Alright, please bear with me on this one and thank you MASSIVELY for taking a look. Had a dream, a very sci-fi dream and for whatever reason I need to write it out. It won’t go away but, I also want SOME level of scientific logic behind the events. So, in the dream Jupiter got a swift kick in the rear which drastically altered its orbit. For whatever reason my brain was like “Sure dude that’ll totally cause rapid flooding of the Earth and not some other extinction level calamity.” and here we are now. How can I logically cause the Earth’s sea level to rise enough per hour that in two to three days it would be a water world? I mean uninhabitable water world. Next up is what cosmic event could I use to swing Jupiter out of its orbit? Are we talking really angry aliens or could a natural event actually cause this change? Should I just leave Jupiter alone? Not surprisingly Earth was in Jupiter’s orbit with zero explanation because dreams. Anyway thanks a bunch for any time you spent on this one. I look forward to any and all responses.
A black hole or rogue planet could wander past our solar system and throw Jupiter out of orbit. I have a feeling anything that massive rolling by will screw us too. I’m not sure how that would affect sea levels.
Yeah that’s what I’m really trying to figure out. How not to die horribly while still being plausible.
If Jupiter got close enough, it's gravity could cause some kind of massive super tides that would basically pull all of the oceans to one side of the Earth, this would basically be like worldwide flooding, because all of the continents, (with maybe the exception of Antarctica) would be covered by a massive tidal high as the earth rotated. That would probably cause other problems, too, though, like increased tectonic activity and whatnot.
Other than that tide idea above, there's really no way to do it; Earth doesn't have enough water. Here's a video that shows the changes if all the ice on Earth melted, comment says that it would result in a 216 foot sea level rise. That sounds like a lot, but when you see how little some of the coastlines are altered (okay, Florida gets completely submerged), you'll find that there is still a lot of notionally habitable land. Of course, the climate change that would come with such an event would be off the scale of comprehensibility, but with some warning, drowning wouldn't be an issue except in certain areas. ETA: Here's Bill Nye talking about the topic:
Maybe the solar system being out of whack causes impacts from big ice comets? Assuming they hit at a shallow enough angle to melt or break up before directly impacting the surface.
It would still raise the temperature a lot, all that energy is going to turn into heat no matter what the angle .
You can't - there isn't enough water on earth to flood the entire planet even if the ice caps melted fully
You could do a time laps into the far future when the core of the earth cools, preventing the regeneration of the continents so that the ocean can wear them down. Or would we lose the magnetosphere, then the atmosphere, and then the oceans, to the solar wind before the continents could erode? Or, will the sun have already increased in intensity to the point that we lose our oceans to the straight up heat? hmmmm
You might be able to gain a bit more depth if you leveled out the ocean floor a bit, though. If tectonic activity filled in a couple of deep sea trenches, then we could probably get a few more meters of water, and that would probably lower some of Earth's high spots, so we'd need less water to actually flood the thing.
OTOH, if you decide to just handwave and make it happen (that's not wrong, I think that scientific accuracy is over-emphasized on this forum at times. There are some great stories out there that don't hold up realistically at all), check out footage of the 3/11 tsunami to see what happens when the sea pays a visit. Some graphic imagery, so I'm going to wrap this video clip in a spoiler: Spoiler: 2011 Japan Tsunami video
Yeah, Earth doesn't have much water astronomically speaking and there is no way to add more. Even flattening it out would probably not let you cover it. You could cover the entire planet in water if you freeze it though, since ice doesn't really flow much. This happened about 500 million years ago in a geological period called "Snowball Earth" for a variety of reasons, the most important being a massive decrease of CO2. There'd also be no way to kick a planet the size of Jupiter anywhere without kicking everything else around. Jupiter is the dominate object in the solar system and has more mass than everything else combined. It's the gravitational anchor that holds our system together. Orbital dynamics are finicky things and even tiny changes can cause wild changes to orbits. Orbital dynamics also change over the course of thousands of years.
The simplest solution would seem to me to be to set the story in another solar system. You could them arrange the planets however you want, cause the event which kicked the larger planet out of its orbit and affected the tides of the planet orbiting it, and also have the smaller orbiting planet made up of enough water to completely flood the surface. The problem with this is where the water actually exists before this event. Water wants to spread out in liquid form. So if it’s all just lying there on the surface, then it will spread out and cover the surface if there’s enough of it. That means the planet would be flooded no matter what. If the water is in deep oceans, then you have the exact same problem as on Earth - there won’t be enough to flood the entire surface. The only way around this that I can think of would be if the planet had vast quantities of ice (considerably more than on Earth) - enough to flood the entire surface if melted. The planet as a whole would probably need to have a lower temperature than Earth to account for the formation (and sustaining) of all that ice. Perhaps it is in geostationary orbit with its star, so one side is constantly dark (and cold), allowing all that ice to form. A gravitational event like a larger planet moving towards a smaller one wouldn’t in itself cause ice to melt. But it could perhaps affect the orbit of the smaller planet, maybe cause it to rotate so that the dark side of the planet get exposed to the star which begins thawing the ice. Bear in mind also that melting ice is only one issue associated with alterations to the orbit of a planet. It would affect the movement of the planet’s core, its rotation around its parent, proximity to a star, and all the associated complication regarding climate etc. Not to mention it could be knocked off a stable orbit and spiral towards (or away from) the solar system’s star. Which would obviously be disastrous.
Oh one note about the above - sudden exposure to heat from a star wouldn’t cause rapid flooding, which is what you specified. The planet would take time to rotate, and then you’d have to wait for the ice to actually melt. The rise in sea level would be gradual. Also, while the iced up side is exposed to the star, the previously light side of the planet would be in darkness which would bring its own issues. I can’t actually see any way that a whole planet could be flooded rapidly. To be honest I think this implausible, unless you introduce a science fiction element such as a futuristic weapon which is deliberately used to thaw large amounts of ice in an instant, or which delivers vast quantities of water to the planet, or created fluid from solids and gases already on the planet. But then you’re probably not writing the same story any more.
Agreed, you’re talking about a planet wide change. Such a thing happens at the fastest over the course of a century. We’ve already passed the point of no return with climate change, but we won’t notice any real major change for a hundred years still. To be clear though, there are plenty of places for water to hide. There is more water inside of our planet than on its surface (by a lot.)
Not to pile on, but: not only this, but it would take at least thousands of years to get as much water as you'd need (using the comets idea).
*hundreds of millions Most of the comet impacts our planet has suffered happened during a period called the Late Heavy Bombardment when comets were constantly pummeling the Earth. This continued for about 400 million years and is responsible for the majority of the water on Earth.
I like this angle, Earth develops a huge bulge under the Pacific sea floor and displaces all that water.
Or just dial down the hard science aspect, after all, Waterworld had the same premise and was a smashing success. Hmm, not sure. But not everything needs to be The Martian.