1 00:00:00,120 --> 00:00:02,839 Speaker 1: Welcome to Thrilling Threads, the show where we pull on 2 00:00:02,879 --> 00:00:06,719 the most fascinating and sometimes terrifying threads of global knowledge 3 00:00:06,919 --> 00:00:08,080 and unpack them for you. 4 00:00:08,400 --> 00:00:11,519 Speaker 2: Today, we are staring down a timeline that feels frankly, 5 00:00:12,080 --> 00:00:15,320 less like a century long climate projection and more like 6 00:00:15,359 --> 00:00:18,440 an uncomfortably specific deadline. 7 00:00:18,559 --> 00:00:20,519 Speaker 1: Yeah, it really does. We're talking about the year twenty 8 00:00:20,559 --> 00:00:23,600 fifty exactly, and our source material for this deep dive 9 00:00:23,920 --> 00:00:27,199 focuses on a pretty unnerving premise. Why are so many 10 00:00:27,280 --> 00:00:31,399 of the world's largest, most vital coastal cities facing this 11 00:00:32,079 --> 00:00:33,600 existential crisis right now? 12 00:00:33,679 --> 00:00:36,240 Speaker 3: And why twenty fifty? Why that specific date. 13 00:00:36,200 --> 00:00:38,640 Speaker 1: Right We often think about the thread as something external, 14 00:00:38,679 --> 00:00:41,439 you know, rising oceans, melting ice caps, way off in 15 00:00:41,439 --> 00:00:44,560 the distance. But the surreal reality for people in Maggie 16 00:00:44,600 --> 00:00:47,000 these areas today is just so much more immediate. You 17 00:00:47,079 --> 00:00:50,719 wake up, it's a beautiful clear day, no hurricane, no storm, 18 00:00:50,799 --> 00:00:52,039 and the streets are flooded. 19 00:00:52,159 --> 00:00:52,520 Speaker 3: Yeah. 20 00:00:52,600 --> 00:00:54,840 Speaker 1: Our sources put as so simply. They say the ocean 21 00:00:54,920 --> 00:00:56,479 is just pushing its way inland. 22 00:00:56,880 --> 00:00:59,560 Speaker 2: That phrase, I think it just captures the shift perfectly 23 00:00:59,640 --> 00:01:02,920 for Deck. Yes, the warning was always about this gradual 24 00:01:03,079 --> 00:01:05,239 universal sea level rise, something. 25 00:01:05,040 --> 00:01:06,480 Speaker 1: That would happen everywhere. 26 00:01:06,040 --> 00:01:10,640 Speaker 2: Slowly exactly, but now the projections for several major cities 27 00:01:10,680 --> 00:01:15,519 are incredibly localized and specific. The messages if nothing changes, 28 00:01:15,879 --> 00:01:17,719 these places fail by twenty fifty. 29 00:01:18,040 --> 00:01:20,280 Speaker 1: So our mission today is really to unpack that, to 30 00:01:20,280 --> 00:01:23,200 get into the complex physics that the sources reveal. We 31 00:01:23,319 --> 00:01:26,799 have to distinguish between that big global factor, the sea 32 00:01:26,840 --> 00:01:31,400 level rise, and the localized land collapse the subsidence, which is, 33 00:01:31,879 --> 00:01:35,159 and this is the key part, often entirely human made. 34 00:01:35,200 --> 00:01:36,040 Speaker 3: That's the core of it. 35 00:01:36,079 --> 00:01:38,200 Speaker 2: The story isn't just that the water is rising, it's 36 00:01:38,200 --> 00:01:40,840 that the ground at the same time is falling, and 37 00:01:40,879 --> 00:01:43,079 in some cases it's falling much much faster. 38 00:01:43,560 --> 00:01:46,959 Speaker 1: We're basically looking for those surprising insights that explain why 39 00:01:47,000 --> 00:01:51,599 a city built on say, soft river delta mud like 40 00:01:51,760 --> 00:01:54,200 New Orleans face is a totally different but just as 41 00:01:54,319 --> 00:01:57,480 urgent threat as a financial hub sitting on porous sponge 42 00:01:57,640 --> 00:01:59,120 like rock like Miami. 43 00:01:58,920 --> 00:02:01,319 Speaker 2: Or a massive city that literally and I mean literally 44 00:02:01,439 --> 00:02:05,120 durraining itself dry like Jakarta. These local conditions, as you said, 45 00:02:05,200 --> 00:02:07,200 they're the true accelerators of the crisis. 46 00:02:07,480 --> 00:02:10,120 Speaker 1: And this isn't just abstract environmental news. I mean, this 47 00:02:10,199 --> 00:02:13,599 is essential knowledge because we're talking about the foundations of 48 00:02:13,639 --> 00:02:15,599 global infrastructure. 49 00:02:15,199 --> 00:02:19,319 Speaker 2: Massive population centers, trillions of dollars in economic activity all 50 00:02:19,319 --> 00:02:22,120 over the next twenty five years. We're analyzing why some 51 00:02:22,159 --> 00:02:24,960 of the world's biggest cities are already below sea level 52 00:02:24,960 --> 00:02:25,639 today and. 53 00:02:25,639 --> 00:02:28,680 Speaker 1: What happens when the land sinks faster than the sea rises. 54 00:02:29,199 --> 00:02:32,280 Understanding that dual dynamic, that's the key to the twenty 55 00:02:32,319 --> 00:02:33,039 fifty line. 56 00:02:33,120 --> 00:02:36,080 Speaker 2: Okay, So to start, we have to establish the primary 57 00:02:36,159 --> 00:02:41,039 factor that is catastrophically amplifying the global sea level threat 58 00:02:41,159 --> 00:02:42,840 for dozens. 59 00:02:42,400 --> 00:02:44,199 Speaker 1: Of major cities, especially in Asia right. 60 00:02:44,159 --> 00:02:47,240 Speaker 2: Especially across Asia. The thing is, for many of them, 61 00:02:47,280 --> 00:02:49,439 it is not the rising ocean that is their biggest 62 00:02:49,479 --> 00:02:50,159 enemy right now. 63 00:02:50,199 --> 00:02:51,199 Speaker 1: It's the ground itself. 64 00:02:51,240 --> 00:02:55,360 Speaker 2: It's the rapid, anthropogenic, so human caused collapse of the 65 00:02:55,360 --> 00:02:58,719 ground beneath them. In several documented cases, the sources make 66 00:02:58,759 --> 00:03:01,800 it crystal clear. The land is sinking faster than the 67 00:03:01,840 --> 00:03:02,719 ocean is rising. 