1 00:00:00,901 --> 00:00:00,966 NARRATOR: Explosions. 2 00:00:02,937 --> 00:00:04,570 Earthquakes. 3 00:00:04,572 --> 00:00:06,805 You guys all right? 4 00:00:08,142 --> 00:00:09,174 MAN: Would you get away from there?! 5 00:00:09,176 --> 00:00:10,843 NARRATOR: Lava in the streets. 6 00:00:10,845 --> 00:00:15,047 MAN: This is insane. 7 00:00:15,049 --> 00:00:18,917 NARRATOR: In 2018, Hawai'i experiences 8 00:00:18,919 --> 00:00:20,853 its most destructive volcanic eruption 9 00:00:20,855 --> 00:00:22,721 in over a quarter-century. 10 00:00:22,723 --> 00:00:26,291 MAN: Whoa! 11 00:00:26,293 --> 00:00:28,861 NARRATOR: Residents flee for their lives. 12 00:00:28,863 --> 00:00:30,362 WOMAN: We're packed, 13 00:00:30,364 --> 00:00:31,663 and we're evacuating. 14 00:00:31,665 --> 00:00:33,265 NARRATOR: As the Earth erupts 15 00:00:33,267 --> 00:00:35,367 beneath their homes. 16 00:00:35,369 --> 00:00:37,736 (women screaming) 17 00:00:37,738 --> 00:00:39,405 WOMAN: There was a house there. 18 00:00:39,407 --> 00:00:41,473 Yeah, it's gone, it's under the lava. 19 00:00:41,475 --> 00:00:42,574 NARRATOR: And nature turns 20 00:00:42,576 --> 00:00:43,942 a Hawaiian paradise 21 00:00:43,944 --> 00:00:45,944 into a vision of Hell. 22 00:00:45,946 --> 00:00:48,013 But through it all, 23 00:00:48,015 --> 00:00:50,249 scientists are on the front line. 24 00:00:50,251 --> 00:00:52,317 (bursting) 25 00:00:52,319 --> 00:00:54,653 Tracking subterranean magma flows. 26 00:00:54,655 --> 00:00:56,822 BRIAN SHIRO: Think of it like a sword 27 00:00:56,824 --> 00:00:59,024 cutting its way through the rock. 28 00:00:59,026 --> 00:01:02,261 NARRATOR: Risking exposure to toxic gases. 29 00:01:02,263 --> 00:01:04,329 You can actually see all the sulfur 30 00:01:04,331 --> 00:01:06,498 that is actually crystallizing. 31 00:01:06,500 --> 00:01:09,601 NARRATOR: And uncovering secrets held 32 00:01:09,603 --> 00:01:11,136 inside the molten rock. 33 00:01:11,138 --> 00:01:14,473 The chemistry was extremely evolved. 34 00:01:14,475 --> 00:01:15,841 NARRATOR: All to answer 35 00:01:15,843 --> 00:01:18,210 the question on everyone's mind: 36 00:01:18,212 --> 00:01:20,746 How bad will it get? 37 00:01:20,748 --> 00:01:23,015 RYAN PERROY: Very quickly, it became of a scale and magnitude 38 00:01:23,017 --> 00:01:25,417 greater than what we were able to handle. 39 00:01:27,421 --> 00:01:31,490 NARRATOR: "Kilauea: Hawai'i on Fire." 40 00:01:31,492 --> 00:01:34,626 Right now, on "NOVA." 41 00:01:34,628 --> 00:01:38,764 ♪ ♪ 42 00:01:41,168 --> 00:01:43,368 NARRATOR: In 2018, the island of Hawai'i 43 00:01:43,370 --> 00:01:45,204 becomes a living hell. 44 00:01:45,206 --> 00:01:49,108 Locals rush for their lives 45 00:01:49,110 --> 00:01:52,144 as red-hot lava bursts from under their houses. 46 00:01:52,146 --> 00:01:53,745 MAN: This is-- I don't know, man! 47 00:01:53,747 --> 00:01:56,615 NARRATOR: Fountaining hundreds of feet into the air. 48 00:01:56,617 --> 00:01:58,550 (woman calling out) 49 00:01:58,552 --> 00:02:00,452 MAN: We need medical assistance here! 50 00:02:00,454 --> 00:02:06,024 NARRATOR: It's an eruption on a scale not seen for a generation. 51 00:02:06,026 --> 00:02:09,428 450 earthquakes in just the last 24 hours. 52 00:02:14,034 --> 00:02:16,235 NARRATOR: Upending the lives of thousands 53 00:02:16,237 --> 00:02:20,239 and transforming the landscape of Hawai'i. 54 00:02:21,142 --> 00:02:22,407 But while residents evacuate, 55 00:02:22,409 --> 00:02:25,077 scientists head into the field, 56 00:02:25,079 --> 00:02:26,245 tracking the action 57 00:02:26,247 --> 00:02:29,314 to discover what may be next. 58 00:02:29,316 --> 00:02:31,950 How accurate are their predictions? 59 00:02:31,952 --> 00:02:34,019 We knew it was not if, but when. 60 00:02:34,021 --> 00:02:36,388 NARRATOR: Is this the start of a new period 61 00:02:36,390 --> 00:02:38,690 of dangerous volcanic activity? 62 00:02:38,692 --> 00:02:40,559 STACY WELCH: This is unstoppable. 63 00:02:40,561 --> 00:02:42,427 This is epic. 64 00:02:42,429 --> 00:02:44,863 NARRATOR: And what does it tell us 65 00:02:44,865 --> 00:02:48,167 about the true nature of the iconic islands of Hawai'i? 66 00:02:48,169 --> 00:02:51,203 (rumbling) 67 00:02:55,609 --> 00:02:59,778 2,400 miles to the southwest of the U.S. mainland 68 00:02:59,780 --> 00:03:02,314 lies the Hawaiian archipelago, 69 00:03:02,316 --> 00:03:04,082 a chain of tropical islands 70 00:03:04,084 --> 00:03:05,984 covered in lush rainforest 71 00:03:05,986 --> 00:03:09,421 and home to vibrant wildlife. 72 00:03:09,423 --> 00:03:12,658 It's America's paradise in the Pacific, 73 00:03:12,660 --> 00:03:14,993 and a mecca for tourists. 74 00:03:17,164 --> 00:03:21,567 But the 50th state is more than just sun, sand, and surf. 75 00:03:21,569 --> 00:03:24,603 (water splashing) 76 00:03:24,605 --> 00:03:29,408 On the southern part of the southernmost island 77 00:03:29,410 --> 00:03:32,711 lies Kilauea, an active volcano 78 00:03:32,713 --> 00:03:35,514 within the Hawai'i Volcanoes National Park. 79 00:03:35,516 --> 00:03:39,551 Lava is visible in a small lake at the summit 80 00:03:39,553 --> 00:03:43,255 and at Pu'u 'O'o, a seeping vent 81 00:03:43,257 --> 00:03:46,625 on the flank of the mountain. 82 00:03:46,627 --> 00:03:48,493 Both sites are popular with tourists 83 00:03:48,495 --> 00:03:50,596 and constantly monitored 84 00:03:50,598 --> 00:03:54,600 by a team of on-site volcanologists. 85 00:03:54,602 --> 00:03:55,901 But in April 2018, 86 00:03:55,903 --> 00:03:59,571 the scientists of the Hawaiian Volcano Observatory 87 00:03:59,573 --> 00:04:03,475 become concerned about rising levels of lava. 88 00:04:03,477 --> 00:04:07,079 We had a situation where the lava lake at the summit 89 00:04:07,081 --> 00:04:10,415 was high, higher than it had been for quite a while, 90 00:04:10,417 --> 00:04:13,819 and in fact, it was periodically beginning to overflow. 91 00:04:13,821 --> 00:04:17,155 At the same time, the lava level within the Pu'u 'O'o vent 92 00:04:17,157 --> 00:04:19,324 was also very high. 93 00:04:19,326 --> 00:04:20,425 One of the things we've learned 94 00:04:20,427 --> 00:04:22,361 is that the magmatic system, 95 00:04:22,363 --> 00:04:23,662 the plumbing system is connected. 96 00:04:24,598 --> 00:04:27,432 NARRATOR: Magma is underground lava. 97 00:04:27,434 --> 00:04:30,469 Both lava lakes are fed from the same deep magma chamber 98 00:04:30,471 --> 00:04:33,205 lying miles below the summit. 99 00:04:33,207 --> 00:04:35,941 They act like pressure gauges. 100 00:04:35,943 --> 00:04:38,243 The recent high levels of the lakes 101 00:04:38,245 --> 00:04:39,911 are an indication 102 00:04:39,913 --> 00:04:42,547 that magma is building up under the volcano. 103 00:04:43,884 --> 00:04:46,151 NEAL: The magmatic pressure within the volcano was high. 104 00:04:46,153 --> 00:04:48,654 This meant there could be a change coming, 105 00:04:48,656 --> 00:04:51,189 although we weren't quite sure the nature of that change. 106 00:04:52,593 --> 00:04:57,929 NARRATOR: On April 30, that change arrives with shocking speed. 107 00:05:00,401 --> 00:05:01,933 In a matter of hours, 108 00:05:01,935 --> 00:05:05,270 all the lava in the Pu'u 'O'o vent disappears, 109 00:05:05,272 --> 00:05:09,207 leaving a gaping hole. 110 00:05:09,209 --> 00:05:11,877 It catches the volcanologists off-guard. 111 00:05:11,879 --> 00:05:13,278 NEAL: We were a little surprised. 112 00:05:13,280 --> 00:05:16,148 Past events at Pu'u 'O'o have seen collapses, 113 00:05:16,150 --> 00:05:19,051 short-term collapses, but none as deep as this one. 114 00:05:19,053 --> 00:05:22,621 NARRATOR: Almost 60 million tons of red-hot lava 115 00:05:22,623 --> 00:05:23,622 have just gone missing. 116 00:05:23,624 --> 00:05:26,958 The scientists have to find it, 117 00:05:26,960 --> 00:05:30,796 and they fear the worst when the ground begins to shake. 118 00:05:30,798 --> 00:05:35,233 (rumbling) 119 00:05:35,235 --> 00:05:37,069 The seismograms were off the charts, 120 00:05:37,071 --> 00:05:40,439 and, you know, I knew something big was happening. 121 00:05:42,009 --> 00:05:44,209 NARRATOR: Brian Shiro is a seismologist 122 00:05:44,211 --> 00:05:46,845 with the Hawaiian Volcano Observatory. 123 00:05:46,847 --> 00:05:49,381 He monitors a network of around 80 earthquake detectors 124 00:05:49,383 --> 00:05:51,316 positioned around the volcano. 125 00:05:53,687 --> 00:05:56,054 When Pu'u 'O'o's lava disappears, 126 00:05:56,056 --> 00:05:58,924 the network lights up. 127 00:05:58,926 --> 00:06:01,393 Around the vent, the land is being shaken 128 00:06:01,395 --> 00:06:05,197 by a swarm of tiny tremors. 