In the modern world there is sometimes a complacency that we have somehow conquered nature. This belief can be destroyed in moments when the planet reminds us this is not the case, and in the most brutal ways. Of all these tsunamis are one of the most terrifying and devastating of all natural disasters.
The terms tsunami and tidal wave are often used interchangeably, although these actually describe different phenomena. Tsunamis are ocean waves which are created by the sudden movement of land; this is most commonly from an earthquake but can also be caused by volcanic eruptions and landslides.
Whatever the cause the result is a huge surge of water that travels across the open ocean at vast speed. Tsunamis travel at around 500 mph (800 km/h) and will travel the width of an ocean without losing much of their power. They are barely noticeable until they hit shallow coastal waters where the massive volume of water is concentrated upwards.
Contrary to the popular image of the tsunami the actual wave may appear fairly unimpressive. It may seem like the sea level is rising rapidly and sweeping everything before it. On occasions though the wave itself can be immense, over 100ft (30m) in some cases. However, this pales into insignificance compared to mega-tsunamis (see bottom of article) that can be over 10 times this height.
10. Messina, Italy 1908
When we think of tsunamis we tend to associate them with the Pacific / Indian Ocean “Ring of Fire” with its volcanic islands and ever shifting tectonics. Although this is certainly where the majority of tidal waves have occurred it is by no means the only region affected. In fact virtually anywhere with a coast is susceptible to tsunamis of one form or another.
As you see from this list Europe has had its fair share of hugely destructive tsunamis with few other natural disasters wreaking the same amount of death and destruction. The most recent of these happened early in the morning 3 days after Christmas 1906 in the waters between Sicily and mainland Italy.
The tsunami was triggered by a powerful earthquake; the deadliest ever witnessed in Europe killing anywhere up to 200,000 people and more-or-less obliterating the coastal cities of Messina and Reggio Calabria, on the other side of the straits. Survivors of the earthquake poured out onto the streets to avoid falling debris, many choosing the seafront as the safest place.
10 minutes after the quake, at 5.30am the water on both sides of the straits suddenly drained from the shore. Minutes later three tsunamis measuring up to 39ft (12m) struck killing thousands, both in the cities and further along the coast. Given the overall scale of destruction the exact death toll is not clear but the most conservative estimates are around 2,000, but the figure was likely much higher than this.
9. Valdivia, Chile 1960
On 22nd May 1960 the most powerful earthquake ever recorded occurred in southern Chile. Measuring up to 9.6 on the Richter scale this enormously powerful quake unleashed a tsunami that wrought devastation across the Pacific.
Within 15 hours of the earthquake a 35ft (11m) wave struck Hilo in Hawaii. Despite a tsunami warning being issued 61 people were killed. Around 22 hours after the earthquake the tsunami reached the shores of Japan where, although somewhat diminished, still managed to kill 142 people.
China, the Philippines, New Zealand and Australia were all affected by the tsunami but it was in Chile where most of the 6,000 casualties occurred. Waves here were recorded at up to 80 feet (25m) and brought destruction to much of the country’s coast.
8. Ryūkyū, Japan 1771
If any one country has suffered disproportionately from tsunamis it is Japan. Even the word itself is Japanese. Virtually every other major tsunami seems to have centered around this country and given its geology and geography this will continue to be the case.
It seems like the 18th century was a particularly bad century for the country with a spate of violent earthquakes followed by deadly tsunamis. It is difficult to say if the 1771 tsunami which struck the tropical southern islands of Japan was worse than the 1707 Hōei tsunami or 1792 Unzen tsunami. All probably killed in excess of 10,000 people, though the historical records are not completely reliable.
The Ryukyu tsunami was triggered by what was named the “Yaeyama Great Earthquake”, although in reality this was not particularly powerful and occurred around 25 miles (40km) off the coast of Ishigaki Island causing little immediate damage. The quake struck at around 8am but within a matter of minutes a powerful tsunami ripped through the southern island chains of Okinawa.