68 00:03:02,919 --> 00:03:05,520 Speaker 1: That's a true dual calamity. The sea is coming up 69 00:03:05,800 --> 00:03:09,560 and the city is simultaneously pulling itself down. And nothing 70 00:03:09,680 --> 00:03:14,599 illustrates this better than Jakarta, the capital of Indonesia. When 71 00:03:14,639 --> 00:03:17,919 I read the figures on Jakarta, I mean I was 72 00:03:18,000 --> 00:03:20,800 genuinely shocked by how immediate the problem is. It's not 73 00:03:20,879 --> 00:03:24,240 a projection, No, this is measured data. It's showing the 74 00:03:24,280 --> 00:03:28,039 ground in some neighborhoods is dropping by more than ten 75 00:03:28,120 --> 00:03:31,120 inches per year annually, annually. I mean, can you just 76 00:03:31,159 --> 00:03:34,360 picture that a foot of land, a foot of concrete 77 00:03:34,680 --> 00:03:38,439 just sinking every single year. It's almost unbelievable rate of 78 00:03:38,520 --> 00:03:39,120 land loss. 79 00:03:39,439 --> 00:03:42,800 Speaker 2: It is an astronomical rate. And the mechanism behind it 80 00:03:42,879 --> 00:03:45,919 is maybe the most sobering part of this whole story, because, 81 00:03:45,960 --> 00:03:48,319 like we said, it's completely self inflicted, a side. 82 00:03:48,159 --> 00:03:49,520 Speaker 1: Effect of failed infrastructure. 83 00:03:49,680 --> 00:03:52,960 Speaker 2: Exactly. You have to understand a little bit about aquafer mechanics. 84 00:03:53,000 --> 00:03:58,199 So Jakarta sits on this massive, deep basin of soft alluvial. 85 00:03:57,680 --> 00:03:59,719 Speaker 3: Soil basically river sediment, river sediment. 86 00:03:59,800 --> 00:04:04,039 Speaker 2: Yeah, and underneath that soil are these vast aquifers, underground 87 00:04:04,120 --> 00:04:07,039 reservoirs of water trapped in the rock and sediment. 88 00:04:07,400 --> 00:04:09,879 Speaker 1: So the water is essentially holding up the ground above it. 89 00:04:09,879 --> 00:04:11,199 It's like a structural support. 90 00:04:11,479 --> 00:04:12,919 Speaker 3: It's the structural support. 91 00:04:13,120 --> 00:04:16,560 Speaker 2: But for decades, because of this massive population boom and 92 00:04:16,600 --> 00:04:20,920 a public water system that was unreliable, too expensive, or 93 00:04:21,040 --> 00:04:22,759 just didn't exist in large parts. 94 00:04:22,600 --> 00:04:23,079 Speaker 3: Of the city. 95 00:04:23,120 --> 00:04:24,319 Speaker 1: People had to find their own water. 96 00:04:24,439 --> 00:04:29,120 Speaker 2: They did, residents and businesses, they drilled their own private wells, 97 00:04:29,759 --> 00:04:32,920 millions of them, and they pulled that water out from 98 00:04:32,959 --> 00:04:35,920 those deep aquifers. And when you pull the water out, 99 00:04:36,079 --> 00:04:38,959 the pressure that held the grains of sediment apart just 100 00:04:39,120 --> 00:04:42,519 dissipates the weight of the city, all the buildings and 101 00:04:42,560 --> 00:04:46,839 the concrete. It presses down, compacting and crushing those soft 102 00:04:46,920 --> 00:04:47,720 clay layers. 103 00:04:47,800 --> 00:04:50,399 Speaker 1: It's like squeezing the water out of a massive sponge. 104 00:04:50,560 --> 00:04:54,079 That's the perfect analogy it is. And that compaction process, 105 00:04:54,439 --> 00:04:59,240 over decades, repeated millions of times, resulted in the land 106 00:04:59,399 --> 00:05:01,079 literally lapsing into the void. 107 00:05:01,199 --> 00:05:03,600 Speaker 2: And that explains the ten inches per year. It is 108 00:05:03,639 --> 00:05:06,480 a geological time bomb that was triggered by a failure 109 00:05:06,519 --> 00:05:07,639 of public works. 110 00:05:07,399 --> 00:05:09,879 Speaker 1: And the consequence is just staggering. I mean, the sources 111 00:05:09,879 --> 00:05:12,160 point out that forty percent of Jakarta is already below 112 00:05:12,160 --> 00:05:16,839 sea level. Right They've built and rebuilt flood walls taller, stronger, 113 00:05:17,480 --> 00:05:20,560 but the ground underneath the wall just keeps dropping. The 114 00:05:20,600 --> 00:05:22,040 ocean just finds a way. 115 00:05:21,839 --> 00:05:24,240 Speaker 2: In you can see this grim history laid out in 116 00:05:24,279 --> 00:05:26,759 the data. The two thousand and seven flooding. 117 00:05:26,519 --> 00:05:28,639 Speaker 1: Four hundred thousand people displaced. 118 00:05:28,839 --> 00:05:32,360 Speaker 2: Then in twenty thirteen, floodwaters reached the presidential palace. 119 00:05:32,519 --> 00:05:35,279 Speaker 3: I mean, that's not some coastal district. That's a national 120 00:05:35,279 --> 00:05:36,199 security issue. 121 00:05:36,240 --> 00:05:39,439 Speaker 1: And then dozens killed in one of the worst floods 122 00:05:39,439 --> 00:05:42,120 in twenty twenty. I mean, it seems fair to say 123 00:05:42,160 --> 00:05:45,360 the government's failure to provide reliable pipe water is what 124 00:05:45,519 --> 00:05:47,800 accelerated this to the point of no return. 125 00:05:48,000 --> 00:05:50,720 Speaker 2: I think the sources absolutely support that conclusion. It's a 126 00:05:50,759 --> 00:05:53,680 tragedy rooted in a socioeconomic problem that turned into a 127 00:05:53,720 --> 00:05:55,240 geological crisis, and. 128 00:05:55,160 --> 00:05:58,600 Speaker 1: That crisis ultimately led to what is I mean, it's 129 00:05:58,720 --> 00:06:01,959 arguably the most dramatic urban response to this kind of 130 00:06:02,040 --> 00:06:03,199 threat in modern history. 131 00:06:03,279 --> 00:06:03,920 Speaker 3: It really is. 132 00:06:04,079 --> 00:06:06,839 Speaker 2: The Indonesian government publicly acknowledged that parts of the city 133 00:06:06,879 --> 00:06:08,920 will become permanently uninhabitable. 134 00:06:08,959 --> 00:06:10,000 Speaker 1: They just admitted defeat. 135 00:06:10,240 --> 00:06:13,519 Speaker 2: They did, and that's why they announced the plan to 136 00:06:13,519 --> 00:06:17,279 move the national capital entirely. They're relocating the heart of 137 00:06:17,279 --> 00:06:20,279 the nation to a brand new city called New Santara 138 00:06:20,759 --> 00:06:22,040 on the island of Borneo. 