129 00:06:05,199 --> 00:06:09,167 A swarm of earthquakes is a grouping of earthquakes 130 00:06:09,169 --> 00:06:10,969 close together in space and time. 131 00:06:10,971 --> 00:06:14,072 Given the context of Pu'u 'O'o, there really was no question 132 00:06:14,074 --> 00:06:16,875 what this was related to. 133 00:06:18,345 --> 00:06:20,912 NARRATOR: Below the surface, pressure from the magma 134 00:06:20,914 --> 00:06:23,348 has suddenly fractured the surrounding rock, 135 00:06:23,350 --> 00:06:26,651 opening cracks that fill with magma, 136 00:06:26,653 --> 00:06:31,990 generating earthquakes and triggering more fractures. 137 00:06:31,992 --> 00:06:36,561 A blade-like intrusion of magma is tunneling east. 138 00:06:39,133 --> 00:06:40,832 SHIRO: Think of it like a sword 139 00:06:40,834 --> 00:06:42,234 that's traveling beneath the ground 140 00:06:42,236 --> 00:06:44,503 and cutting its way through the rock as it goes. 141 00:06:44,505 --> 00:06:48,607 (rock grinding) 142 00:06:51,178 --> 00:06:53,345 It was moving underground at a rate 143 00:06:53,347 --> 00:06:55,380 probably about as fast as you could walk. 144 00:06:55,382 --> 00:06:59,317 ♪ ♪ 145 00:06:59,319 --> 00:07:02,821 NARRATOR: The earthquakes indicate the Pu'u 'O'o magma 146 00:07:02,823 --> 00:07:05,957 is advancing down Kilauea's east rift, 147 00:07:05,959 --> 00:07:08,026 heading out of the national park, 148 00:07:08,028 --> 00:07:11,430 down towards the ocean 20 miles away. 149 00:07:11,432 --> 00:07:13,398 Directly in its path lie the homes 150 00:07:13,400 --> 00:07:15,834 of thousands of people. 151 00:07:18,338 --> 00:07:19,838 NEAL: It was possible that magma would move 152 00:07:19,840 --> 00:07:22,441 through the rift zone system and not erupt, 153 00:07:22,443 --> 00:07:24,676 but there was also a strong likelihood 154 00:07:24,678 --> 00:07:26,411 that it would eventually find its way to the surface. 155 00:07:27,714 --> 00:07:32,050 We decided we must inform the Civil Defense authorities. 156 00:07:32,052 --> 00:07:34,219 We may not have a lot of time for warning. 157 00:07:39,660 --> 00:07:41,193 (crashing) 158 00:07:41,195 --> 00:07:45,130 NARRATOR: For 48 hours, the earthquakes have moved east. 159 00:07:45,132 --> 00:07:47,365 But suddenly they stop. 160 00:07:47,367 --> 00:07:51,203 The magma is changing direction. 161 00:07:51,205 --> 00:07:53,572 If the magma stops moving sideways, 162 00:07:53,574 --> 00:07:55,407 yet there's still pressure pushing it, 163 00:07:55,409 --> 00:07:56,608 it's going to have to go somewhere. 164 00:07:56,610 --> 00:07:59,978 NARRATOR: The magma is creeping upwards. 165 00:07:59,980 --> 00:08:01,446 Above lies Leilani Estates, 166 00:08:01,448 --> 00:08:06,718 a sleepy neighborhood about to have a rude awakening. 167 00:08:11,425 --> 00:08:14,693 The local Civil Defense agency puts everyone on alert. 168 00:08:14,695 --> 00:08:17,162 MAN (on radio): This is a Civil Defense message. 169 00:08:17,164 --> 00:08:18,997 An eruption is possible. 170 00:08:18,999 --> 00:08:20,665 BILL HANSON: We were getting reports 171 00:08:20,667 --> 00:08:23,134 that there was a lot of earthquake activity. 172 00:08:23,136 --> 00:08:26,238 MAN (on radio): Prepare in case of the need for evacuation. 173 00:08:26,240 --> 00:08:28,206 We were hoping for the best, 174 00:08:28,208 --> 00:08:29,941 but we were planning for the worst. 175 00:08:29,943 --> 00:08:33,111 NARRATOR: As the ground continues to shake, 176 00:08:33,113 --> 00:08:36,414 residents soon see their neighborhood is in trouble. 177 00:08:36,416 --> 00:08:37,816 WOMAN: Here is the crack, 178 00:08:37,818 --> 00:08:40,886 just right after the community center 179 00:08:40,888 --> 00:08:43,154 and the playground. 180 00:08:43,156 --> 00:08:44,289 I don't know if you can see that. 181 00:08:44,291 --> 00:08:46,358 There's my hand. 182 00:08:46,360 --> 00:08:50,195 NARRATOR: The cracks grow in size and number. 183 00:08:51,365 --> 00:08:52,731 WOMAN: This is new, 184 00:08:52,733 --> 00:08:54,232 coming out of there. 185 00:08:54,234 --> 00:08:59,604 NARRATOR: And steam begins to billow from the depths. 186 00:08:59,606 --> 00:09:01,106 At that point, we were fairly certain. 187 00:09:02,042 --> 00:09:04,175 We knew that it was not if, but when. 188 00:09:04,177 --> 00:09:07,178 NARRATOR: At 5 p.m. on May 3, 189 00:09:07,180 --> 00:09:10,615 the ground opens and the nightmare begins. 190 00:09:10,617 --> 00:09:11,716 (barking) 191 00:09:13,220 --> 00:09:15,954 (bang echoes) 192 00:09:20,427 --> 00:09:21,693 WOMAN: Oh, my God. 193 00:09:21,695 --> 00:09:24,963 We're packed and we're evacuating. 194 00:09:24,965 --> 00:09:29,301 NARRATOR: The eruption quickly becomes international news. 195 00:09:29,303 --> 00:09:33,939 A part of Hawai'i is under a mandatory evacuation. 196 00:09:33,941 --> 00:09:35,707 This right here is a residential area 197 00:09:35,709 --> 00:09:38,376 about 30 kilometers from Mt. Kilauea, 198 00:09:38,378 --> 00:09:42,781 and lava is being thrown up in the middle of the road. 199 00:09:42,783 --> 00:09:44,049 Authorities have ordered 200 00:09:44,051 --> 00:09:47,586 more than 1,700 people to leave immediately. 201 00:09:47,588 --> 00:09:49,487 I heard this roar. 202 00:09:49,489 --> 00:09:53,191 Almost like a fire-breathing dragon sort of a noise. 203 00:09:53,193 --> 00:09:55,460 It's the birth of a fissure. 204 00:09:55,462 --> 00:09:57,028 (banging) 205 00:09:57,030 --> 00:10:02,467 NARRATOR: One by one, fissures are opening up. 206 00:10:02,469 --> 00:10:05,637 Over the next few days, 207 00:10:05,639 --> 00:10:08,106 the neighborhood is ripped apart. 208 00:10:08,108 --> 00:10:09,808 (banging) 209 00:10:09,810 --> 00:10:15,547 MAN: This is freakin'-- I don't know, man. 210 00:10:15,549 --> 00:10:18,083 (weeping): I've been crying all morning. 211 00:10:18,085 --> 00:10:22,220 (lava churns) 212 00:10:23,991 --> 00:10:28,426 NARRATOR: Lava is now pouring over the land... 213 00:10:28,428 --> 00:10:30,128 (hissing) 214 00:10:30,130 --> 00:10:33,832 ...generating multiple flows that advance across roads... 215 00:10:35,402 --> 00:10:37,135 MAN: Would you get away from there?! 216 00:10:38,605 --> 00:10:40,772 NARRATOR: ...and into homes. 217 00:10:40,774 --> 00:10:43,074 (gate rattling) 218 00:10:43,076 --> 00:10:47,045 They are slow-moving, but relentless. 219 00:10:47,047 --> 00:10:50,181 What a flow doesn't bury, 220 00:10:50,183 --> 00:10:52,150 it sets on fire. 221 00:10:52,152 --> 00:10:54,986 (fire crackling) 222 00:10:54,988 --> 00:10:57,188 Even as it blackens and solidifies, 223 00:10:57,190 --> 00:10:59,491 it's over 1,000 degrees Fahrenheit. 224 00:10:59,493 --> 00:11:01,960 MAN: Burning its way through the pavement. 225 00:11:01,962 --> 00:11:06,698 (fire crackling) 226 00:11:08,535 --> 00:11:09,701 NARRATOR: Across the neighborhood, 227 00:11:09,703 --> 00:11:11,970 residents are evacuating. 228 00:11:11,972 --> 00:11:14,272 REPORTER: When you finally do get back home, 229 00:11:14,274 --> 00:11:16,241 what will you find? 230 00:11:16,243 --> 00:11:18,576 (chuckling): Ashes. It's ashes. 231 00:11:18,578 --> 00:11:23,948 ♪ ♪ 232 00:11:26,186 --> 00:11:29,087 NARRATOR: It's now over a week since the fissures opened, 233 00:11:29,089 --> 00:11:30,922 and the eruption continues. 234 00:11:33,794 --> 00:11:35,994 To gauge the extent of the lava flow, 235 00:11:35,996 --> 00:11:39,197 volcanologist Sam Mitchell from the University of Hawai'i 236 00:11:39,199 --> 00:11:41,232 is going in for a closer look. 237 00:11:43,770 --> 00:11:45,970 It's really quite something, to be able to watch it, 238 00:11:45,972 --> 00:11:47,505 and especially to see it from up above. 239 00:11:47,507 --> 00:11:51,309 ♪ ♪ 240 00:11:51,311 --> 00:11:55,246 NARRATOR: 15 fissures have now erupted, 241 00:11:55,248 --> 00:12:01,152 spewing out enough lava to cover 88 football fields. 242 00:12:01,154 --> 00:12:04,022 It's clear that all the fissures originate 243 00:12:04,024 --> 00:12:06,891 from the same thin, deep crack in the Earth. 244 00:12:10,397 --> 00:12:11,930 At the moment, all the fissures 245 00:12:11,932 --> 00:12:13,798 are erupting along one single line, 246 00:12:13,800 --> 00:12:17,802 but the lava flows can then spread laterally either side, 247 00:12:17,804 --> 00:12:19,838 and that's the biggest danger. 248 00:12:19,840 --> 00:12:22,040 It's difficult to know which fissures 249 00:12:22,042 --> 00:12:23,908 will produce large flows 250 00:12:23,910 --> 00:12:27,612 and how far those flows will actually go. 251 00:12:27,614 --> 00:12:29,948 This really is an evolving story. 252 00:12:29,950 --> 00:12:33,952 (rumbling and crackling) 253 00:12:33,954 --> 00:12:38,089 NARRATOR: But now the flows appear to be slowing. 