On Tsunamis and Tornadoes

“And the most devastating tsunami of all time was triggered by an earthquake off the coast of Indonesia. December 26th, 2004. 230 000 people lost their lives…”

The children had switched onto the National Geographic channel; we had previously watched the feature on tsunamis some time back, but we wanted to watch it again. That tsunami had hit the coast of Thailand a little under 3 months after we visited; we remembered watching the news at the time, seeing some of the places we’d visited being washed away. Phuket. Kho Phi Phi. How would we have reacted if we were there? What chance would we have had at 7 am in the Seaview Phatong on the beach in Phuket, ground floor? Would we have been asleep, or would the jet lag have got us up earlier in the morning? Would we have looked at the receding waters and just watched in amazement?

The most startling fact I wanted to check was the height of the wave that came out of a small inlet in Alaska in 1960, as a result of a landslide. A father and son were out in a fishing boat, they felt the earth rumble – an earthquake, and then heard an explosion as the landslide fell into the sea, causing a huge wave. He then saw a wave which he estimated to be 1000 feet high coming towards him; he started his engine and went straight into the wave. His anchor line snapped off as the boat was lifted into the wave; he saw trees down below off the stern of the boat. He managed to crest the wave and survive to tell the story. The wave was measured at 1720 feet (as compared to a little over 100 feet for the Indonesian tsumani). This figure, I think, relates to the height above sea level which the water went up the land; in the case of the landslide, there was a huge pocket of air that was behind the wave which pushed it up very high.

The program ended with a possible future scenario for the biggest Tsunami ever to occur in modern history. The potential place: Honolulu. A massive tsunami could be triggered by a landslide from the Big Island after a volcanic eruption which would literally blow off the sides of the island. Hundreds of cubic miles of land could fall into the sea causing a massive tsunami the likes of which have never been seen before: it would be directed at, among other places, Honolulu which is 300 miles away to the north west. Honolulu would be decimated, destroyed. People would die in massive numbers.

Next on National Geographic channel: tornadoes. Tornado alley is a strip of land in the US which is hit by hundreds of tornadoes each year; the worst of which was in Oklahoma City a few years ago – 60 people were killed, many injured. Although the forces of the winds are high – there was video of trucks and semi-trailers being lifted into the air, the debris which is flung around and around and finally out of the tornado causes a huge amount of damage. Scientists are figuring out how shelters and houses need to be made safer, more resilient against the forces of nature. They drop cars onto slabs of concrete and figure out that it’s best if there’s a steel mesh on the undersurface, not just rebar through the concrete. They fire two by four poles at brick walls and find that they need to be reinforced with a concrete wall inside the brick exterior.

People chase tornadoes, measure the wind speed using doppler, trying to understand their behaviour. What would happen, the feature ends, if a mega-tornado hits the largest city in Tornado Alley? The devastation would be huge, death toll high. And the name of the city? – Dallas.

That was enough for us. TV off, time to get to sleep. We had to be up early the next morning, to get to the airport to catch our connection. Dallas to Honolulu.