139 00:06:22,680 --> 00:06:24,519 Speaker 1: Just think about that for a second. That is an 140 00:06:24,600 --> 00:06:30,199 unprecedented admission of vulnerability, a government choosing to spend what 141 00:06:30,399 --> 00:06:34,759 potentially thirty five billion dollars a massive sum, to physically 142 00:06:34,839 --> 00:06:37,959 move the seat of power the historical cultural political center 143 00:06:38,000 --> 00:06:41,120 of the country, rather than fight a battle they know 144 00:06:41,240 --> 00:06:43,600 they cannot win. By twenty fifty. That just sets the 145 00:06:43,639 --> 00:06:45,639 stage for every other city we're going to talk about. 146 00:06:45,800 --> 00:06:46,439 Speaker 3: It really does. 147 00:06:46,720 --> 00:06:48,959 Speaker 2: So let's connect that case to others where the soft 148 00:06:49,000 --> 00:06:51,399 soil plays a role, but maybe the dynamics are a 149 00:06:51,399 --> 00:06:51,920 bit different. 150 00:06:52,079 --> 00:06:54,480 Speaker 3: Let's look at Bangkok and Shanghai, Okay. 151 00:06:54,199 --> 00:06:57,160 Speaker 1: So Bangkok it has a similar profile to Jakarta, at 152 00:06:57,240 --> 00:06:59,959 least in the early stages, though maybe not quite as extreme. 153 00:07:00,720 --> 00:07:04,279 It also sits on incredibly soft clay soil sometimes called 154 00:07:04,319 --> 00:07:08,000 marine clay, and it's sinking for that same combination of reasons. 155 00:07:08,480 --> 00:07:11,279 Historic groundwater extraction, though that is regulated now. 156 00:07:11,120 --> 00:07:14,120 Speaker 2: And the sheer weight of its buildings, the non stop construction. 157 00:07:14,079 --> 00:07:18,639 Speaker 1: Exactly Unlike Jakarta, Bangkok did try to implement pretty stringent 158 00:07:18,680 --> 00:07:22,560 groundwater regulations and they have slowed the rate of subsidence 159 00:07:22,639 --> 00:07:23,120 a lot. 160 00:07:23,000 --> 00:07:24,879 Speaker 2: Which is a success story in its own way. 161 00:07:25,120 --> 00:07:27,879 Speaker 1: It is, but the pressure is still immense because the 162 00:07:27,879 --> 00:07:32,959 city's growth just continues, and the construction deep foundations, basement parking, 163 00:07:33,079 --> 00:07:36,920 all of that adds this colossal weight to that yielding soil, and. 164 00:07:36,879 --> 00:07:40,040 Speaker 2: The city is just so exposed geographically incredibly. 165 00:07:40,040 --> 00:07:42,240 Speaker 1: The sources note that parts of the city are already 166 00:07:42,319 --> 00:07:45,120 less than three feet above sea level. This is not 167 00:07:45,160 --> 00:07:47,839 a city that needs a hurricane to cause a catastrophic problem. 168 00:07:47,920 --> 00:07:49,399 Speaker 3: No, it's just a high tide. 169 00:07:49,160 --> 00:07:51,720 Speaker 1: Just a slightly higher than average high tide, especially during 170 00:07:51,720 --> 00:07:55,600 monsoon season. The stark warning is that by twenty fifty, 171 00:07:56,040 --> 00:07:59,639 tidal flooding is going to become routine, even without major storms. 172 00:08:00,160 --> 00:08:03,560 That makes huge parts of the city just well unusable 173 00:08:03,600 --> 00:08:04,560 for days at a time. 174 00:08:04,720 --> 00:08:07,639 Speaker 2: I'm thinking about the catastrophic floods back in twenty eleven 175 00:08:07,800 --> 00:08:11,040 that shut down global supply chains. That was driven by rainfall, 176 00:08:11,120 --> 00:08:14,120 but it exposed that fundamental vulnerability it did so. 177 00:08:14,439 --> 00:08:15,439 Speaker 3: When we contrast this. 178 00:08:15,439 --> 00:08:19,160 Speaker 2: With Shanghai, we see a city that, because of really 179 00:08:19,199 --> 00:08:23,240 intense and early regulation starting decades ago, has managed to 180 00:08:23,319 --> 00:08:25,680 slow its subsidence dramatically from. 181 00:08:25,480 --> 00:08:28,000 Speaker 1: Fee per decade to millimeters per year. 182 00:08:27,879 --> 00:08:31,160 Speaker 2: Which shows what's possible with that kind of centralized action. 183 00:08:31,959 --> 00:08:36,600 But Shanghai's sheer scale magnifies any remaining vulnerability. It's sitting 184 00:08:36,600 --> 00:08:39,639 on soft sediment near the Yangsee River delta, with. 185 00:08:39,559 --> 00:08:41,320 Speaker 1: Over twenty five million people. 186 00:08:41,440 --> 00:08:45,559 Speaker 2: Twenty five million people and just colossal infrastructure right there 187 00:08:45,559 --> 00:08:46,360 on the coast. 188 00:08:46,519 --> 00:08:49,960 Speaker 1: So for Shanghai, the threat isn't so much constant sinking anymore. 189 00:08:50,240 --> 00:08:54,639 It's more about threat amplification during extreme weather like typhoons exactly. 190 00:08:54,759 --> 00:08:57,639 Speaker 2: The storm surges from typhoons are already severe and getting 191 00:08:57,639 --> 00:09:00,120 more intense. When you combine that with even a small 192 00:09:00,120 --> 00:09:04,600 increase in overall water levels, the consequences are disproportionately enormous. 193 00:09:04,679 --> 00:09:07,559 Speaker 1: The city has invested heavily in defenses though, yeah, massive 194 00:09:07,639 --> 00:09:09,879 coastal dykes floodgates they have. 195 00:09:10,279 --> 00:09:13,480 Speaker 2: But the sources caution that the soft foundation, combined with 196 00:09:13,519 --> 00:09:16,600 that sheer mass of humanity and steel, all sitting right 197 00:09:16,639 --> 00:09:19,799 on the coast facing the Pacific, it means the safety 198 00:09:19,840 --> 00:09:21,440 margin is continuously shrinking. 199 00:09:21,679 --> 00:09:25,399 Speaker 1: So, even with the regulations, that underlying soil of vulnerability 200 00:09:25,480 --> 00:09:28,720 means that when a big typhoon hits, the city is 201 00:09:28,799 --> 00:09:32,240 just much more susceptible to catastrophic damage than a city 202 00:09:32,279 --> 00:09:33,960 built on say, bedrock. 203 00:09:34,240 --> 00:09:36,919 Speaker 2: The battle is constant, even if they've won that first 204 00:09:36,919 --> 00:09:38,360 big fight against subsidence. 205 00:09:38,879 --> 00:09:41,639 Speaker 1: That transition brings us directly to our next big point. 