254 00:12:38,091 --> 00:12:40,792 After a week of activity, 255 00:12:40,794 --> 00:12:43,728 many of the original fissures around Leilani Estates 256 00:12:43,730 --> 00:12:46,131 are sputtering to a halt. 257 00:12:46,133 --> 00:12:49,667 Bill Hanson's Civil Defense team notices the change. 258 00:12:49,669 --> 00:12:52,537 There was spattering, yes, there was noise, yes, 259 00:12:52,539 --> 00:12:57,242 but there wasn't any flow; the lava was very static. 260 00:12:57,244 --> 00:12:58,977 NARRATOR: After a week of chaos, 261 00:12:58,979 --> 00:13:01,312 could the eruption be winding down? 262 00:13:01,314 --> 00:13:05,450 The only way to find out is a risky scramble 263 00:13:05,452 --> 00:13:07,285 to sample the lava. 264 00:13:10,657 --> 00:13:13,324 (splashing) 265 00:13:13,326 --> 00:13:15,894 Getting up-close and personal to a lava flow 266 00:13:15,896 --> 00:13:18,163 is not for the faint-hearted. 267 00:13:18,165 --> 00:13:19,631 But for researchers 268 00:13:19,633 --> 00:13:24,135 like University of Hawai'i volcanologist Cheryl Gansecki, 269 00:13:24,137 --> 00:13:26,938 what lava can reveal about the status of the eruption 270 00:13:26,940 --> 00:13:29,307 is worth the risk. 271 00:13:29,309 --> 00:13:32,877 We would put out tubs to try to catch some lava 272 00:13:32,879 --> 00:13:33,945 falling out of the sky. 273 00:13:33,947 --> 00:13:36,481 You really go as fast as you can 274 00:13:36,483 --> 00:13:37,816 and hope you've grabbed enough material, 275 00:13:37,818 --> 00:13:39,884 so you don't have to do it again. 276 00:13:42,055 --> 00:13:43,221 NARRATOR: Back at the lab, 277 00:13:43,223 --> 00:13:45,223 the investigation can begin. 278 00:13:45,225 --> 00:13:48,359 The University of Hawai'i has built a database 279 00:13:48,361 --> 00:13:50,728 of lavas collected from previous eruptions 280 00:13:50,730 --> 00:13:54,299 and created a high-speed method of identification. 281 00:13:56,803 --> 00:13:58,102 (rattling) 282 00:13:58,104 --> 00:13:59,537 Crushing samples from the new flows 283 00:13:59,539 --> 00:14:01,606 into a fine powder 284 00:14:01,608 --> 00:14:04,976 allows an analysis of their ingredients. 285 00:14:06,012 --> 00:14:09,280 All lava has a fingerprint. 286 00:14:09,282 --> 00:14:11,816 Subtle differences in chemical composition 287 00:14:11,818 --> 00:14:16,654 allow volcanologists to determine its origins. 288 00:14:19,626 --> 00:14:22,293 The results are a surprise. 289 00:14:22,295 --> 00:14:26,965 The lava erupting at Leilani is not the same as the lava 290 00:14:26,967 --> 00:14:31,536 that disappeared from Pu'u 'O'o and headed down the mountain. 291 00:14:31,538 --> 00:14:36,374 But it is just like lava that they've seen before. 292 00:14:36,376 --> 00:14:39,110 GANSECKI: It was very similar in character 293 00:14:39,112 --> 00:14:41,446 to another eruption 294 00:14:41,448 --> 00:14:44,315 that had happened in that same area in 1955. 295 00:14:46,186 --> 00:14:47,919 MAN (on film): Two fissures, 296 00:14:47,921 --> 00:14:51,155 each about 300 feet long, emitting lava, 297 00:14:51,157 --> 00:14:54,893 extended from the Pohoiki Road into field 114. 298 00:14:54,895 --> 00:15:00,698 NARRATOR: In 1955, a massive eruption shook this part of the mountain. 299 00:15:00,700 --> 00:15:02,066 It lasted three months, 300 00:15:02,068 --> 00:15:05,236 with lava gushing from 24 separate vents. 301 00:15:08,642 --> 00:15:09,908 But evidently, 302 00:15:09,910 --> 00:15:13,478 not all the magma reached the surface 303 00:15:13,480 --> 00:15:17,015 before the eruptive pressure dropped. 304 00:15:17,017 --> 00:15:19,517 Cheryl's discovery suggests 305 00:15:19,519 --> 00:15:22,086 that the traveling Pu'u 'O'o lava 306 00:15:22,088 --> 00:15:25,924 encountered the remnants of the 1955 eruption, 307 00:15:25,926 --> 00:15:28,993 lying dormant for more than 60 years, 308 00:15:28,995 --> 00:15:31,029 the pressure from the fresh lava 309 00:15:31,031 --> 00:15:33,264 forcing it to the surface. 310 00:15:33,266 --> 00:15:36,134 Because this old magma is relatively cool, 311 00:15:36,136 --> 00:15:40,605 on contact with air, it solidifies quickly. 312 00:15:40,607 --> 00:15:43,574 But the fresh, hot lava from Pu'u 'O'o 313 00:15:43,576 --> 00:15:46,678 will be far more dynamic if it reaches the surface. 314 00:15:46,680 --> 00:15:51,816 This eruption isn't over-- it's only just begun. 315 00:15:51,818 --> 00:15:52,984 What everybody was worried about 316 00:15:52,986 --> 00:15:56,354 was when that Pu'u 'O'o lava made it, 317 00:15:56,356 --> 00:15:58,022 then the eruption scale would change. 318 00:16:01,962 --> 00:16:03,394 NARRATOR: As the Leilani neighborhood 319 00:16:03,396 --> 00:16:05,730 waits to see what will come next, 320 00:16:05,732 --> 00:16:08,433 alarms are sounding at the top of the mountain, 321 00:16:08,435 --> 00:16:11,502 where the summit is rumbling. 322 00:16:11,504 --> 00:16:14,906 Since May 2, the lava here has retreated, 323 00:16:14,908 --> 00:16:18,643 following the Pu'u 'O'o lava into the depths. 324 00:16:18,645 --> 00:16:23,247 It's dropped 500 feet, and is still sinking fast. 325 00:16:23,249 --> 00:16:24,649 Without the lava to support them, 326 00:16:24,651 --> 00:16:27,952 the sides are slowly collapsing, 327 00:16:27,954 --> 00:16:31,522 falling on top of the descending lava 328 00:16:31,524 --> 00:16:35,460 and generating ominous clouds of ash and dust. 329 00:16:36,629 --> 00:16:40,398 Just four miles away lies the small town of Volcano. 330 00:16:40,400 --> 00:16:44,502 Residents Tom Peek and his wife, Catherine Robins, 331 00:16:44,504 --> 00:16:46,871 are preparing for what might be coming. 332 00:16:46,873 --> 00:16:48,006 (tarp rustling) 333 00:16:48,008 --> 00:16:50,508 As soon as the ash starts to fall, 334 00:16:50,510 --> 00:16:52,176 we're tearing this down. That's a good idea. 335 00:16:53,546 --> 00:16:56,080 NARRATOR: They fear not flowing lava, 336 00:16:56,082 --> 00:16:58,750 but a deadly assault from the skies. 337 00:16:58,752 --> 00:17:03,054 As a former National Park ranger, 338 00:17:03,056 --> 00:17:06,591 Tom is a keen student of Kilauea's explosive history. 339 00:17:06,593 --> 00:17:09,193 From all that we understand, 340 00:17:09,195 --> 00:17:11,696 everything is panning out very similar. 341 00:17:11,698 --> 00:17:15,333 There's some differences in timeframe, 342 00:17:15,335 --> 00:17:18,469 but there's a very parallel kind of story developing 343 00:17:18,471 --> 00:17:22,073 as if this will be a 1924 eruption. 344 00:17:23,309 --> 00:17:27,145 NARRATOR: In 1924, the summit of Kilauea exploded, 345 00:17:27,147 --> 00:17:31,516 propelling searing ash miles into the heavens 346 00:17:31,518 --> 00:17:34,852 and showering eight-ton rocks 347 00:17:34,854 --> 00:17:37,321 up to half a mile from the summit. 348 00:17:37,323 --> 00:17:39,323 The explosion was probably triggered 349 00:17:39,325 --> 00:17:41,259 by a build-up of gas. 350 00:17:43,396 --> 00:17:45,196 When the magma level drops, 351 00:17:45,198 --> 00:17:48,132 falling rubble will eventually block the narrow feed pipe 352 00:17:48,134 --> 00:17:50,401 like a cork in a bottle. 353 00:17:50,403 --> 00:17:52,904 If the magma drops below the water table, 354 00:17:52,906 --> 00:17:55,039 steam will form in the gap. 355 00:17:55,041 --> 00:17:56,774 The build-up of pressurized gas 356 00:17:56,776 --> 00:17:59,610 can cause violent explosions, 357 00:17:59,612 --> 00:18:04,315 firing red-hot rock and ash thousands of feet into the sky. 358 00:18:08,354 --> 00:18:10,354 NEAL: Our geophysicists were able to model 359 00:18:10,356 --> 00:18:14,158 at that current rate of draining of the lava lake, 360 00:18:14,160 --> 00:18:17,061 when the level would pass what we believed to be 361 00:18:17,063 --> 00:18:19,764 the level of the water table within the volcano. 362 00:18:19,766 --> 00:18:21,332 So we had projected the middle of May 363 00:18:21,334 --> 00:18:24,569 as the likely window for onset of explosions. 364 00:18:26,139 --> 00:18:27,638 NARRATOR: While residents near the summit 365 00:18:27,640 --> 00:18:30,241 anxiously wait for Kilauea to blow her top, 366 00:18:30,243 --> 00:18:31,442 back down the mountain, 367 00:18:31,444 --> 00:18:35,346 the Leilani neighborhood faces a new threat. 368 00:18:35,348 --> 00:18:37,915 The media broadcast a dire warning. 369 00:18:37,917 --> 00:18:39,550 REPORTER: Gas so toxic 370 00:18:39,552 --> 00:18:42,153 it's killing trees and grass. 371 00:18:42,155 --> 00:18:44,288 The fire crews that are out there 372 00:18:44,290 --> 00:18:46,057 have reported those toxic levels; 373 00:18:46,059 --> 00:18:47,425 it can be fatal. 374 00:18:48,661 --> 00:18:51,295 NARRATOR: Despite the lull in eruptive activity, 375 00:18:51,297 --> 00:18:55,600 the gas is now being detected all around the neighborhood. 