary 552 00:37:26,329 --> 00:37:21,690 conditions so I think it depends on the 553 00:37:29,690 --> 00:37:26,339 model if you know we don't have not much 554 00:37:33,230 --> 00:37:29,700 you know geological samples so your 555 00:37:47,660 --> 00:37:33,240 chemist doesn't say anything dielectric 556 00:37:54,620 --> 00:37:50,960 hey hey you true also possibly naive 557 00:37:56,930 --> 00:37:54,630 question but I was wondering if with the 558 00:37:59,500 --> 00:37:56,940 amount of so2 that you think is going to 559 00:38:02,690 --> 00:37:59,510 the atmosphere if that would connect to 560 00:38:06,020 --> 00:38:02,700 these big sulfate deposits that are 561 00:38:09,230 --> 00:38:06,030 found around 3.4 billion years ago these 562 00:38:14,990 --> 00:38:09,240 berries North Pole barite things yes I 563 00:38:26,829 --> 00:38:15,000 think so for not just some deposit yeah 564 00:38:33,920 --> 00:38:31,280 to produce a large isotopic anna-marie 565 00:38:38,420 --> 00:38:33,930 it needs the very dense or particular 566 00:38:42,500 --> 00:38:38,430 thickness of so2 but the lifetime so2 is 567 00:38:44,960 --> 00:38:42,510 very short as several years not merely 568 00:38:49,460 --> 00:38:44,970 anxious you know so that's why I think 569 00:38:55,940 --> 00:38:49,470 that are normally producing a process a 570 00:38:58,670 --> 00:38:55,950 very short of phenomena like after the 571 00:39:04,940 --> 00:38:58,680 volcanic eruption I hope for example 572 00:39:07,970 --> 00:39:04,950 yeah so several so faith deposit is may 573 00:39:12,170 --> 00:39:07,980 be related to just kind of you know what 574 00:39:16,130 --> 00:39:12,180 can a vent yes likely possibility i 575 00:39:30,270 --> 00:39:16,140 think and their goal should be can be 576 00:39:35,740 --> 00:39:33,880 yeah you have a picture of banded I 577 00:39:37,410 --> 00:39:35,750 information you have the letter e on top 578 00:39:39,550 --> 00:39:37,420 of it you say equals reducing atmosphere 579 00:39:41,440 --> 00:39:39,560 during when there is a reducing 580 00:39:43,120 --> 00:39:41,450 atmosphere what is it that the varying 581 00:39:44,680 --> 00:39:43,130 that's producing the stripes in the 582 00:39:47,220 --> 00:39:44,690 banded iron formation is it's of aqueous 583 00:39:50,340 --> 00:39:47,230 volcanism or something or what is it 584 00:39:54,850 --> 00:39:50,350 yeah that's a huge argument there is 585 00:40:00,850 --> 00:39:54,860 here you have a new one yeah it could be 586 00:40:04,810 --> 00:40:00,860 you know the part of the you know the 587 00:40:08,890 --> 00:40:04,820 periodic emission of the event that can 588 00:40:11,170 --> 00:40:08,900 create Bob like structure so that is one 589 00:40:14,470 --> 00:40:11,180 possibility okay intermittent emission 590 00:40:16,480 --> 00:40:14,480 of fe 2 from hydrothermal vent that is 591 00:40:21,220 --> 00:40:16,490 one possibility okay and then somebody 592 00:40:26,650 --> 00:40:21,230 says this is in annual you know like on 593 00:40:28,570 --> 00:40:26,660 a daily or year recycle but it's still 594 00:40:31,690 --> 00:40:28,580 controversial but it's possible to 595 00:40:34,480 --> 00:40:31,700 deflect in a periodic input a higher 596 00:40:37,420 --> 00:40:34,490 cement result and the other the other 597 00:40:40,740 --> 00:40:37,430 people who disagree with that say yeah 598 00:40:49,850 --> 00:40:40,750 they're long long you know debate yeah 599 00:40:58,160 --> 00:40:51,980 I'm sorry still have five more minutes 600 00:40:59,360 --> 00:40:58,170 what I have a question if possible hi I 601 00:41:01,820 --> 00:40:59,370 very much enjoyed your presentation 602 00:41:03,530 --> 00:41:01,830 thank you and thank you with some 603 00:41:05,330 --> 00:41:03,540 colleagues we would publish some work 604 00:41:07,850 --> 00:41:05,340 that suggests that air pressure at 605 00:41:10,040 --> 00:41:07,860 around 2.9 was less than modern right 606 00:41:12,500 --> 00:41:10,050 now wondering if that would magnify the 607 00:41:13,940 --> 00:41:12,510 effects of a sulfur injection to the 608 00:41:23,590 --> 00:41:13,950 atmosphere and would that be reflected 609 00:41:32,950 --> 00:41:26,300 it's not the magnifier that you know 610 00:41:36,800 --> 00:41:32,960 story is the same yeah but every if co2 611 00:41:39,550 --> 00:41:36,810 levels on one bar with 10 bar that's a 612 00:41:45,760 --> 00:41:39,560 totally different story so because the 613 00:41:48,710 --> 00:41:45,770 co2 is fielding they you know this 614 00:41:51,410 --> 00:41:48,720 wavelength region responsible for the 615 00:41:54,920 --> 00:41:51,420 so2 photoresist and excitation so it's 616 00:42:00,320 --> 00:41:54,930 highly highly relevant if total pressure 617 00:42:03,680 --> 00:42:00,330 be decided by co2 but if you know total 618 00:42:09,530 --> 00:42:03,690 pressure is changed by m2 G nitrogen 619 00:42:16,430 --> 00:42:09,540 that's invisible for me I can't get the 620 00:42:24,500 --> 00:42:16,440 elephant looks good thank you any other 621 00:42:28,250 --> 00:42:24,510 naive question hi Greta just want to ask 622 00:42:34,130 --> 00:42:28,260 you a you commented that the most 623 00:42:36,970 --> 00:42:34,140 important input to early Earth's 624 00:42:43,330 --> 00:42:36,980 atmosphere might have been the input / 625 00:42:48,710 --> 00:42:43,340 Ferris Aaron why do you think that the 626 00:42:50,780 --> 00:42:48,720 outgassing of reducing gases those 627 00:42:57,680 --> 00:42:50,790 fluxes should be smaller than Sarah 628 00:43:04,170 --> 00:43:00,560 that's simply because of the you know 629 00:43:08,910 --> 00:43:04,180 the estimated sucks and you know likely 630 00:43:11,670 --> 00:43:08,920 possibility but compared to reach one 631 00:43:14,130 --> 00:43:11,680 guy they are so you mentioned with a 632 00:43:17,730 --> 00:43:14,140 flat I just hangin on the level is 633 00:43:19,970 --> 00:43:17,740 mole's per year I just converted II know 634 00:43:24,060 --> 00:43:19,980 that is the present-day facts oh no 635 00:43:40,590 --> 00:43:24,070 value to modern Cecil okay as it could 636 00:43:44,710 --> 00:43:40,600 be higher than that yeah okay okay so