206 00:09:42,399 --> 00:09:45,159 We need to shift the discussion to cities where geography 207 00:09:45,360 --> 00:09:49,039 doesn't just make defenses difficult, it dictates the terms. It 208 00:09:49,080 --> 00:09:53,519 renders standard flood defenses like a simple sea wall, almost useless. 209 00:09:53,639 --> 00:09:55,320 Speaker 2: And this is where we have to talk about Miami. 210 00:09:55,480 --> 00:09:59,639 Speaker 1: Miami its threat profile is completely different from Jakarta's. 211 00:09:59,200 --> 00:10:02,799 Speaker 2: Completely Jakarta is sinking because it's draining its water table. 212 00:10:03,159 --> 00:10:05,360 Miami is in trouble because it sits on something called 213 00:10:05,440 --> 00:10:08,919 Kars topography, specifically porous limestone. 214 00:10:09,000 --> 00:10:10,960 Speaker 1: Okay, let's really unpack that, because this is where the 215 00:10:10,960 --> 00:10:14,799 physics gets so interesting. Kar's topography means the bedrock is 216 00:10:14,840 --> 00:10:17,240 basically riddled with holes and cracks, right like. 217 00:10:17,200 --> 00:10:21,480 Speaker 2: A sponge exactly, The limestone bedrock acts less like a 218 00:10:21,559 --> 00:10:26,240 solid foundation and more like a colossal, rigid sponge or 219 00:10:26,320 --> 00:10:29,879 Swiss cheese. Most coastal cities fight the ocean with a 220 00:10:29,960 --> 00:10:32,039 vertical barrier, a concrete. 221 00:10:31,679 --> 00:10:33,080 Speaker 1: Wall to keep the water out. 222 00:10:33,159 --> 00:10:35,440 Speaker 2: To keep the water out, Miami can't rely on that 223 00:10:35,679 --> 00:10:39,000 because the ocean water moves through the ground itself. Beneath 224 00:10:39,039 --> 00:10:42,559 the wall around the wall via that porous limestone. It's 225 00:10:42,600 --> 00:10:45,480 a hydraulic connection that a wall simply cannot break. 226 00:10:45,759 --> 00:10:48,559 Speaker 1: And I find that mechanism so insidious because it just 227 00:10:48,600 --> 00:10:52,720 bypasses all our traditional defenses. It's the exact reason for 228 00:10:52,840 --> 00:10:56,600 that phenomenon they call sunny day flooding. You can build 229 00:10:56,639 --> 00:10:58,960 the tallest sea wall you can imagine, but on a 230 00:10:59,080 --> 00:11:01,600 high tide, the ocean level is higher than the city's 231 00:11:01,639 --> 00:11:04,159 drainage level, so the water doesn't wait for a storm. 232 00:11:04,200 --> 00:11:07,120 Speaker 2: It just pushes up up through the storm drains, through 233 00:11:07,120 --> 00:11:09,879 cracks in the sidewalks, right through the foundations of low 234 00:11:09,960 --> 00:11:13,279 lying buildings. The city floods on a clear day. It's 235 00:11:13,399 --> 00:11:16,240 geology literally vetoing human engineering. 236 00:11:16,279 --> 00:11:18,159 Speaker 1: There must be a constant maintenance nightmare too. 237 00:11:18,440 --> 00:11:21,519 Speaker 2: It is because the water pushing up isn't just fresh water, 238 00:11:21,600 --> 00:11:26,320 it's saltwater. So you get chronic saltwater intrusion, which contaminates. 239 00:11:25,679 --> 00:11:27,679 Speaker 1: The fresh groundwater that people rely on. 240 00:11:27,720 --> 00:11:32,080 Speaker 2: And it rapidly corrodes the subterranean infrastructure, pipes, electrical conduits, 241 00:11:32,159 --> 00:11:33,039 road foundations. 242 00:11:33,440 --> 00:11:35,039 Speaker 3: It eats them away from the inside out. 243 00:11:35,159 --> 00:11:38,159 Speaker 1: And the data just confirms this is getting worse NOAA 244 00:11:38,320 --> 00:11:41,320 data shows sea levels in South Florida have risen over 245 00:11:41,480 --> 00:11:45,600 eight inches since nineteen fifty, and that's accelerating. Projections are 246 00:11:45,639 --> 00:11:48,000 for another ten to seventeen inches by twenty fifty. 247 00:11:48,080 --> 00:11:51,120 Speaker 2: And you might hear that and think, seventeen inches and 248 00:11:51,159 --> 00:11:52,360 twenty five years, we. 249 00:11:52,320 --> 00:11:54,279 Speaker 1: Can manage that, but not in Miami. 250 00:11:54,360 --> 00:11:58,039 Speaker 2: Not in Miami's geological context, those seventeen inches are catastrophic. 251 00:11:58,240 --> 00:12:00,879 The sources note that even a a few inches makes 252 00:12:00,919 --> 00:12:02,080 neighborhoods unlivable. 253 00:12:02,240 --> 00:12:05,000 Speaker 1: Why just because it increases the frequency that's sunny day 254 00:12:05,039 --> 00:12:06,360 flooding exponentially. 255 00:12:06,480 --> 00:12:09,159 Speaker 2: It shifts the high tide mark just enough to make 256 00:12:09,240 --> 00:12:12,240 what used to be a rare nuisance a chronic, regular 257 00:12:12,279 --> 00:12:14,159 intrusion that never fully drains away. 258 00:12:14,320 --> 00:12:16,360 Speaker 1: So by twenty fifty, we're looking at large parts of 259 00:12:16,399 --> 00:12:20,279 Miami Beach other low lying areas just experiencing chronic flooding, 260 00:12:20,600 --> 00:12:22,559 not from storms, but from the daily tides. 261 00:12:22,919 --> 00:12:26,840 Speaker 2: They're deploying massive pumps, they're raising roads, but those pumps 262 00:12:26,919 --> 00:12:30,080 are fighting a rising water table that is constantly connected 263 00:12:30,120 --> 00:12:34,600 to the ocean beneath the bedrock. It's a relentless structural challenge. 264 00:12:34,639 --> 00:12:37,240 Speaker 1: It really is the difference between trying to keep water 265 00:12:37,639 --> 00:12:40,200 out of a sealed barrel and trying to keep it 266 00:12:40,200 --> 00:12:41,840 out of a basket made of stone. 267 00:12:41,759 --> 00:12:42,919 Speaker 3: A perfect way to put it. So. 268 00:12:43,159 --> 00:12:47,080 Speaker 2: If Miami is fighting porous rock, let's look at New Orleans, 269 00:12:47,360 --> 00:12:51,840 which is fighting an equally difficult but geologically different battle 270 00:12:51,840 --> 00:12:53,720 against soft delta sediment. 271 00:12:54,080 --> 00:12:57,440 Speaker 1: New Orleans is the definition of a survival machine. It's 272 00:12:57,440 --> 00:13:01,279 famous for its whole ecosystem of levees, pumps, flood walls. 