376 00:18:55,602 --> 00:18:57,668 Forced to wear protective breathing equipment, 377 00:18:57,670 --> 00:18:58,836 volcanologist Sam Mitchell 378 00:18:58,838 --> 00:19:01,205 has gone in to investigate. 379 00:19:03,476 --> 00:19:05,076 MITCHELL: Only a few days ago, 380 00:19:05,078 --> 00:19:06,878 this was actively erupting lava. 381 00:19:07,881 --> 00:19:09,113 You can really feel the heat coming off 382 00:19:09,115 --> 00:19:11,115 of some of these fissures right here. 383 00:19:11,117 --> 00:19:12,683 It's really something. 384 00:19:12,685 --> 00:19:16,521 NARRATOR: The air is filled with steam, 385 00:19:16,523 --> 00:19:20,391 and invisible toxic gas rises from the cracks. 386 00:19:20,393 --> 00:19:21,626 The giveaway: 387 00:19:21,628 --> 00:19:25,029 yellow mineral deposits around the fissures-- 388 00:19:25,031 --> 00:19:27,131 sulfur. 389 00:19:27,133 --> 00:19:28,232 As we walk along, 390 00:19:28,234 --> 00:19:30,334 you can actually see all the sulfur 391 00:19:30,336 --> 00:19:32,537 that is actually crystallizing out of these gases 392 00:19:32,539 --> 00:19:33,871 in the cracks. 393 00:19:33,873 --> 00:19:37,308 See how intense the color of these crystals are. 394 00:19:37,310 --> 00:19:39,510 Like, it's precipitating out pure sulfur here. 395 00:19:40,613 --> 00:19:42,380 NARRATOR: The particles of sulfur 396 00:19:42,382 --> 00:19:46,884 indicate that the air is filled with sulfur dioxide, 397 00:19:46,886 --> 00:19:51,389 bubbling out from the magma deep below. 398 00:19:51,391 --> 00:19:54,425 In the presence of moisture and sunlight, 399 00:19:54,427 --> 00:19:58,162 the sulfur dioxide forms vog, a volcanic smog 400 00:19:58,164 --> 00:20:02,300 containing tiny droplets of sulfuric acid. 401 00:20:02,302 --> 00:20:05,503 It makes eyes burn, lungs inflame, 402 00:20:05,505 --> 00:20:08,072 and can even corrode metal. 403 00:20:08,074 --> 00:20:11,576 At high levels, it can be deadly. 404 00:20:11,578 --> 00:20:13,744 Wow! This is really... 405 00:20:13,746 --> 00:20:16,781 Really, really outgassing at the moment. 406 00:20:21,888 --> 00:20:24,088 NARRATOR: High levels of sulfur dioxide 407 00:20:24,090 --> 00:20:27,291 continue to pump into the air each day, 408 00:20:27,293 --> 00:20:33,164 a sign that magma is building up just below the surface. 409 00:20:39,539 --> 00:20:41,739 In another part of the neighborhood, 410 00:20:41,741 --> 00:20:44,542 the gas has temporarily dissipated. 411 00:20:44,544 --> 00:20:48,846 Stacy Welch left her house in a hurry two days ago. 412 00:20:50,617 --> 00:20:52,316 The authorities have given her a few hours 413 00:20:52,318 --> 00:20:55,219 to enter the danger area and check on her property. 414 00:20:56,289 --> 00:20:59,490 The vegetation shows the signs 415 00:20:59,492 --> 00:21:01,659 of sulfur poisoning. 416 00:21:01,661 --> 00:21:04,495 (sighing): All my grass is dead. 417 00:21:04,497 --> 00:21:06,797 It's definitely changed color 418 00:21:06,799 --> 00:21:08,266 since I was here two days ago. 419 00:21:08,268 --> 00:21:12,136 Definitely see a difference in the landscape and everything. 420 00:21:12,138 --> 00:21:16,807 NARRATOR: Fortunately, her house is still untouched by lava. 421 00:21:16,809 --> 00:21:18,209 Hey, Mom, it's me. 422 00:21:18,211 --> 00:21:20,678 We're okay, we're still safe. 423 00:21:20,680 --> 00:21:23,047 NARRATOR: But as she makes her inspection, 424 00:21:23,049 --> 00:21:26,817 there are further indications that the eruption is not over. 425 00:21:26,819 --> 00:21:28,352 (booming in distance) 426 00:21:28,354 --> 00:21:31,422 WELCH: Wow, did you hear that? 427 00:21:31,424 --> 00:21:34,191 I don't know where it's at. 428 00:21:34,193 --> 00:21:37,261 Just... scary. 429 00:21:37,263 --> 00:21:38,863 So scary. 430 00:21:38,865 --> 00:21:40,998 NARRATOR: It's time to leave. 431 00:21:41,000 --> 00:21:45,436 Although the fissures here have been quiet for days, 432 00:21:45,438 --> 00:21:48,939 there are signs that the lull is over. 433 00:21:48,941 --> 00:21:50,341 MITCHELL: I can hear these explosions 434 00:21:50,343 --> 00:21:51,909 happening somewhere here on the left. 435 00:21:51,911 --> 00:21:56,580 There's something happening just around the corner here. 436 00:21:56,582 --> 00:21:58,382 You can really see the heat that's coming off 437 00:21:58,384 --> 00:21:59,450 at the end of the road here. 438 00:21:59,452 --> 00:22:01,719 You can see the heat waves, wow. 439 00:22:01,721 --> 00:22:06,023 I think I can see a red glow just over there, on the side. 440 00:22:06,025 --> 00:22:07,425 Something's on fire. 441 00:22:07,427 --> 00:22:09,393 Yeah, the vegetation's caught fire. 442 00:22:09,395 --> 00:22:12,229 So it's likely there's a small breakout of lava. 443 00:22:12,231 --> 00:22:14,398 (crackling) 444 00:22:14,400 --> 00:22:17,501 This just shows that these fissures can reopen. 445 00:22:19,706 --> 00:22:21,072 At this stage, 446 00:22:21,074 --> 00:22:24,041 we should be hesitant of actually getting any closer. 447 00:22:24,043 --> 00:22:25,943 The activity is really, really picking up. 448 00:22:25,945 --> 00:22:29,413 NARRATOR: Streets away, as Stacy retreats from her property, 449 00:22:29,415 --> 00:22:32,416 she encounters a new flow. 450 00:22:32,418 --> 00:22:34,719 WELCH (gasps): Is that lava? 451 00:22:34,721 --> 00:22:36,620 We were here two hours ago 452 00:22:36,622 --> 00:22:41,592 and it was not this advanced, so it is really moving now. 453 00:22:43,596 --> 00:22:46,530 I thought it was taillights when we pulled in. 454 00:22:46,532 --> 00:22:48,566 But that is definitely not taillights. 455 00:22:48,568 --> 00:22:50,868 That is 100% lava. 456 00:22:50,870 --> 00:22:53,437 NARRATOR: This flow is a sign 457 00:22:53,439 --> 00:22:56,807 that the nature of the eruption is changing. 458 00:22:56,809 --> 00:22:59,944 The fountaining lava is hotter and moving faster 459 00:22:59,946 --> 00:23:03,848 than the old lava that erupted a week ago. 460 00:23:03,850 --> 00:23:05,716 This is the fresh lava from Pu'u 'O'o 461 00:23:05,718 --> 00:23:08,352 that's finally reached the surface. 462 00:23:08,354 --> 00:23:11,622 This eruption has just become more dangerous. 463 00:23:11,624 --> 00:23:13,524 (fire crackling) 464 00:23:13,526 --> 00:23:17,094 WELCH: At any time, my house could go. 465 00:23:17,096 --> 00:23:19,296 This is-- this is unstoppable. 466 00:23:19,298 --> 00:23:20,297 This is... 467 00:23:20,299 --> 00:23:22,600 epic. 468 00:23:22,602 --> 00:23:24,368 I'm never gonna get this close again. 469 00:23:24,370 --> 00:23:25,903 I don't think I ever want to be this close again. 470 00:23:25,905 --> 00:23:28,739 And this is scary and we are not safe. 471 00:23:31,244 --> 00:23:33,177 NARRATOR: With lava on the move, 472 00:23:33,179 --> 00:23:34,178 there is just one option: 473 00:23:34,180 --> 00:23:38,015 get out of the way. 474 00:23:38,017 --> 00:23:40,751 It's a reality that's been faced here 475 00:23:40,753 --> 00:23:43,421 since time immemorial. 476 00:23:43,423 --> 00:23:46,957 (Manaiakalani Kalua chanting in Hawaiian) 477 00:23:46,959 --> 00:23:51,095 (chanting) 478 00:23:52,932 --> 00:23:55,466 NARRATOR: Ever since the first people arrived 479 00:23:55,468 --> 00:23:57,034 on these bountiful islands, 480 00:23:57,036 --> 00:23:59,570 a wealth of beliefs and legends has sprung up 481 00:23:59,572 --> 00:24:04,475 to account for these devastating natural disasters. 482 00:24:04,477 --> 00:24:05,476 In Hawaiian culture, 483 00:24:05,478 --> 00:24:08,979 Pele, the goddess of fire, 484 00:24:08,981 --> 00:24:11,115 resides within the volcano. 485 00:24:11,117 --> 00:24:14,351 (chanting continues) 486 00:24:14,353 --> 00:24:16,887 A lot of people have used the term that she's "upset," 487 00:24:16,889 --> 00:24:20,090 so she's taking out houses, and that's why 488 00:24:20,092 --> 00:24:21,826 there's a lot of destruction and devastation. 489 00:24:21,828 --> 00:24:22,993 She's doing what she does. 490 00:24:22,995 --> 00:24:25,162 We're in her space. 491 00:24:25,164 --> 00:24:28,799 If she takes the house, she takes the house. 492 00:24:28,801 --> 00:24:30,835 If she decides to move around the house 493 00:24:30,837 --> 00:24:32,269 and spare the house, 494 00:24:32,271 --> 00:24:35,339 she decides to move around and spare the house. 495 00:24:35,341 --> 00:24:37,241 But there's temporary permanence 496 00:24:37,243 --> 00:24:40,678 to living within the boundaries of Pele's domain. 497 00:24:40,680 --> 00:24:44,582 NARRATOR: Building a home here has always been a gamble. 498 00:24:44,584 --> 00:24:47,952 And sometimes, your luck runs out. 499 00:24:47,954 --> 00:24:52,022 (Kalua chanting) 500 00:24:52,024 --> 00:24:56,193 May 17, two weeks into the eruption. 