Ishigaki bore the brunt of the wave and while estimates vary dramatically it was huge – anywhere from 125ft (40m) to over 250ft (80m) high. The result was massive death and destruction. Not only where over 13,000 people killed throughout the Yaeyama and Miyako Islands, but the inundation of seawater ruined much of the agricultural land. The tsunami was followed by an outbreak of malaria and crop failures with the eventual population being only a third of what it had been.
Today the idyllic sandy beaches and coastline of the islands are dotted with random rocks here and there. These are said to have been deposited here by the tsunami. None is more impressive than Obi Rock on Shimoji island. This house-sized rock was deposited at the top of a 35ft (11m) cliff.
7. Arica, Chile 1868
As we have already established, Chile is certainly capable of producing a good deal of seismic activity. Indeed it is situated on the infamous “Ring of Fire” that encompasses the Pacific Ocean.
On the afternoon of August 13th 1868 all was quiet in the busy port town of Arica. Then at around 5pm, without warning a massive earthquake struck devastating the city. This was followed by a more powerful aftershock which virtually levelled the port; it is said that only two buildings were left standing after the quake.
The epicentre of the earthquake had been some distance offshore in the Peru-Chile Trench and is estimated to have had a magnitude of around 8.5 to 9. These are exactly the conditions to spawn a tsunami and this is exactly what happened. 52 minutes after the earthquake had struck the port was battered by a 39ft (12m) wave.
Witnesses described the wave of not being so much a wall of water, but as the sea level falling then rising, engulfing everything in its path. But worse was to come; 20 minutes later an even bigger tsunami hit. This was estimated to be over 50ft (16m) and completed the job of the destruction of Arica.
It was not just those in the city that perished – the busy harbour was full of boats and ships, many with crew on board. This was the case with the steamer USS Wateree. Like the other boats in the harbour the crews knew they would be better off out to sea after the earthquake, however, there wasn’t a breath of wind. This shouldn’t have been a problem for the two steamships in port, unfortunately the Wateree was undergoing repairs to her boilers and the other steam vessel, the America was low on coal.
Of all the ships in the harbour the Wateree came off best although she never sailed again. After her anchors broke the ship was washed over half a mile inland a deposited there relatively undamaged along with nearly all her crew. The boilers are all that remains of the ship and are still here as a monument.
The tsunamis devastated much of the coast of northern Chile and southern Peru, and this is where most of the casualties occurred. But the effects were not limited to the South American coast. Many villages on Chatham Island near New Zealand were washed away by a 10m (30ft) wave and considerable damage caused on mainland New Zealand. Hawaii was affected by the waves and even Japan suffered some damage almost a day later.
6. Japan – Tōhoku 2011
The 2011 Japan tsunami began with an massive earthquake just off the coast of Tōhoku in northern Japan. With a magnitude of 9 it was the most powerful earthquake ever to have hit Japan, a country relatively well known for earthquakes. The quake caused wide-ranging geophysical effects; parts of northeast Japan shifted as much as 8ft (2.5m) closer to North America, a 250 mile (400km) stretch of coastline dropped almost 2ft (0.6m), numerous undersea landslides occurred, and most significantly, a 11o mile (180km) section of the seabed rose by 18-25ft (6-8m) unleashing a powerful tsunami.
The tsunami made land around an hour after the earthquake and the rest is history as they say. Unlike any other disaster on this scale the horrific destruction was broadcast virtually live as it happened. I recall being transfixed to the TV watching aerial film of cars trying to escape the relentless wall of water as the sea engulfed the land.
Given this is the modern world with advanced warning systems and communications the loss of life was quite shocking. The fact is no one imagined the scale of the tsunami that had been unleashed. Walls built to defend from such an event were quickly overtopped whilst people who thought they were safe on higher ground were not.
In some towns the onslaught of debris-filled water was as high as a three-storey building. Most places affected were hit by waves well over 16ft (5m) whilst the highest reported tsunami height was 133ft (40.5m) in Miyako, Iwate Prefecture. This is the highest measurement ever recorded in Japan and illustrates the severity of the disaster.
Although the tsunami did travel to the four corners of the Pacific damage was relatively light and casualties almost non-existent.