273 00:13:01,879 --> 00:13:04,519 Without them, much of the city would immediately. 274 00:13:04,039 --> 00:13:07,159 Speaker 2: Flood because it sits almost entirely below sea level. 275 00:13:07,279 --> 00:13:12,120 Speaker 1: Right It's built on delta sediment silt, sand clay deposited 276 00:13:12,120 --> 00:13:15,480 by the Mississippi River over millennia, and that sediment naturally 277 00:13:15,480 --> 00:13:19,000 compacts over time. The land is inherently designed to sink. 278 00:13:19,320 --> 00:13:21,759 Speaker 2: But here's the double edged sword of human intervention. The 279 00:13:21,840 --> 00:13:24,600 Mississippi River used to flood regularly, and when it did, 280 00:13:24,720 --> 00:13:27,240 it would deposit fresh sediment across the delta. 281 00:13:27,440 --> 00:13:28,600 Speaker 1: It was rebuilding the land. 282 00:13:28,840 --> 00:13:32,600 Speaker 2: It was a dynamic, sustainable cycle. The river built the land, 283 00:13:32,639 --> 00:13:35,120 and the land would slowly sink and the river would 284 00:13:35,120 --> 00:13:35,879 build it up again. 285 00:13:36,039 --> 00:13:38,200 Speaker 1: And for decades we've stopped that from happening. 286 00:13:38,279 --> 00:13:38,879 Speaker 3: Precisely. 287 00:13:39,000 --> 00:13:43,200 Speaker 2: Decades of intensive river control, These massive levees built to 288 00:13:43,200 --> 00:13:47,559 prevent flooding and promote shipping, have prevented that fresh sediment 289 00:13:47,639 --> 00:13:51,320 from reaching the delta. The ground continues to compact, but 290 00:13:51,440 --> 00:13:52,960 nothing is there to rebuild it. 291 00:13:53,240 --> 00:13:54,720 Speaker 1: The land is being starved. 292 00:13:54,840 --> 00:13:55,679 Speaker 3: It's being starved. 293 00:13:55,720 --> 00:13:59,840 Speaker 2: It's a compound failure of geology and our own infrastructure choices. 294 00:14:00,080 --> 00:14:02,159 Speaker 1: So if the river is supposed to rebuild the delta, 295 00:14:02,200 --> 00:14:04,559 why don't we just dredge the sediment that builds up 296 00:14:04,600 --> 00:14:07,200 further north and I don't know, pipe it back down 297 00:14:07,240 --> 00:14:11,120 into the wetlands. That seems like a logical engineering fix. 298 00:14:10,919 --> 00:14:13,519 Speaker 2: And that's a critical question. Engineers have been working on 299 00:14:13,559 --> 00:14:17,000 that for decades. They are attempting that through these massive, 300 00:14:17,120 --> 00:14:19,759 multi billion dollar sediment diversion projects. 301 00:14:19,840 --> 00:14:21,360 Speaker 1: But the scale is the issue. 302 00:14:21,480 --> 00:14:24,679 Speaker 2: The scale is immense. The amount of sediment needed to 303 00:14:24,720 --> 00:14:28,240 restore thousands of square miles of disappearing wetlands and counteract 304 00:14:28,279 --> 00:14:32,159 the sinking is just enormous. Plus diverting it requires making 305 00:14:32,200 --> 00:14:35,200 deliberate cuts in the levee system, which carries its own risks. 306 00:14:35,320 --> 00:14:36,679 It's not a quick fix. 307 00:14:36,559 --> 00:14:39,159 Speaker 1: And we all remember what happened when those defenses failed 308 00:14:39,559 --> 00:14:44,039 during Hurricane Katrina in two thousand and five that was catastrophic. 309 00:14:43,559 --> 00:14:47,480 Speaker 2: Eighty percent of the city flooded. Since then, billions have 310 00:14:47,559 --> 00:14:50,759 been spent on upgrades, creating one of the most sophisticated 311 00:14:50,799 --> 00:14:52,120 defense systems in the world. 312 00:14:52,240 --> 00:14:54,120 Speaker 1: But the challenges just keep stacking up. 313 00:14:54,279 --> 00:14:54,679 Speaker 3: They do. 314 00:14:55,000 --> 00:14:57,080 Speaker 2: On top of the compaction, sea levels in the Gulf 315 00:14:57,120 --> 00:15:00,919 of Mexico are rising faster than the global average, and critically, 316 00:15:01,120 --> 00:15:05,360 those coastal wetlands, the natural storm buffers, they're disappearing at 317 00:15:05,399 --> 00:15:06,519 an alarming. 318 00:15:06,120 --> 00:15:09,000 Speaker 1: Rate, which exposes the city even more it does. 319 00:15:09,559 --> 00:15:13,440 Speaker 2: The projection for twenty fifty is sobering. Without constant upgrades, 320 00:15:13,480 --> 00:15:16,759 which require continuous funding and political will, parts of New 321 00:15:16,840 --> 00:15:21,000 Orleans will face chronic flooding even without major hurricanes. The 322 00:15:21,039 --> 00:15:25,000 city survival is entirely dependent on technology remaining operational two 323 00:15:25,120 --> 00:15:25,960 hundred and four seven. 324 00:15:26,200 --> 00:15:31,159 Speaker 1: It's a heroic but just exhausting race against geology, the sea, 325 00:15:31,679 --> 00:15:32,679 and your own budget. 326 00:15:32,879 --> 00:15:33,519 Speaker 3: It really is. 327 00:15:33,840 --> 00:15:36,399 Speaker 1: It's one thing to see these newer cities built on 328 00:15:36,559 --> 00:15:40,759 soft clay struggle with modern growth. It's another thing, entirely 329 00:15:40,840 --> 00:15:44,960 to see ancient cities. Metropolis is built to last for millennia, 330 00:15:45,399 --> 00:15:48,399 now succumbing to this rapid modern environmental change. 331 00:15:48,519 --> 00:15:51,440 Speaker 2: Yeah, we're talking about places where adaptation has worked for 332 00:15:51,600 --> 00:15:54,879 a thousand years, but that historical limit has been reached. 333 00:15:55,080 --> 00:15:59,480 Speaker 1: Yeah, and Venice is the quintessential, just heartbreaking example of that. 334 00:15:59,519 --> 00:16:00,200 Speaker 3: Absolutely. 335 00:16:00,279 --> 00:16:02,120 Speaker 2: It was founded over a thousand years ago on a 336 00:16:02,159 --> 00:16:05,679 shallow lagoon, famously built on millions of wooden piles driven 337 00:16:05,720 --> 00:16:08,320 into the sediment, and for most of its history it 338 00:16:08,399 --> 00:16:11,919 survived through remarkable ingenuity and adaptation to the rhythm. 339 00:16:11,759 --> 00:16:12,399 Speaker 3: Of the tides. 