501 00:24:56,195 --> 00:24:59,630 Just past 4 a.m., cameras on the peak 502 00:24:59,632 --> 00:25:02,032 of Kilauea's big sister Mauna Kea 503 00:25:02,034 --> 00:25:07,104 catch a huge ash cloud bursting from the summit of Kilauea. 504 00:25:07,106 --> 00:25:08,472 It looks like the summit explosion 505 00:25:08,474 --> 00:25:11,609 predicted by the scientists. 506 00:25:11,611 --> 00:25:14,245 News media pick up the story. 507 00:25:14,247 --> 00:25:16,447 Stunning images tonight: 508 00:25:16,449 --> 00:25:18,616 that powerful explosion at the summit of Kilauea 509 00:25:18,618 --> 00:25:21,585 shooting a plume of ash some 30,000 feet into the air. 510 00:25:21,587 --> 00:25:24,588 NARRATOR: It's the first sign 511 00:25:24,590 --> 00:25:26,891 that bigger explosions might be on the way. 512 00:25:26,893 --> 00:25:31,996 But could it get even worse than the 1924 event? 513 00:25:31,998 --> 00:25:34,298 As magma exits the chamber beneath, 514 00:25:34,300 --> 00:25:35,566 heading down the mountain, 515 00:25:35,568 --> 00:25:39,703 the crater above is collapsing inches per day 516 00:25:39,705 --> 00:25:41,305 in a series of earthquakes. 517 00:25:41,307 --> 00:25:47,077 (land and wall shaking) 518 00:25:47,079 --> 00:25:48,679 If the collapse continues, 519 00:25:48,681 --> 00:25:51,482 it could lead to an even bigger threat. 520 00:25:51,484 --> 00:25:55,553 (explosion echoes) 521 00:25:55,555 --> 00:25:58,322 A pyroclastic surge: 522 00:25:58,324 --> 00:26:01,859 a superheated ash cloud of vaporized rock and magma 523 00:26:01,861 --> 00:26:04,128 capable of flowing across the landscape 524 00:26:04,130 --> 00:26:05,796 at hundreds of miles an hour, 525 00:26:05,798 --> 00:26:09,199 obliterating all it touches. 526 00:26:09,201 --> 00:26:10,701 Hundreds of years ago, 527 00:26:10,703 --> 00:26:13,938 a collapse of Kilauea's crater 528 00:26:13,940 --> 00:26:18,275 led to a similar event. 529 00:26:18,277 --> 00:26:21,011 In 1790, there were quite large surges 530 00:26:21,013 --> 00:26:22,680 of this hot gas and ash 531 00:26:22,682 --> 00:26:24,315 that killed quite a few people. 532 00:26:24,317 --> 00:26:27,885 One of the big concerns was, if this thing gets too big, 533 00:26:27,887 --> 00:26:31,555 are we going to go into a pyroclastic phase? 534 00:26:31,557 --> 00:26:34,024 NARRATOR: The local residents 535 00:26:34,026 --> 00:26:36,794 are increasingly concerned. 536 00:26:36,796 --> 00:26:40,431 PEEK: Here's another plume coming up right now. 537 00:26:40,433 --> 00:26:44,368 It's maybe 7,000 feet high, maybe eight, I don't know. 538 00:26:44,370 --> 00:26:47,538 But I certainly did not expect to see 539 00:26:47,540 --> 00:26:50,574 what I've seen pictures of about 1924, 540 00:26:50,576 --> 00:26:52,910 and I'm certainly hoping not to experience 541 00:26:52,912 --> 00:26:56,513 what I'd read about from 1790. 542 00:26:56,515 --> 00:26:59,817 NARRATOR: The collapse is a worrying sign 543 00:26:59,819 --> 00:27:03,220 that events may be escalating. 544 00:27:05,291 --> 00:27:09,827 Could it be linked to violent new activity 545 00:27:09,829 --> 00:27:12,262 now occurring down the mountain? 546 00:27:12,264 --> 00:27:15,666 Around Leilani Estates, the lull is over, 547 00:27:15,668 --> 00:27:19,770 but the focus of eruptive activity has moved east. 548 00:27:19,772 --> 00:27:21,872 Two new fissures have opened. 549 00:27:21,874 --> 00:27:26,710 One of them, fissure 17, is pumping out exploding lava. 550 00:27:26,712 --> 00:27:30,781 (explosion echoes) 551 00:27:30,783 --> 00:27:33,817 Shooting huge chunks, some as heavy as a refrigerator, 552 00:27:33,819 --> 00:27:36,520 hundreds of feet in the air. 553 00:27:36,522 --> 00:27:38,822 These lava bombs are responsible 554 00:27:38,824 --> 00:27:42,192 for the eruption's first casualty. 555 00:27:42,194 --> 00:27:46,163 The media report on a resident 556 00:27:46,165 --> 00:27:47,965 struck by a bowling ball-sized lava bomb 557 00:27:47,967 --> 00:27:50,868 that nearly sheared his leg in half. 558 00:27:50,870 --> 00:27:55,739 The most forceful impact I've ever had in my body 559 00:27:55,741 --> 00:27:57,041 in my life. 560 00:27:57,043 --> 00:28:01,145 NARRATOR: So is this a sign 561 00:28:01,147 --> 00:28:03,213 that a new type of explosive magma 562 00:28:03,215 --> 00:28:05,315 is building up under Kilauea? 563 00:28:05,317 --> 00:28:07,017 ♪ ♪ 564 00:28:07,019 --> 00:28:11,655 Cheryl's lab quickly analyzes fissure 17 lava. 565 00:28:11,657 --> 00:28:13,924 They find it has an unusual consistency. 566 00:28:13,926 --> 00:28:18,095 Most Hawaiian lava is as runny as ketchup. 567 00:28:18,097 --> 00:28:21,665 It rarely holds on to much magmatic gas. 568 00:28:21,667 --> 00:28:24,201 The gas bubbles in Hawaiian magma 569 00:28:24,203 --> 00:28:25,669 can rise freely, 570 00:28:25,671 --> 00:28:27,204 and they just basically, just burst at the surface 571 00:28:27,206 --> 00:28:30,607 and release the gas. 572 00:28:30,609 --> 00:28:32,710 (explosion echoes) 573 00:28:32,712 --> 00:28:37,648 NARRATOR: But fissure 17 lava is rich in silica, 574 00:28:37,650 --> 00:28:39,717 the main ingredient in common sand. 575 00:28:39,719 --> 00:28:41,285 The silica thickens the lava 576 00:28:41,287 --> 00:28:44,321 to the consistency of peanut butter. 577 00:28:44,323 --> 00:28:46,724 The stiffer your magma, the more viscous it is. 578 00:28:46,726 --> 00:28:49,460 So when gas bubbles are trying to escape, 579 00:28:49,462 --> 00:28:50,794 they can't expand very well, 580 00:28:50,796 --> 00:28:52,963 and they tend to build up a lot of pressure 581 00:28:52,965 --> 00:28:54,098 and then explode. 582 00:28:54,100 --> 00:28:57,968 (explosion echoes) 583 00:28:59,071 --> 00:29:01,572 NARRATOR: Most volcanoes around the world 584 00:29:01,574 --> 00:29:03,774 are fed by silica-rich magma, 585 00:29:03,776 --> 00:29:06,376 explaining the prevalence of explosive eruptions. 586 00:29:06,378 --> 00:29:09,613 If magma this thick were to build up 587 00:29:09,615 --> 00:29:11,482 beneath Kilauea's summit, 588 00:29:11,484 --> 00:29:13,984 a major explosion could be in the cards. 589 00:29:13,986 --> 00:29:17,287 But Cheryl's team have found chemical evidence 590 00:29:17,289 --> 00:29:21,225 that the fissure 17 lava is not fresh from the summit at all. 591 00:29:21,227 --> 00:29:23,660 It seems to come from another hidden remnant 592 00:29:23,662 --> 00:29:27,498 of extremely old magma from a previous eruption, 593 00:29:27,500 --> 00:29:30,267 even older than the 1955-type magma 594 00:29:30,269 --> 00:29:34,538 originally encountered under Leilani Estates. 595 00:29:34,540 --> 00:29:37,708 The chemistry was extremely evolved, 596 00:29:37,710 --> 00:29:40,210 meaning that it had been stored longer 597 00:29:40,212 --> 00:29:43,180 than anything we'd ever seen erupt on Kilauea. 598 00:29:43,182 --> 00:29:47,818 (explosion echoes) 599 00:29:47,820 --> 00:29:50,387 NARRATOR: The longer a magma is stored, 600 00:29:50,389 --> 00:29:54,424 chemical changes increase the concentration of silica. 601 00:29:54,426 --> 00:29:56,894 Fissure 17's lava is explosive, 602 00:29:56,896 --> 00:30:00,397 but it's tied to a small, isolated pocket 603 00:30:00,399 --> 00:30:01,832 of thickened magma. 604 00:30:01,834 --> 00:30:04,968 This discovery indicates that the explosive lava 605 00:30:04,970 --> 00:30:07,771 is unrelated to the events at the summit. 606 00:30:07,773 --> 00:30:09,773 And for now, the collapse of the crater 607 00:30:09,775 --> 00:30:13,277 is not great enough to trigger a pyroclastic eruption. 608 00:30:13,279 --> 00:30:15,379 (ground shaking) 609 00:30:15,381 --> 00:30:17,781 But the ground continues to shake, 610 00:30:17,783 --> 00:30:20,284 and the summit is still subsiding 611 00:30:20,286 --> 00:30:23,020 as more and more magma exits the chamber beneath, 612 00:30:23,022 --> 00:30:28,125 heading for the open fissures. 613 00:30:28,127 --> 00:30:30,060 Down the mountain, 614 00:30:30,062 --> 00:30:33,096 the thick silica-rich lava of fissure 17 615 00:30:33,098 --> 00:30:35,899 is starting to congeal. 616 00:30:35,901 --> 00:30:38,202 But as pressure from the summit continues, 617 00:30:38,204 --> 00:30:40,971 forceful new fissure are opening behind it, 618 00:30:40,973 --> 00:30:45,475 generating new flows heading in many directions. 619 00:30:45,477 --> 00:30:47,277 ♪ ♪ 620 00:30:47,279 --> 00:30:49,680 NEAL: Understanding where the lava was going 621 00:30:49,682 --> 00:30:51,281 was absolutely critical 622 00:30:51,283 --> 00:30:53,550 to providing situational awareness 623 00:30:53,552 --> 00:30:54,651 for the civil authorities 624 00:30:54,653 --> 00:30:56,019 and issuing public warnings in time. 625 00:30:56,021 --> 00:30:58,689 With multiple fissures erupting, this was a challenge. 