I’m sorry but – this will happen
Just over seven months ago, I posted an item about the near-term probability of a catastrophic eruption of the Katla volcano on Iceland. Today, sadly, I think I have discovered that this might not be the worst natural disaster in human history (not to have happened yet).
Scientists believe that, when it happens, the Katla eruption could ultimately be responsible for the deaths of millions of people. However, there are many uncertainties; and a great deal of scope for deaths to be prevented. The same cannot be said for a mega tsunami originating in the Canary Islands.
La Palma is one of a group of Spanish volcanic islands off the coast of North Africa. The volcano of La Cumbre Vieja on La Palma erupted in 1949 and 1971. It is not like most other volcanoes; it is more like the Laki fissure on Iceland. Previous eruptions have been associated with earth movements; and it is now estimated that another eruption could send a large part of La Palma sliding into the North Atlantic ocean. In fact, it is estimated that another eruption could cause a landslide containing 500 cubic kilometres to slide into the ocean.
Contrary to popular myth, scientists are not prone to being alarmists. However, a wide variety of scientists are actively studying and modelling the consequences of another eruption of La Cumbre Vieja on La Palma.
At the end of this post you will find the YouTube video of the BBC/Discovery Channel production “Could We Survive a Mega Tsunami?” Similar to fears over an approaching ecological catastrophe arising from human activity, this fear over a catastrophe emerging from the Canaries is founded on science: It is not just the idle speculation of a bunch of doomsayers. There is evidence of previous tsunamis in the Canaries caused by previous landslides on the islands. What marks the landslide on La Palma (that has not happened yet) is the size of the area that could be affected (and the volume of material that could be mobilised).
The programme (video below) uses Hollywood style CGI, dramatic reconstruction and footage of previous tsunamis to great effect to tell the story of what is guaranteed to happen if the landslide occurs. This has been established using a combination of physical and computer modelling (you need to watch the video to appreciate the reality of all this).
Within 10 minutes, the mega tsunami – travelling at the speed of sound – would hit Gran Canaria, within 60 minutes Morocco, within 90 minutes Portugal, within 3 hours England; within 6 hours the Caribbean. Most devastating of all, however, by virtue of the geography, within 7 hours the entire length of the Eastern seaboard of the USA would be hit almost simultaneously.
Within minutes, social media would alert the World to the disaster but, it is thought, the USA would not take notice until its network of buoys in the North Atlantic indicated a tsunami was on its way. Worse still, psychologists reckon that even after being warned, 50% of urban Americans would ignore the danger (i.e. optimism bias and denial strike again).
In the city of New York, the authorities have already spent 10 years analysing the consequences of a mega tsunami from the Canaries, which will reach several kilometres inland, and have determined that the death toll will be significant. Along the eastern seaboard of the USA, 40 million people live within 40 km of the current seashore and 30 million of those people live within 10 metres of current sea level. By the time the tsunami makes landfall, it is likely to be at least 25 metres high. However, the main problem is that there will not be one wave, there could be as many as 10 waves; and each one has a very long wavelength – measured in hundreds of metres – so it will be like a river of water flowing inland. And what goes in must come out again; and when the water flows back out to sea again it is loaded with debris… Then you have the interruption to basic services, the breakdown of law and order; and the spread of disease… This will make what happened to Japan very modest by comparison.
One member of the US authorities estimates that there could be over 4 million casualties (I am not sure what he means by this). It seems clear, then, that this tsunami would make the death toll of the Indonesian tsunami (250 thousand) seem modest by comparison. Authorities in New York City reckon they could not cope with more than 600 thousand displaced people.
The collateral damage will also be extensive. The tsunami would knock out every single east coast port, which will trigger food shortages everywhere east of the Mississippi…
But enough from me. Watch the video. It will blow your mind…