340 00:16:12,639 --> 00:16:15,399 Speaker 1: But that rhythm, that timeline, it has accelerated past the 341 00:16:15,399 --> 00:16:19,039 point of sustainability. The city floods during these high tide events, 342 00:16:19,039 --> 00:16:24,039 called aqua alta. Historically, these were rare, spectacular occurrences. 343 00:16:23,600 --> 00:16:26,360 Speaker 2: Part of the city's unique character. The sources remind us 344 00:16:26,399 --> 00:16:29,159 that the massive nineteen sixty six flood was considered a 345 00:16:29,200 --> 00:16:32,879 once in a century thing. Now similar floods happen multiple 346 00:16:32,879 --> 00:16:35,679 times in a decade. The character of the city is 347 00:16:35,759 --> 00:16:38,480 changing from one of romance to one of chronic crisis. 348 00:16:38,799 --> 00:16:43,720 Speaker 1: That twenty nineteen event was particularly devastating. Water levels reached 349 00:16:43,759 --> 00:16:47,000 nearly six feet above normal, flooding over eighty percent of 350 00:16:47,000 --> 00:16:49,960 the city. Saint Mark's Square historic buildings. 351 00:16:50,120 --> 00:16:55,120 Speaker 2: We saw permanent damage to centuries old structures, widespread electrical failures. 352 00:16:55,480 --> 00:16:57,480 Speaker 3: The very fabric of the city was at risk. 353 00:16:57,559 --> 00:17:01,279 Speaker 1: So the city responded with this massive, multi billion dollar project, 354 00:17:01,799 --> 00:17:03,519 the may Dell Flood Barrier System. 355 00:17:03,639 --> 00:17:07,240 Speaker 2: It's an incredible feat of engineering designed to physically block 356 00:17:07,279 --> 00:17:10,680 the lagoon with these massive submerged gates that rise during 357 00:17:10,759 --> 00:17:11,400 high tides. 358 00:17:11,519 --> 00:17:12,960 Speaker 1: But it's not a permanent solution, is. 359 00:17:12,920 --> 00:17:16,160 Speaker 2: It No, because it only addresses the external rising sea, 360 00:17:16,319 --> 00:17:20,400 not the internal sinking land. Venice has its own subsidence issues, 361 00:17:20,519 --> 00:17:22,799 and the most system has limits. You can't just use 362 00:17:22,839 --> 00:17:23,319 it every day. 363 00:17:23,359 --> 00:17:25,240 Speaker 1: Why not? If it works, why can't they just keep 364 00:17:25,279 --> 00:17:25,759 it closed? 365 00:17:26,079 --> 00:17:29,440 Speaker 2: That's the critical compromise. If you seal the lagoon too often, 366 00:17:29,519 --> 00:17:32,920 you stop the natural tidal fleshing that's essential for cleaning 367 00:17:32,920 --> 00:17:37,279 the water for the ecosystem. The lagoon becomes stagnant. 368 00:17:36,759 --> 00:17:39,880 Speaker 4: An ecological choke hold, a different kind of disaster, And 369 00:17:39,960 --> 00:17:42,440 the models show that by twenty fifty, sea level rise 370 00:17:42,480 --> 00:17:45,480 combined with subsidence will mean they'd have to operate the 371 00:17:45,519 --> 00:17:49,519 MOST systems so frequently that the cost, economic and ecological 372 00:17:49,559 --> 00:17:50,799 become unsustainable. 373 00:17:51,079 --> 00:17:54,640 Speaker 1: So even with the barriers frequent flooding becomes unavoidable. 374 00:17:54,759 --> 00:17:57,359 Speaker 2: It does, and the chilling implication here is that parts 375 00:17:57,359 --> 00:17:59,920 of Venice might still exist, but they'll function more like 376 00:17:59,880 --> 00:18:02,960 aquarium than a city. They might have to permanently seal 377 00:18:03,000 --> 00:18:06,359 off entire sections. It's a tragedy where the act of 378 00:18:06,400 --> 00:18:09,559 preserving its past threatens its future as a living city. 379 00:18:09,720 --> 00:18:12,960 Speaker 1: From the Adriatic to the Mediterranean, we find another historical 380 00:18:13,039 --> 00:18:16,519 city facing a crisis that's less about sinking and more 381 00:18:16,519 --> 00:18:21,079 about literal erosion. You can see happening today Alexandria. 382 00:18:20,680 --> 00:18:24,160 Speaker 2: Egypt, founded over twenty three hundred years ago by Alexander 383 00:18:24,200 --> 00:18:27,720 the Great, a crucial center for ancient empires. Today it's 384 00:18:27,759 --> 00:18:30,039 one of the most threatened coastal cities in the entire 385 00:18:30,079 --> 00:18:30,960 Middle East. 386 00:18:30,799 --> 00:18:33,160 Speaker 1: A metropolis of over five million people. 387 00:18:33,400 --> 00:18:37,559 Speaker 2: And the crisis isn't about projections a generation away. It's 388 00:18:37,559 --> 00:18:41,599 happening right now. Satellite data shows parts of the coastline 389 00:18:41,640 --> 00:18:45,519 are eroding rapidly, and the Nile Delta itself is sinking 390 00:18:45,720 --> 00:18:49,279 for reasons similar to New Orleans. The Aswan High Dam 391 00:18:49,480 --> 00:18:50,880 traps the silt up river. 392 00:18:51,000 --> 00:18:55,759 Speaker 1: So we're seeing tangible immediate impacts. Widespread salt water intrusion, 393 00:18:55,880 --> 00:18:58,119 damaging roads and buildings. 394 00:18:57,599 --> 00:19:02,519 Speaker 2: Right, and the sources mentioned specific tanable losses. Recent storms 395 00:19:02,559 --> 00:19:06,960 causing damage that wouldn't have happened decades ago, Collapsed cemeteries, 396 00:19:07,319 --> 00:19:10,119 beaches that have just vanished. You can literally watch history 397 00:19:10,160 --> 00:19:11,200 being washed into the sea. 398 00:19:11,319 --> 00:19:14,599 Speaker 1: The Egyptian government has responded with concrete barriers, but that 399 00:19:14,640 --> 00:19:17,559 can sometimes just push the problem down the coast accelerate 400 00:19:17,599 --> 00:19:18,400 erosion elsewhere. 401 00:19:18,400 --> 00:19:21,319 Speaker 2: Exactly, and as profound as that loss of heritage is, 402 00:19:21,680 --> 00:19:24,720 we have to pivot to the immense human cost when 403 00:19:24,720 --> 00:19:30,039 this environmental threat meets explosive population density, the population collision exactly, 404 00:19:30,559 --> 00:19:35,200 This creates the potential for displacement on a terrifying global scale. 