626 00:30:58,691 --> 00:31:01,458 NARRATOR: Luckily, the authorities 627 00:31:01,460 --> 00:31:05,529 can call on some state-of-the-art technology. 628 00:31:05,531 --> 00:31:08,966 We were requested to help participate 629 00:31:08,968 --> 00:31:11,268 by Hawai'i County Civil Defense. 630 00:31:11,270 --> 00:31:13,170 And so we said, "Of course, whatever we can do." 631 00:31:13,172 --> 00:31:15,138 (drone buzzing) 632 00:31:15,140 --> 00:31:19,076 NARRATOR: Ryan Perroy's team from the University of Hawai'i 633 00:31:19,078 --> 00:31:20,544 has been experimenting with drones 634 00:31:20,546 --> 00:31:23,113 to track lava flows. 635 00:31:23,115 --> 00:31:27,317 Now their expertise will prove vital. 636 00:31:27,319 --> 00:31:30,654 ♪ ♪ 637 00:31:30,656 --> 00:31:32,289 By returning repeatedly 638 00:31:32,291 --> 00:31:35,492 to a GPS-determined fixed point above the lava's edge, 639 00:31:35,494 --> 00:31:37,694 the drones accurately plot 640 00:31:37,696 --> 00:31:41,131 precisely how fast a flow is advancing. 641 00:31:41,133 --> 00:31:43,567 And unlike helicopters, 642 00:31:43,569 --> 00:31:45,669 drones can safely operate day and night. 643 00:31:45,671 --> 00:31:47,504 (buzzing) 644 00:31:47,506 --> 00:31:50,073 ♪ ♪ 645 00:31:50,075 --> 00:31:51,875 PERROY: It's critically important 646 00:31:51,877 --> 00:31:53,777 to be able to monitor the flows on a 24-hour basis, 647 00:31:53,779 --> 00:31:56,313 because even if everybody's asleep, you know, 648 00:31:56,315 --> 00:31:57,848 the lava's going to potentially advance. 649 00:31:57,850 --> 00:32:01,718 NARRATOR: Using thermal cameras, they can register 650 00:32:01,720 --> 00:32:05,188 the heat signatures of hidden subterranean cracks, 651 00:32:05,190 --> 00:32:11,495 helping to forewarn which ones may evolve into new fissures. 652 00:32:11,497 --> 00:32:14,564 And they can help determine which parts of a flow 653 00:32:14,566 --> 00:32:18,001 may lead the next advance. 654 00:32:18,003 --> 00:32:21,238 PERROY: We've got areas down here which have cooled off. 655 00:32:21,240 --> 00:32:22,606 These are probably not the places 656 00:32:22,608 --> 00:32:24,541 where you're going to expect to have new breakouts. 657 00:32:24,543 --> 00:32:26,610 You're going to see them here and here. 658 00:32:27,846 --> 00:32:29,780 NARRATOR: Drone predictions become vital 659 00:32:29,782 --> 00:32:32,249 to the emergency services, 660 00:32:32,251 --> 00:32:34,685 who are able to clear everyone 661 00:32:34,687 --> 00:32:40,090 safely out of the paths of the multiple advancing flows. 662 00:32:40,092 --> 00:32:41,224 But though tracking its short-term movements 663 00:32:41,226 --> 00:32:42,993 can be complicated, 664 00:32:42,995 --> 00:32:44,394 if it keeps flowing, 665 00:32:44,396 --> 00:32:49,032 a red-hot lava river will always head downhill. 666 00:32:50,069 --> 00:32:52,402 Over three days, the new flows make their way 667 00:32:52,404 --> 00:32:54,438 down to the ocean. 668 00:32:54,440 --> 00:32:57,574 But even as they arrive, their power wanes. 669 00:32:57,576 --> 00:33:00,077 The pressure of magma coming down the mountain 670 00:33:00,079 --> 00:33:03,013 is now reinvigorating old fissures, 671 00:33:03,015 --> 00:33:06,950 moving the center of activity back to Leilani Estates. 672 00:33:06,952 --> 00:33:09,786 (churning) 673 00:33:09,788 --> 00:33:13,957 Lava is gushing faster than ever before, 674 00:33:13,959 --> 00:33:15,459 and pooling within the hardened banks 675 00:33:15,461 --> 00:33:18,528 created by the earlier flows. 676 00:33:18,530 --> 00:33:21,465 Levels are rising by the hour, 677 00:33:21,467 --> 00:33:22,899 as lava pumps out 678 00:33:22,901 --> 00:33:26,903 at over 40 cubic feet per second. 679 00:33:26,905 --> 00:33:28,872 NEAL: Those rates of eruptive activity, 680 00:33:28,874 --> 00:33:30,040 rates of lava flux, 681 00:33:30,042 --> 00:33:32,609 really had not been seen at Kilauea before. 682 00:33:32,611 --> 00:33:34,878 PERROY: If it was able to sort of overflow those banks, 683 00:33:34,880 --> 00:33:36,146 then all bets are off 684 00:33:36,148 --> 00:33:38,248 in terms of where it's going to cover next. 685 00:33:38,250 --> 00:33:41,618 NARRATOR: Residents who thought they'd escaped the worst 686 00:33:41,620 --> 00:33:43,653 are about to be hit again. 687 00:33:43,655 --> 00:33:46,456 (lava churning) 688 00:33:46,458 --> 00:33:49,459 It was just building up and building up 689 00:33:49,461 --> 00:33:54,197 till surface tension gave 690 00:33:54,199 --> 00:33:55,665 and it spilled over. 691 00:33:55,667 --> 00:34:02,406 (eruption roaring) 692 00:34:02,408 --> 00:34:07,978 MAN: This is insane. 693 00:34:07,980 --> 00:34:10,280 HANSON: Lava's moving, 694 00:34:10,282 --> 00:34:15,452 encroaching at the rate of one property a minute. 695 00:34:15,454 --> 00:34:18,321 Very quickly, it became of a scale and magnitude 696 00:34:18,323 --> 00:34:19,990 greater than what we were able to handle. 697 00:34:19,992 --> 00:34:22,993 ♪ ♪ 698 00:34:22,995 --> 00:34:27,831 NARRATOR: The authorities scramble to warn nearby residents, 699 00:34:27,833 --> 00:34:32,536 while drones keep an eye on the advancing lava. 700 00:34:32,538 --> 00:34:34,037 (drone buzzing) 701 00:34:34,039 --> 00:34:37,941 Watching live drone footage at Civil Defense Headquarters, 702 00:34:37,943 --> 00:34:39,309 Bill Hanson suddenly spots something 703 00:34:39,311 --> 00:34:41,378 in the depths of the forest. 704 00:34:44,249 --> 00:34:45,348 HANSON: The lights were flashing. 705 00:34:45,350 --> 00:34:46,583 And I looked at it, 706 00:34:46,585 --> 00:34:47,918 and I said, "Guys, do you know what he's doing? 707 00:34:47,920 --> 00:34:50,620 He's flashing S.O.S." 708 00:34:50,622 --> 00:34:52,823 NARRATOR: Forced to abandon his car, 709 00:34:52,825 --> 00:34:56,393 a resident has become disoriented, 710 00:34:56,395 --> 00:35:00,797 his cell phone his only link to his rescuers. 711 00:35:00,799 --> 00:35:05,302 A 911 operator patches him in to the Civil Defense team, 712 00:35:05,304 --> 00:35:07,170 who summon the drone to his aid. 713 00:35:07,172 --> 00:35:08,605 HANSON: And so we told him, 714 00:35:08,607 --> 00:35:09,739 "Can you see the drone?" 715 00:35:09,741 --> 00:35:11,108 He goes, "Yes, I can see the drone." 716 00:35:11,110 --> 00:35:14,077 And we said, "Please follow the drone out-- 717 00:35:14,079 --> 00:35:15,879 the drone will lead you to safety." 718 00:35:15,881 --> 00:35:18,482 NARRATOR: Assisted by the flying beacon, 719 00:35:18,484 --> 00:35:21,818 the man is able to find his way out of the forest, 720 00:35:21,820 --> 00:35:24,855 and make contact with the rescue team. 721 00:35:24,857 --> 00:35:26,523 And everybody was, of course, elated 722 00:35:26,525 --> 00:35:29,092 that we were able to work technology 723 00:35:29,094 --> 00:35:31,695 into saving a life. 724 00:35:31,697 --> 00:35:34,097 That was a really special story 725 00:35:34,099 --> 00:35:38,735 that we were proud to be part of. 726 00:35:40,139 --> 00:35:44,141 NARRATOR: The eruption has now entered a new phase. 727 00:35:44,143 --> 00:35:46,910 From this point on, one fissure starts to dominate-- 728 00:35:46,912 --> 00:35:48,378 fissure eight. 729 00:35:48,380 --> 00:35:51,515 Its flow rate is so great 730 00:35:51,517 --> 00:35:54,251 that the spatter forms an immense cone... 731 00:35:54,253 --> 00:35:59,055 (lava churning) 732 00:35:59,057 --> 00:36:00,924 ...as it pumps out 733 00:36:00,926 --> 00:36:03,226 over 3,000 cubic feet of lava per second... 734 00:36:03,228 --> 00:36:09,733 (lava flowing) 735 00:36:09,735 --> 00:36:13,870 ...forming a vast river hundreds of yards across. 736 00:36:13,872 --> 00:36:20,177 ♪ ♪ 737 00:36:20,179 --> 00:36:22,679 PERROY: It is an awe-inspiring thing 738 00:36:22,681 --> 00:36:25,949 to watch these flows and watch them evolve 739 00:36:25,951 --> 00:36:27,384 and change over time, 740 00:36:27,386 --> 00:36:32,989 and to see these immense channels and rivers of lava 741 00:36:32,991 --> 00:36:35,392 just passing underneath you. 742 00:36:35,394 --> 00:36:40,363 It is a very humbling experience. 743 00:36:40,365 --> 00:36:43,533 ♪ ♪ 744 00:36:49,007 --> 00:36:53,677 NARRATOR: The new flow powers forward for miles and miles. 745 00:36:58,750 --> 00:37:01,585 It's now clear the effects of this eruption 746 00:37:01,587 --> 00:37:05,288 will be widespread and long-lasting. 747 00:37:05,290 --> 00:37:09,893 Countless more acres will be poisoned 748 00:37:09,895 --> 00:37:14,264 or buried under a red-hot blanket. 749 00:37:14,266 --> 00:37:17,167 But for the Hawaiian ecosystem, this is not the calamity 750 00:37:17,169 --> 00:37:19,970 that it first appears. 