Tsunamis are Deadly Water Events The oceans are rising. The levels are very slight but increasing. The polar ice is melting. Global warming is starting to take its toll. The average temperature is increasing. We have talked about global warming before, but did we see the beginning of it with the tsunami that swept part of Indonesia? In case you don't know what I am talking about, on December 26, 2004 there was the most powerful earthquake in 40 years in the Indonesian region. But fierce as that earthquake was, it was the huge tidal wave that killed over 27,000 people and had displaced over 1,000,000. The question is, if we didn't have global warming and the ocean was not as high as it is now, would the wave have been a lot less severe? Let’s take a look at what the sea level was about 100 years ago. Australian National University scientists checked Roman fish pens that were dug into solid rock about 2,000 years ago. They are about 1.35 meters below the sea level today. Much of the reason for this increase in the ocean level relative to the pens, has to do with geological reasons such as land mass falling. The sea itself only rose 13 centimeters. So, the answer to our question is global warming didn't contribute very much to the height of the tsunami that swept over Indonesia and other areas. One of the things that did contribute to the amount of destruction is the fact Indonesia is composed of over 17,000 islands. Many places are in danger from this type of wave. Whether the reason is the land has decreased in height or the sea has risen really doesn't matter in these cases. The result is still the same, they are more vulnerable to being swept over by huge waves. An amazing fact is 75% of the world's population lives near water, usually within about 40 miles of the sea coast putting them in jeopardy. Tsunamis can be produced by several different methods. Undersea earthquakes produce many of them, but they can also be created by a landslide if it is large enough, or even by a volcanic eruption in the middle of the ocean. Sometimes tsunamis are not even noticed by ships. The reason for this is the water rises and falls so slowly as to be misperceived. When the water hits the shore however, it is devastating. What hit Indonesia and the surrounding areas was generated by an earthquake. This type of tsunami is also called a seismic sea wave. What is really scary is sometimes the tsunami can move incredibly fast, hitting speeds up to 600 mph across the ocean then usually drops in speed as it nears the shore line. These incredible speeds do not allow for an abundance of warning time, if any. In 1960 a tsunami formed near Chile. It killed over 5,000 people there then headed to Hawaii then Japan. They travel huge distances and no one is safe from their fury. In 1970 a cyclone with a tsunami killed 266,000 people in Bangladesh which was then East Pakistan. In 1977 a cyclone with a Tsunami killed 15,000 in India. In 1985 a cyclone and tsunami killed 10,000 in Bangladesh. In 1991 138,000 people died in Bangladesh when it was hit again by a cyclone and tsunami. As you can see, it is quite common for a cyclone and tsunami to hit the same area. Bangladesh seems to be singularly cursed as far as being hit with cyclones and tsunamis. The death count for this country is staggering. Just looking at the examples I cited for them, the total is 414,000 people dead, not to mention the injured. Sometimes tsunamis are called Tidal Waves, but have nothing to do with the tide. The tide is caused by the pull of the Moon on the Earth. It is also true the Sun has an effect on the tides, but it is only about half the effect exerted by the Moon. Tsunamis can hit anywhere and come without warning. A good example of this was in Alaska in 1964. Tsunamis struck the Kodiak Islands and killed 122 people. The waves there were estimated to be at least 35 feet high and they can get a lot bigger. Let’s hope that in the near future we figure out a method for early warning of such events or some way to either stop them or lessen their effect. Many people don’t realize the arctic ice melting is causing big chunks of ice to fall into the ocean. Maybe I should say they don’t realize the effects of this large portions of ice falling or sliding into the water can cause. There is always a danger to the world when huge ice shelves and large chunks of land fall into the water. One of these events could be a tsunami. It doesn’t always happen, but if a big enough chunk goes plunging into the ocean it creates waves and these waves can travel at hundreds of miles an hour creating a tsunami, as a matter of fact some have been clocked at 600 miles per hour. Just the fact a huge iceberg getting too close to a village or town can cause fears of a tsunami. In 2018 a large iceberg was threatening to swamp a tiny village in Greenland, but there were also fears a big piece would break off and fall into the water causing a tsunami. This tsunami probably would have only hurt the village since the iceberg was only 650 feet wide by 330 feet high, and by iceberg standards there have certainly been a lot of bigger ones floating around. When we talk about landslides causing tsunamis, one of the incredible things is even underwater landslides can do this. The reason is when water is violently displaced it cause waves and disturbances. Tsunamis can surprise people and they have done this many times in history. In 1898 a tsunami hit the Sanriku coast of northeastern Honshu, Japan and devastated it. It was hit again in the same spot in 1933 killing thousands of people. The largest tsunami ever recorded hit Lituya Bay in Alaska. It had a wave which was the incredible size of 1720 feet high. Sometimes water can be the great destroyer. Scientists are finding out the great flood was probably true because there are references to it in just about every culture. Could it have been caused by a giant tsunami?
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