405 00:19:35,400 --> 00:19:38,240 Speaker 1: Let's start with Manila in the Philippines. This city just 406 00:19:38,319 --> 00:19:41,680 perfectly encapsulates that collision. It's one of the world's most 407 00:19:41,680 --> 00:19:43,920 densely populated and flood prone. 408 00:19:43,720 --> 00:19:47,559 Speaker 2: Cities, and just like Jakarta, the real local crisis is 409 00:19:47,599 --> 00:19:51,240 the land disappearing from underneath the residence. It's a textbook 410 00:19:51,240 --> 00:19:53,920 example of subsidence combined with population pressure. 411 00:19:54,000 --> 00:19:57,920 Speaker 1: We see that groundwater extraction issue again, but just amplified 412 00:19:57,960 --> 00:20:00,839 by this sheer density. Land has lef towered by several 413 00:20:00,880 --> 00:20:02,559 feet over the past century. 414 00:20:02,200 --> 00:20:06,000 Speaker 2: Which means coastal flooding reaches much further inland. It amplifies 415 00:20:06,079 --> 00:20:09,160 the damage from every single typhoon, every heavy rain. 416 00:20:09,319 --> 00:20:11,000 Speaker 1: And what does that mean for daily life for the 417 00:20:11,039 --> 00:20:14,440 thirteen million people in Metro Manila. It's a grim picture. 418 00:20:15,160 --> 00:20:17,680 Residents using boats on what used to be roads. 419 00:20:17,759 --> 00:20:23,720 Speaker 2: Schools, closing businesses, shutting down infrastructure, constantly water logged. Their 420 00:20:23,799 --> 00:20:26,440 lives are functionally defined by the water level. It's not 421 00:20:26,480 --> 00:20:29,480 an emergency, it's just the baseline reality, and. 422 00:20:29,480 --> 00:20:34,240 Speaker 1: The twenty fifty projection is a true humanitarian nightmare. The 423 00:20:34,319 --> 00:20:37,680 models project that parts of Metro Manila will face permanent 424 00:20:37,720 --> 00:20:39,440 inundation during high tides. 425 00:20:39,839 --> 00:20:43,680 Speaker 2: Permanent, not just flooded, but permanently underwater during high tides. 426 00:20:44,039 --> 00:20:46,480 These areas will no longer be functional neighborhoods. 427 00:20:46,519 --> 00:20:48,240 Speaker 3: They'll be tidal flats. 428 00:20:48,039 --> 00:20:52,160 Speaker 1: Which raises a huge logistics question. If millions of residents 429 00:20:52,160 --> 00:20:55,640 are displaced, where do you move them in an already 430 00:20:55,680 --> 00:20:57,480 densely populated island nation. 431 00:20:57,720 --> 00:21:00,640 Speaker 2: That is the crucial question, and the answer is rarely 432 00:21:00,759 --> 00:21:04,519 clean or orderly. This same dynamic applies just as intensely, 433 00:21:04,599 --> 00:21:06,960 maybe more so, to Lagos Nigeria. 434 00:21:07,000 --> 00:21:10,240 Speaker 1: What are the fastest growing megacities in the world. Lagos 435 00:21:10,319 --> 00:21:13,920 is the ultimate collision point of rapid, unmanaged population growth 436 00:21:14,200 --> 00:21:16,240 and extreme environmental vulnerability. 437 00:21:16,519 --> 00:21:19,559 Speaker 2: Millions of people in Lagos live in extremely vulnerable, low 438 00:21:19,640 --> 00:21:22,559 lying coastal areas, massive and formal settlements. 439 00:21:22,599 --> 00:21:25,200 Speaker 1: And what's crucial here is the interaction between that development 440 00:21:25,480 --> 00:21:26,880 and the environmental degradation. 441 00:21:27,359 --> 00:21:31,240 Speaker 2: We have to look at the unintended consequences. Land reclamation 442 00:21:31,359 --> 00:21:36,000 projects intended to create new, modern, safe areas for business, 443 00:21:36,079 --> 00:21:39,839 like the Eco Atlantic project, they've actually increased the city's 444 00:21:39,920 --> 00:21:43,720 risk by altering natural waterflow. When you fill in wetlands 445 00:21:43,720 --> 00:21:46,960 to build up, you disrupt the natural drainage and storm 446 00:21:47,000 --> 00:21:48,799 buffer systems for the adjacent areas. 447 00:21:48,880 --> 00:21:51,599 Speaker 1: So you solve one problem, but you create a new 448 00:21:51,680 --> 00:21:54,440 and profound one for the older existing. 449 00:21:54,000 --> 00:21:58,359 Speaker 2: Settlements, precisely a self inflicted risk multiplier, and the most 450 00:21:58,480 --> 00:22:02,920 vulnerable are those informal settlements built without protection or drainage. 451 00:22:02,960 --> 00:22:06,480 By twenty fifty, scientists project widespread coastal flooding that will 452 00:22:06,480 --> 00:22:10,759 displace millions. Lagos is growing at an incredible rate directly 453 00:22:10,759 --> 00:22:11,759 into the rising water. 454 00:22:12,200 --> 00:22:15,680 Speaker 1: We've painted a really sobering picture here sinking land, porous rock, 455 00:22:15,839 --> 00:22:20,000 geopolitical surrender, massive population threats we have. So now let's 456 00:22:20,000 --> 00:22:22,160 turn to the city that has fought this battle the 457 00:22:22,200 --> 00:22:25,000 longest and the hardest, the one that provides a benchmark 458 00:22:25,039 --> 00:22:28,279 for what's possible and crucially, what his limits are. We 459 00:22:28,359 --> 00:22:29,640 had to discuss Rotterdam. 460 00:22:29,839 --> 00:22:34,559 Speaker 2: Rotterdam is the ultimate technological fortress. The Netherlands very existence 461 00:22:34,680 --> 00:22:38,000 is a millennia long fight against the sea. They have 462 00:22:38,079 --> 00:22:41,799 the most advanced flood defense system in the world, the Delta. 463 00:22:41,480 --> 00:22:45,720 Speaker 1: Works, including the massive Maizelant Barrier, this huge gait that 464 00:22:45,759 --> 00:22:49,119 protects Rotterdam by swinging shut across the waterway. 