So I'm starting a story right now that isn't non-fiction but idk if it could be classified as fiction. It's set on Earth in the USA, basically the main thing is that a tsunami occurs. I'm debating on whether or not if I should research about a real Tsunami and make up a family or just make up the whole thing.
- If you're writing about real people and real events, that's "non-fiction"/"journalism". If you write it in the style of a novel, it's "creative non-fiction".
- If you're writing about made-up people in real events, that's "historical fiction."
- If you're writing about made-up people in made-up events in the real world, that's "fiction." It might also be called "realist" or "realistic" fiction --"contemporary" if it takes place now or in the recent past, "historical" otherwise.
- If you're writing about a made-up world or impossible events, that's "fantasy." If you're writing about (arguably) plausible events in the future, that's "science fiction."
Even if the finished result is going to be wholly fictional, it will help give your work depth and realism if you research it extensively first. Learning the story of a real person in a real event can help you in creating your made-up version.
If your story is in the USA in the past it will be historical fiction. No doubt there is evidence of a number of large tsunamis in the present USA in the past, but if your story happens after the USA was founded the number will be smaller.
If your story is supposed to happen more or less in the present it will be contemporary fiction. Obviously, a tsunami, though unlikely, could strike any coastline, including those in the USA, at any time, though the odds of a tsunami at any specific time and place are very low.
If your story happens in a time that is clearly in the future when written (no matter how many years or millennia in the future) it is science fiction.
Since tiny, unnoticable, tsunamis happen all the time, and larger, barely noticeable tsunamis happen more rarely, and large tsunamis causing damage and death are much rarer, and gigantic tsunamis causing massive death and destruction are very, very rare, in eal life it might be a long time in the future before a tsunami large enough for the unknown purposes of your story strikes anywhere in the USA. So that gives you a jusification for making your story a science fiction story set in the distant future, if that is when you want to set it.
I note that the USA includes a number of inhabited and uninhabited islands in the Caribbean and the Pacific Ocean, and some of them have suffered from tsunamis.
Hilo, Hawaii is especially vulnerable to tsunamis, the configuration of land and shore there making them much stronger than in other regions of Hawaii. Hilo suffered two devasting tsunamis in 1946 and 1960.
When I met my uncle's third wife she said she was from Crescent City, California, and I asked about the tsunami there in 1964, she said she knew some of the people who were killed.
i once read about a large wave that deposited a boat near a Spanish mission near present day Los Angeles, CA. It was suggested that the wave was a large tsunami that penetrated far inland. This might be the wave in 1812.
On January 26, 1700, a large tsunami struck Japan. No earthquake was recorded in east Asia. Scientists have discovered that the tsunami was generated by the Cascadia subduction zone in the Pacific northwest of the USA, and many native communities along the pacific coast have oral traditions of a powerfull earthquake and massive tsunami generations before the commong of white men. And geological traces of the massive tsunami have been found in the Pacific northwest.
The Cascadia subduciton zone could possibly generate a magnitude 8 or 9 earthquake within the next century or two, generating tsunamis up to 80 to 100 feet (24 to 30 meters).
I note that on 9 July 1958, an earthquake loosened a vast amount of rock which slid into Lituya Bay, Alaska, and caused a tsunami reaching as high as 1,720 feet or 520 meters. I note that there have been other large tsunamis cause by landlides at Lituya Bay. Lituya Bay would be a good setting for a very local tsunami striking when vacationers are in fishing trips in the bay.
Since the Lituya Bay, Alaska tsunami was caused by a landslide into an enclosed body of water, any lake or river close to a mountain could produce a significant landslide-caused tsunami, even if it is hundreds or thousands of miles from the ocean.
On 9 October, 1963, an earthquake caused a massive landslide into the lake formed by the very high Valmont dam in Italy. The lake waters splashed over the dam and formed a tsunami 250 meters or 820 feet high in the valley, wiping out several villages below.
It seems to me that anytime a dam releases a vast flood water, that counts as a tsunami in the area below the dam, whether or not any earthquakes or landslides are involved. So the Johnstown Flood caused by a dam failure on May 31, 1889, could count as a tsunami hundreds of miles inland.
During the eruption of Mount St. Helens on 18 May 1980, a landslide into Spirit Lake caused a tsunami 260 meters or 823 feet high.
Here is a list of tsunamis striking parts of the USA.
Anda discussion of relative tsunami risks in different regions:
It is certainly possible for a major tsunami to strike the east coast of the USA and cause major devastion. There is a site discussing the slight possibility of a tsunami up to 300 feet high striking the east coast of the USA.
If such an extreme event happens millions will die. That should be a large engough disaster for most fictional purposes.
And there have been a few reports of much smaller but noticeable tsunamis or tsunami-like waves along the the eastern coast of the USA.