751 00:37:19,972 --> 00:37:22,505 The wave of destruction may ultimately generate 752 00:37:22,507 --> 00:37:25,308 the seeds of life. 753 00:37:30,349 --> 00:37:32,916 Rick Hazlett, from the University of Hawai'i, 754 00:37:32,918 --> 00:37:35,518 is investigating a cave hidden in the rainforest. 755 00:37:37,389 --> 00:37:41,625 A gateway to the Hawaiian underworld, 756 00:37:41,627 --> 00:37:46,596 revealing subterranean secrets about the island's formation. 757 00:37:48,400 --> 00:37:50,500 HAZLETT: To enter one of these caves 758 00:37:50,502 --> 00:37:54,671 is like seeing the inside of an eruption. 759 00:37:54,673 --> 00:37:58,675 ♪ ♪ 760 00:37:58,677 --> 00:38:01,611 This is a lava tube. 761 00:38:09,554 --> 00:38:10,987 NARRATOR: Countless numbers 762 00:38:10,989 --> 00:38:12,956 of these huge subterranean tubes 763 00:38:12,958 --> 00:38:15,592 crisscross Hawai'i. 764 00:38:16,728 --> 00:38:20,530 Some, like this one, can be over 30 miles long. 765 00:38:22,534 --> 00:38:26,102 They are the remains of lava flows 766 00:38:26,104 --> 00:38:28,705 that hardened on the outside, 767 00:38:28,707 --> 00:38:30,273 but stayed liquid on the inside, 768 00:38:30,275 --> 00:38:33,777 continuing to flow for months or years 769 00:38:33,779 --> 00:38:36,579 until they ran out of lava. 770 00:38:36,581 --> 00:38:39,616 HAZLETT: So like a dam or a reservoir draining, 771 00:38:39,618 --> 00:38:43,820 the lava emptied this passageway and exposed the cave 772 00:38:43,822 --> 00:38:46,923 that we can enjoy and explore today. 773 00:38:49,494 --> 00:38:51,461 NARRATOR: You don't see lava tubes 774 00:38:51,463 --> 00:38:53,363 in many places around the world. 775 00:38:53,365 --> 00:38:56,933 Unusually hot lava is needed to maintain tunnels 776 00:38:56,935 --> 00:39:00,804 that can extend such great distances. 777 00:39:00,806 --> 00:39:03,340 (lava churning) 778 00:39:03,342 --> 00:39:06,009 But Hawaiian volcanoes cook up some of the hottest lava 779 00:39:06,011 --> 00:39:08,111 on Earth, 780 00:39:08,113 --> 00:39:13,249 over 200 degrees hotter than most other volcanoes. 781 00:39:13,251 --> 00:39:17,320 So Hawaiian flows can spread the lava 782 00:39:17,322 --> 00:39:19,289 far and wide. 783 00:39:19,291 --> 00:39:20,957 HAZLETT: They're landscape builders. 784 00:39:20,959 --> 00:39:23,727 They're like a metro system delivering passengers 785 00:39:23,729 --> 00:39:25,395 here and there. 786 00:39:25,397 --> 00:39:27,597 In this case, the delivery is molten lava, 787 00:39:27,599 --> 00:39:32,102 and the product is a new landscape, a larger island. 788 00:39:34,639 --> 00:39:39,175 NARRATOR: Lava flows aren't a curse upon Hawai'i. 789 00:39:39,177 --> 00:39:42,045 They are Hawai'i. 790 00:39:42,047 --> 00:39:44,814 HAZLETT: Essentially, 100% of the landscape 791 00:39:44,816 --> 00:39:46,182 that you view in Hawai'i 792 00:39:46,184 --> 00:39:49,686 is made up of lava flows piled one on top of the other 793 00:39:49,688 --> 00:39:52,822 to build these volcanoes in the sea. 794 00:39:52,824 --> 00:39:56,192 NARRATOR: And it turns out 795 00:39:56,194 --> 00:39:59,763 that this hardened lava is rich in nutrient chemicals. 796 00:39:59,765 --> 00:40:02,532 As the lava breaks down, 797 00:40:02,534 --> 00:40:07,771 it produces some of the most fertile soils on the planet. 798 00:40:11,343 --> 00:40:16,279 From the ashes of destruction, tomorrow's forests will be born. 799 00:40:23,054 --> 00:40:26,723 And there's another distinctive feature of Hawai'i's volcanoes-- 800 00:40:26,725 --> 00:40:29,559 their sheer size. 801 00:40:32,464 --> 00:40:35,932 Take away the ocean, and they are revealed to be 802 00:40:35,934 --> 00:40:38,735 the highest mountains on Earth. 803 00:40:38,737 --> 00:40:42,872 At over 30,000 feet, Kilauea's neighbors, 804 00:40:42,874 --> 00:40:44,240 Mauna Kea and Mauna Loa, 805 00:40:44,242 --> 00:40:46,576 put even Everest in the shade, 806 00:40:46,578 --> 00:40:52,482 all built by a powerful and persistent supply of magma. 807 00:40:52,484 --> 00:40:54,484 Hawaiian volcanoes are maybe the most productive volcanoes 808 00:40:54,486 --> 00:40:55,518 on Earth. 809 00:40:55,520 --> 00:40:58,521 They erupt very frequently, 810 00:40:58,523 --> 00:41:01,791 and just keep piling on more and more and more. 811 00:41:01,793 --> 00:41:04,060 NARRATOR: So what is so special about Hawai'i 812 00:41:04,062 --> 00:41:07,096 that it can supply such an abundance 813 00:41:07,098 --> 00:41:12,535 of extra-hot magma to its volcanoes? 814 00:41:14,005 --> 00:41:16,306 Kilauea is situated on the southeast end 815 00:41:16,308 --> 00:41:19,275 of the island chain. 816 00:41:19,277 --> 00:41:23,179 As you move northwest, the volcanoes become less active, 817 00:41:23,181 --> 00:41:26,049 and the lava flows more ancient. 818 00:41:26,051 --> 00:41:29,319 It's a sign that the Hawaiian chain may be formed 819 00:41:29,321 --> 00:41:33,590 by a powerful force from the depths-- a subterranean hotspot. 820 00:41:37,095 --> 00:41:40,830 Hotspots are generated by plumes of hot, softened rock, 821 00:41:40,832 --> 00:41:44,501 rising up from deep in the mantle. 822 00:41:44,503 --> 00:41:47,237 When they contact the Earth's crustal plate, 823 00:41:47,239 --> 00:41:51,074 the magma infiltrates the solid rock. 824 00:41:51,076 --> 00:41:52,175 Over millions of years, 825 00:41:52,177 --> 00:41:55,144 as the plate passes over the hotspot, 826 00:41:55,146 --> 00:41:58,081 a chain of islands is created. 827 00:41:58,083 --> 00:42:00,984 The plume hypothesis can explain 828 00:42:00,986 --> 00:42:04,554 why Hawai'i's lava is so hot and so abundant. 829 00:42:04,556 --> 00:42:08,558 And why these islands grow at such an impressive rate. 830 00:42:08,560 --> 00:42:13,463 In 2018, this growth is on stark display. 831 00:42:13,465 --> 00:42:16,866 In the first week of June, the main flow from fissure eight 832 00:42:16,868 --> 00:42:18,968 advances through residential areas. 833 00:42:18,970 --> 00:42:21,704 Hundreds more islanders are forced to evacuate 834 00:42:21,706 --> 00:42:24,574 as it makes its way to the ocean. 835 00:42:24,576 --> 00:42:28,077 This time, when it hits, 836 00:42:28,079 --> 00:42:30,647 the flow shows no sign of dying down. 837 00:42:30,649 --> 00:42:33,383 ♪ ♪ 838 00:42:33,385 --> 00:42:36,152 Wherever the front of the flow meets the ocean, 839 00:42:36,154 --> 00:42:37,554 there is an explosive reaction. 840 00:42:37,556 --> 00:42:40,857 (explosion echoing) 841 00:42:40,859 --> 00:42:44,193 Sending lava bombs hundreds of feet into the air. 842 00:42:44,195 --> 00:42:48,097 (explosion echoing) 843 00:42:48,099 --> 00:42:51,067 On July 16, a boatload of tourists 844 00:42:51,069 --> 00:42:52,402 get more than they bargained for 845 00:42:52,404 --> 00:42:56,139 when they get too close to an explosive front line. 846 00:42:56,141 --> 00:43:02,612 (people screaming) 847 00:43:02,614 --> 00:43:07,584 NARRATOR: They are lucky to survive relatively unscathed-- 848 00:43:07,586 --> 00:43:10,954 a few nasty burns and one broken leg. 849 00:43:12,023 --> 00:43:14,891 From the violent clash between ocean and lava, 850 00:43:14,893 --> 00:43:19,062 new land is born. 851 00:43:19,064 --> 00:43:21,731 Coastal waters have been pushed away, 852 00:43:21,733 --> 00:43:25,101 replaced by a lava delta with an area equivalent 853 00:43:25,103 --> 00:43:28,037 to nearly 700 football fields. 854 00:43:29,708 --> 00:43:33,776 As long as the volcanoes stay active, 855 00:43:33,778 --> 00:43:38,047 this island will continue to grow. 856 00:43:38,049 --> 00:43:41,317 But while volcanic eruptions are busy building up Hawai'i, 857 00:43:41,319 --> 00:43:47,023 other processes are busy bringing her down. 858 00:43:47,025 --> 00:43:50,526 Her first enemy is the tropical climate. 859 00:43:52,597 --> 00:43:55,331 (thunder claps) 860 00:43:55,333 --> 00:43:56,899 (rain pelting) 861 00:43:58,770 --> 00:44:05,508 ♪ ♪ 862 00:44:05,510 --> 00:44:07,710 Hawai'i is the wettest state in the U.S.A., 863 00:44:07,712 --> 00:44:11,381 drenched by an average 864 00:44:11,383 --> 00:44:14,717 of over five feet of rain each year. 865 00:44:14,719 --> 00:44:18,187 This deluge results from the combination of high mountains 866 00:44:18,189 --> 00:44:21,591 and an enormous ocean. 867 00:44:21,593 --> 00:44:26,863 Moist air coming off the sea hits the land, rising, cooling, 868 00:44:26,865 --> 00:44:29,766 and releasing downpours 869 00:44:29,768 --> 00:44:33,302 that begin a process of quiet destruction. 870 00:44:34,873 --> 00:44:38,141 ♪ ♪ 871 00:44:38,143 --> 00:44:40,677 Volcanic basalt is a porous rock 872 00:44:40,679 --> 00:44:43,012 highly susceptible to the elements. 873 00:44:47,352 --> 00:44:49,485 HAZLETT: Rock such as this, 874 00:44:49,487 --> 00:44:51,087 the basalt that erupts 875 00:44:51,089 --> 00:44:53,456 and builds these volcanoes in Hawai'i, 876 00:44:53,458 --> 00:44:55,558 is especially prone to weathering 877 00:44:55,560 --> 00:44:57,060 in Earth's atmosphere. 