465 00:22:49,279 --> 00:22:52,680 Speaker 2: This is a city sitting largely below sea level, protected 466 00:22:52,680 --> 00:22:57,559 by this colossal, multi layered system of barriers, dikes and 467 00:22:57,680 --> 00:23:03,160 immense pumping stations. Netherlands invests billions every single year just 468 00:23:03,240 --> 00:23:03,920 to maintain it. 469 00:23:04,039 --> 00:23:06,480 Speaker 1: They're defining what the peak of human intervention looks like. 470 00:23:06,559 --> 00:23:09,440 Speaker 2: And yet even here in the best defended place on Earth, 471 00:23:09,519 --> 00:23:13,319 the engineers themselves acknowledge there are limits. The sources show 472 00:23:13,359 --> 00:23:16,119 that as sea level rise projections get worse, the pressure 473 00:23:16,200 --> 00:23:17,720 on these defenses increases. 474 00:23:18,079 --> 00:23:20,559 Speaker 1: So systems like the Maslond Barrier, which were designed for 475 00:23:20,680 --> 00:23:24,920 occasional use during a severe storm, may need to operate constantly. 476 00:23:24,960 --> 00:23:28,119 Speaker 2: By mid century, that shift from occasional defense to constant 477 00:23:28,119 --> 00:23:31,160 life support just fundamentally changes the sustainability equation. 478 00:23:31,359 --> 00:23:33,400 Speaker 1: It becomes chronic maintenance, not preventative. 479 00:23:33,680 --> 00:23:37,359 Speaker 2: Think about the logistical and financial strain running billion dollar 480 00:23:37,440 --> 00:23:42,440 machinery non stop, plus closing a barrier constantly disrupts shipping, 481 00:23:42,640 --> 00:23:44,799 and Rotterdam is one of the busiest ports in Europe. 482 00:23:45,400 --> 00:23:48,440 The defense mechanisms start to undermine the very economy they 483 00:23:48,440 --> 00:23:49,359 were built to protect. 484 00:23:49,640 --> 00:23:52,680 Speaker 1: That's the paradox of Rotterdam. By twenty fifty, the city 485 00:23:52,759 --> 00:23:56,839 is expected to remain standing, but only through extreme, ongoing intervention. 486 00:23:57,400 --> 00:24:01,039 It shows what's physically possible when a wealthy commits vast 487 00:24:01,119 --> 00:24:02,359 resources to the problem. 488 00:24:02,400 --> 00:24:05,000 Speaker 2: But it also shows how fragile even the best defenses 489 00:24:05,039 --> 00:24:07,119 can be and at what cost. It gives us a 490 00:24:07,160 --> 00:24:09,920 price tag, a benchmark for what it takes to defeat 491 00:24:09,960 --> 00:24:11,720 this dual calamity. 492 00:24:11,240 --> 00:24:13,480 Speaker 1: And we have to apply that benchmark to the rest 493 00:24:13,480 --> 00:24:13,960 of the world. 494 00:24:14,039 --> 00:24:17,200 Speaker 2: So if we synthesize everything we've looked at, from Jakarta's 495 00:24:17,279 --> 00:24:21,599 drained aquifers to Miami's porous Rock to Venice's sinking foundations. 496 00:24:21,799 --> 00:24:23,079 Speaker 3: The central theme is clear. 497 00:24:23,240 --> 00:24:24,480 Speaker 1: The threat isn't uniform. 498 00:24:24,759 --> 00:24:27,519 Speaker 2: No, it is defined by a local factor, whether that's 499 00:24:27,559 --> 00:24:31,400 subsidence or geology that dramatically amplifies the global factor of 500 00:24:31,400 --> 00:24:34,119 sea level rise. We have to see twenty fifty not 501 00:24:34,240 --> 00:24:37,240 as a distant projection, but as a hard operational deadline 502 00:24:37,240 --> 00:24:38,799 for adaptation or relocation. 503 00:24:39,200 --> 00:24:42,880 Speaker 1: The timelines are collapsing. We've seen cities where land subsadan's 504 00:24:42,880 --> 00:24:45,799 forced the government to literally move its capital. We've seen 505 00:24:45,839 --> 00:24:50,559 others where survival requires billions in annual investment just to 506 00:24:50,599 --> 00:24:54,000 stay dry. The sheer scale of these interventions is what 507 00:24:54,200 --> 00:24:57,839 must stick with us. The cost is staggering. 508 00:24:57,400 --> 00:25:00,559 Speaker 2: And the Rotterdam case provides the ultimate be benchmark for 509 00:25:00,599 --> 00:25:05,960 survival extreme ongoing intervention. It shows what's possible, but with 510 00:25:06,000 --> 00:25:07,359 an astonishing. 511 00:25:06,799 --> 00:25:09,559 Speaker 1: Resource cost, which brings us to a really provocative thought. 512 00:25:09,880 --> 00:25:12,839 We've seen cities sinking under their own weight, others being 513 00:25:12,839 --> 00:25:15,759 eroded back into the sea. The question is last about 514 00:25:15,920 --> 00:25:18,319 if we can save every threat in city, and more 515 00:25:18,319 --> 00:25:21,680 about who gets that extreme ongoing intervention right. 516 00:25:21,839 --> 00:25:24,680 Speaker 2: Not every nation has the engineering budget of the Netherlands. 517 00:25:24,799 --> 00:25:27,599 Speaker 1: So if you had to globally allocate the billions required 518 00:25:27,599 --> 00:25:30,960 for these constant battles for survival. What measure do you 519 00:25:31,000 --> 00:25:32,440 think should be the deciding factor? 520 00:25:32,559 --> 00:25:36,319 Speaker 2: And that's the difficult choice facing policymakers. Do you prioritize 521 00:25:36,319 --> 00:25:38,680 cities based on the raw speed of the threat, the 522 00:25:38,720 --> 00:25:39,759 subsidence rate. 523 00:25:39,839 --> 00:25:42,640 Speaker 1: Or do you prioritize them based on the scale of 524 00:25:42,680 --> 00:25:46,119 the human impact, the population density, the number of people 525 00:25:46,119 --> 00:25:47,039 who will be displaced? 526 00:25:47,240 --> 00:25:51,119 Speaker 2: Or is it the historical or economic significance of the metropolis. 527 00:25:51,160 --> 00:25:54,119 Speaker 1: We've discussed cities where technology saves them and cities where 528 00:25:54,160 --> 00:25:57,559 the government accepted defeat. If you were in charge of 529 00:25:57,559 --> 00:26:03,400 allocating those billions, what measures sidence rate, population density, historical significance, 530 00:26:03,480 --> 00:26:06,319 or something else entirely do you think should be the 531 00:26:06,359 --> 00:26:09,640 deciding factor in which cities fight for survival by twenty. 532 00:26:09,480 --> 00:26:12,440 Speaker 2: Fifty A difficult question to ponder. Thank you for joining 533 00:26:12,480 --> 00:26:14,680 us on this vital and urgent exploration. 534 00:26:14,799 --> 00:26:16,720 Speaker 1: We'll catch you next time on thrilling Threads.