Tibetan plateau is the only land left?
Two words: Air pressure.
Wouldn’t the water just push all the existing air up with it?
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Three words: I don’t know.
Good question. Who would know something like that? Planetary geologist? Standard, run-of-the-mill, physicists?
I’m no physicist, but how’s this: Atmospheric pressure is a function of the weight of the air above you. If the total amount of air has not changed, and the total mass of the earth has not changed, then the only change would be the diameter of sphere that is covered by the same amount of air. So, there would be slightly less pressure at this new sea level.
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I see what you did there 
The increase in diameter would be 0.01%. (12742km + 15km), increasing the surface area of the earth by about 1.2m square kilometers (to 1,512,469,109.7587 km2), about 0.25%
This really brings home just what an unimaginable volume of water we’re talking about! But it doesn’t sound like the atmosphere gets much stretched-it’s already a much deeper ocean on top of it all.
80% of the atmosphere’s mass is within 10km of sea level. So how much thinner would it be spread over a ~0.25% larger area?
I guess you’d be able to tell with a barometer, but I’d doubt you’d feel it, especially given the many other climate changes at hand.
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That’s most Americans, isn’t it? I read somewhere that most Americans struggled to find their own state on a map of the US, many couldn’t identify the US on a map of the world.
Having said that, with most states in that big, flat area in the middle where tornadoes breed being large rectangles, it’s little wonder people couldn’t pick out Wyoming from Colorado or New Mexico!
Probably true of many living across most of Russia and northern Asia too.
Thanks for tossing out a stereotype. Care to tell us about “most” other groups of people while you’re at it?
“Most” anything usually isn’t, and people who start off a conversation saying that “most” of a group of people are a certain negative way tend to be distasteful. For further reference, see “bigots”.
I’d be real curious to know where that “somewhere” was that you read that, but even if it was legit, I know of at least one talk show here in the states that has a segment they do (did?) where they walk around outside their studio in New York asking random people basic questions and making fun of them when they get it wrong. They don’t tend to show the people who get the questions right, since that’s not good television.
There are people who don’t know things everywhere. But they are usually things they don’t need to know to get through their daily lives. Like asking a millionaire how much a loaf of bread costs. Doing that could show you how disconnected they are, but the takeaway isn’t usually that they are stupid. They don’t need to know it. They need to know other things.
As for what you read, what was the sample size and how were they selected? If they polled 100 people from a single area, and 51 couldn’t do those things, then they can conclude most of that specific group of people couldn’t. But to extrapolate that out to the entire population of 328,000,000+ Americans is disingenuous at best. Fitting an agenda at worst.
Speaking for myself, I can find my state (one of the rectangles you mentioned) and country on maps, but geography and I have never been friends. I also don’t like to travel. I know where my limits are, and I’m okay with them because I don’t need that knowledge in my day-to-day life.
Back to Waterworld:
Take two people, one who knows geography, and one who doesn’t.
Flood the world so that only the tops of the Tibetan plateau remains above the water.
Drop them in random spots on the now flooded world at least 1000-3000 miles from the last remaining land.
See how well either one does at finding it without any visible landmarks other than water on all sides and astrological bodies (provided they could be seen).
If the one who knows geography also happens to know how to navigate by the stars, he’s set. Provided he has enough food and water to make the trip. If he doesn’t know how to use the stars to navigate, then unless he’s lucky, I would expect him to be just as screwed.
Yes. Funnily enough, the reflexive response of most physical scientists to this question would be “hmm, well let’s assume the Earth is flat” (which makes the answer immediately apparent).
The change in the Earth’s surface area is marginally trickier. It always helps to be aware of the line-square-cube ratio: if you multiply a thing’s linear dimensions by X, then its surface area is multiplied by X2 and its volume is multiplied by X3. So if the Earth’s diameter is multiplied by 1.0012, the area covered by the atmosphere is multiplied by 1.0024, and for its volume to remain the same, then its “height” (and pressure at sea level) must be divided by 1.0024, meaning it decreases by 120 pascals (1.2 millibars).
That change is small enough that if you were going to care about it, then you’d also have to think about the change to the atmosphere’s composition. A water-covered planet would have a considerably lower surface albedo, meaning it absorbs more sunlight, so it is warmer; that doesn’t affect the pressure, but it means there’d be more water vapor in the atmosphere (which means more clouds, which reflect more sunlight into space, so it would be hard to predict where the equilibrium would end up). A m**ster atmosphere is denser and therefore has higher pressure as a function of depth. So it’s conceivable the pressure in the Himalayas would be a little higher than it now is at sea level.
The net gravitational force acting on the atmosphere would also be smaller, meaning lower pressure, but that’d be a really tiny effect.
It goes without saying that we’re ignoring a bunch of other stuff. The levels of oxygen and CO2 would change – maybe a lot – and what with water vapor being a greenhouse gas, Earth might even go full Venus. But the rule is that if you can’t disprove a sci-fi scenario on the back of an envelope, you are obliged to suspend disbelief.
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SEE ALSO: Those freakishly posh and wasteful suburbs-in-space paintings from the '70s, in the context of real-world white flight from urban centers during the same period
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Aye! No one gets away with that on this forum 
I love both as well. Not even shameful about it.
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