878 00:44:57,062 --> 00:44:59,996 Compared to other rock types, like granite, 879 00:44:59,998 --> 00:45:04,267 rocks like this, exposed to moisture 880 00:45:04,269 --> 00:45:06,969 for very long periods of time in this warm climate, 881 00:45:06,971 --> 00:45:09,672 will slowly dissolve. 882 00:45:09,674 --> 00:45:11,941 You have to think of the Hawaiian Islands 883 00:45:11,943 --> 00:45:15,611 as being temporary geographical features. 884 00:45:18,850 --> 00:45:20,783 NARRATOR: The islands are fragile. 885 00:45:20,785 --> 00:45:23,619 Weathering, erosion, and massive landslides 886 00:45:23,621 --> 00:45:27,724 mean they are continuously crumbling away. 887 00:45:27,726 --> 00:45:29,459 But more importantly, 888 00:45:29,461 --> 00:45:31,728 as the islands drift away from the hotspot, 889 00:45:31,730 --> 00:45:34,430 the cooling plate descends, 890 00:45:34,432 --> 00:45:37,066 drawing them slowly beneath the ocean. 891 00:45:37,068 --> 00:45:40,069 It's been happening for millions of years. 892 00:45:43,308 --> 00:45:46,676 To the northwest lies the Emperor Seamount chain, 893 00:45:46,678 --> 00:45:49,278 stretching thousands of miles-- 894 00:45:49,280 --> 00:45:52,315 relics of previous generations of Hawaiian islands, 895 00:45:52,317 --> 00:45:57,019 now submerged shadows of their former glory. 896 00:45:59,324 --> 00:46:04,393 In 2018, another island remnant disappeared beneath the waves, 897 00:46:04,395 --> 00:46:09,766 the last sands of East Island swallowed by the sea. 898 00:46:12,904 --> 00:46:16,205 So is the Hawaiian archipelago doomed to disappear? 899 00:46:18,810 --> 00:46:22,145 There's new activity just to the southeast of the Big Island. 900 00:46:24,549 --> 00:46:27,817 It's attracted SS Nautilus, a research vessel. 901 00:46:27,819 --> 00:46:31,788 From here, oceanographers are guiding a submersible 902 00:46:31,790 --> 00:46:33,790 down into the depths. 903 00:46:33,792 --> 00:46:35,291 DARLENE LIM: We're working down 904 00:46:35,293 --> 00:46:36,859 about a mile underwater. 905 00:46:36,861 --> 00:46:39,328 It's very dark there-- it's perpetually dark there. 906 00:46:39,330 --> 00:46:44,300 NARRATOR: The submersible has reached its target. 907 00:46:44,302 --> 00:46:46,302 It's time to light up the scene. 908 00:46:55,013 --> 00:46:58,481 LIM: The steepness of it is so remarkable... 909 00:46:58,483 --> 00:46:59,882 CHRIS GERMAN: Look how that drops away down the other side. 910 00:46:59,884 --> 00:47:01,617 LIM: It's incredible. 911 00:47:01,619 --> 00:47:03,152 GERMAN: It's brutal. 912 00:47:03,154 --> 00:47:06,956 NARRATOR: The team find what they are looking for-- 913 00:47:06,958 --> 00:47:10,126 a hydrothermal vent. 914 00:47:10,128 --> 00:47:12,261 LIM: What's very exciting 915 00:47:12,263 --> 00:47:14,463 is that right now, it is active, 916 00:47:14,465 --> 00:47:17,767 and there is hot water that's venting from certain regions. 917 00:47:17,769 --> 00:47:23,372 NARRATOR: The water around the vent is close to boiling point. 918 00:47:23,374 --> 00:47:25,875 It's hot because this piece of land 919 00:47:25,877 --> 00:47:28,945 is the summit of Lo'ihi, 920 00:47:28,947 --> 00:47:32,882 an active volcano submerged beneath the ocean, 921 00:47:32,884 --> 00:47:37,053 created by the same geological hotspot 922 00:47:37,055 --> 00:47:39,789 driving the eruptions on the island above. 923 00:47:39,791 --> 00:47:45,094 Lo'ihi is over two miles high, and growing inches per year. 924 00:47:45,096 --> 00:47:49,932 LIM: This is something which will progress on its own time. 925 00:47:49,934 --> 00:47:52,335 We're going to have to wait hundreds of thousands of years, 926 00:47:52,337 --> 00:47:54,804 would be my guess, or at least tens of thousands of years, 927 00:47:54,806 --> 00:47:58,007 before we see anything that'll breach the surface. 928 00:47:58,009 --> 00:48:01,644 NARRATOR: Lo'ihi will likely form the next island 929 00:48:01,646 --> 00:48:04,580 in the Hawaiian archipelago... 930 00:48:06,351 --> 00:48:10,720 ...proof that as old islands sink beneath the sea, 931 00:48:10,722 --> 00:48:14,357 new islands will rise to replace them. 932 00:48:14,359 --> 00:48:16,692 Hawai'i will survive. 933 00:48:24,369 --> 00:48:31,173 It's weeks later, early October, and Leilani Estates is quiet. 934 00:48:31,175 --> 00:48:33,776 The 100-foot cone of fissure eight, 935 00:48:33,778 --> 00:48:35,978 the center of so much activity, 936 00:48:35,980 --> 00:48:38,080 lies dormant. 937 00:48:38,082 --> 00:48:42,351 For over a month, the scientists have detected 938 00:48:42,353 --> 00:48:46,255 little eruptive activity anywhere on the volcano. 939 00:48:46,257 --> 00:48:48,424 FRANK TRUSDELL: There is no molten lava 940 00:48:48,426 --> 00:48:52,061 in this area at the surface. 941 00:48:52,063 --> 00:48:55,865 There is no molten lava anywhere on Kilauea volcano. 942 00:48:55,867 --> 00:49:00,303 For the Leilani eruption, it's over. 943 00:49:00,305 --> 00:49:04,373 NARRATOR: This eruption lasted over three months, 944 00:49:04,375 --> 00:49:07,810 producing enough lava to bury the whole of Manhattan 945 00:49:07,812 --> 00:49:10,880 nearly 30 feet deep. 946 00:49:10,882 --> 00:49:13,649 It covered nearly 14 square miles, 947 00:49:13,651 --> 00:49:18,154 and built 875 acres of new land in the ocean. 948 00:49:18,156 --> 00:49:22,725 ♪ ♪ 949 00:49:24,128 --> 00:49:26,228 At the top of the mountain, 950 00:49:26,230 --> 00:49:29,465 the dreaded summit eruption never materialized. 951 00:49:29,467 --> 00:49:32,068 But the draining of the magma chamber 952 00:49:32,070 --> 00:49:34,937 led to an epic slow-motion collapse. 953 00:49:39,777 --> 00:49:43,179 The crater is now 15 times larger, 954 00:49:43,181 --> 00:49:47,850 and deeper than the Empire State Building is high. 955 00:49:50,355 --> 00:49:53,122 Those who chose to live on the slopes of Kilauea 956 00:49:53,124 --> 00:49:54,757 are counting the cost 957 00:49:54,759 --> 00:49:59,028 of their high-stakes bargain with paradise. 958 00:49:59,030 --> 00:50:03,466 Over 700 properties were swallowed by the lava. 959 00:50:03,468 --> 00:50:08,637 Stacy Welch is one of the lucky ones. 960 00:50:08,639 --> 00:50:11,040 Her house is still standing. 961 00:50:11,042 --> 00:50:12,942 WELCH: I'm still in shock. 962 00:50:12,944 --> 00:50:19,115 It's just the power of nature-- it's unbelievable. 963 00:50:19,117 --> 00:50:21,550 That's incredible to me, 964 00:50:21,552 --> 00:50:25,287 to have something just come and wipe everything out 965 00:50:25,289 --> 00:50:28,557 when there were 700 homes there, and now there's nothing. 966 00:50:28,559 --> 00:50:31,927 There are no words sometimes. 967 00:50:31,929 --> 00:50:35,698 The healing from this is, it's going to be lifelong. 968 00:50:35,700 --> 00:50:38,334 It makes all your other problems look really small 969 00:50:38,336 --> 00:50:39,635 when you're dealing with lava. 970 00:50:39,637 --> 00:50:42,571 I would not have wanted to miss it, 971 00:50:42,573 --> 00:50:44,840 but I don't want it to happen again. 972 00:50:48,546 --> 00:50:51,347 KALUA: You know, we all know 973 00:50:51,349 --> 00:50:52,681 that there's a possibility 974 00:50:52,683 --> 00:50:54,183 that we may not have a house tomorrow. 975 00:50:56,454 --> 00:51:01,757 But if we can live with her, if we do what we need to do 976 00:51:01,759 --> 00:51:04,727 in taking care of our land, 977 00:51:04,729 --> 00:51:07,296 that's the ideal of what I think is being Hawaiian. 978 00:51:07,298 --> 00:51:13,002 ♪ ♪ 979 00:51:13,004 --> 00:51:18,207 NARRATOR: In 2018, Kilauea proved her destructive potential. 980 00:51:18,209 --> 00:51:23,079 But if science tells us anything, she isn't done yet. 981 00:51:23,081 --> 00:51:26,082 Scientists are confident that someday, 982 00:51:26,084 --> 00:51:28,184 in the not-too-distant future, 983 00:51:28,186 --> 00:51:31,687 the lava will return. 984 00:51:31,689 --> 00:51:33,823 NEAL: Even though there may not be lava moving across the surface, 985 00:51:33,825 --> 00:51:36,826 HVO is still on guard and being vigilant 986 00:51:36,828 --> 00:51:37,927 and watching the activity, 987 00:51:37,929 --> 00:51:40,262 looking for changes that might mean 988 00:51:40,264 --> 00:51:43,099 that more dangerous activity is coming. 989 00:51:43,101 --> 00:51:45,034 This is a very active volcano, 990 00:51:45,036 --> 00:51:47,903 and it will erupt again. 991 00:52:13,331 --> 00:52:15,664 To order this "NOVA" program on DVD, 992 00:52:15,666 --> 00:52:20,703 visit ShopPBS or call 1-800-PLAY-PBS. 993 00:52:20,705 --> 00:52:26,175 This program is also available on Amazon Prime Video. 994 00:52:26,177 --> 00:52:28,144 ♪ ♪