109
votes
How much damage to the US would a Yellowstone eruption cause?
EDIT: damn, this got me my first gold badge
Here is a useful source, which is itself based off of this. Here is an ancillary source.
WTL;DR: all the damage
TL;DR:
everything within 80 kilometers ...
- 11.3k
66
votes
How to completely destroy a city, without leaving clues for humanity 4,000 years later?
Rock and clay don't burn well, leaving you with a lot of dressed stone lying around to say there was once a city here.
Fire from above implies volcanoes, as we learned from Pompeii, that's actually a ...
- 116k
65
votes
Could a natural disaster completely isolate a large city in the modern world without destroying it?
Totally possible. 2 million Australian's came very close in "20 bloody 20"
About 80% of your requirements were met in 2020. 12 days of total isolation is a little shy of your requirements. A ...
- 44.1k
53
votes
How to completely destroy a city, without leaving clues for humanity 4,000 years later?
How about a catastrophic flood?
Have the city built on a large river. A landslide further up blocks the river and causes an enormous lake to form (also cutting off water supply to the city causing ...
- 76.9k
52
votes
What would be the effect(s) of this asteroid?
Everything Dies
The combination of mass and velocity is inescapable. The follow-on asteroids don't matter. The initial impact will do the trick.
Half the mass of the moon is approximately 36 ...
- 29.5k
48
votes
Accepted
What would make the internet go away?
A really big solar flare could do it.
Something on a similar or greater scale to the Carrington Event back in the 1800s. Getting hit with a flare that large, or larger would damage or destroy ...
- 16.8k
46
votes
Accepted
How to completely destroy a city, without leaving clues for humanity 4,000 years later?
I have much academic experience with some of this, especially the second part of your question. I'll address a few different sides of things.
The most drastic way I can think of that could ...
- 2,336
35
votes
How to completely destroy a city, without leaving clues for humanity 4,000 years later?
Moved from comment to answer because I've done more research.
Try the biblical account of Sodom and Gomorrah, believed to be near the coast of the Dead Sea . The cities were destroyed by means of ...
- 9,732
35
votes
Accepted
What could explain why trees only have 12 rings?
Every fourteen thirteen years, vast swarms of a locust-like creature emerge from underground, where they have been living in the larval stage for all this time. The swarm darkens the sky, and eats ...
- 2,349
29
votes
Accepted
What would be the effect(s) of this asteroid?
Earth is gone. The Moon is gone. Mars gets nuked. The entire Solar System becomes hotter than Mercury for a couple days. The Sun will appear to glow up to 12,000 times brighter. The Solar System will ...
- 2,151
27
votes
Accepted
How to transport 10,000 terrestrial trolls across ocean fast?
Frame challenge
You say the trolls can't float. However ...
Average human mass - 50 kg
Average human height - 173 cm
Average troll mass - 90,700 kg
Average troll height - 30 m
By the square cube ...
- 49.3k
26
votes
What would make the internet go away?
Let's start by addressing the "leave as much other technology intact as possible" part first:
10 years ago, you could have taken down the internet and most things would have continued to function ...
- 87k
25
votes
How can water magic destroy the world?
If she can “control all water that already exists,” I assume that phase changes are allowed. In this case, you have two very cool options that are almost certain to kill all life on Earth very quickly:...
- 3,321
24
votes
A few dozen Millennia after Yellowstone erupts, how close would a parking lot look to a natural Iron Vein?
Never
For one thing, to my knowledge, no veins of Iron have ever been found in volcanic breccia so large deposits of steel (iron) found in one would immediately be suspicious. Additionally, cars are ...
- 6,706
24
votes
How to completely destroy a city, without leaving clues for humanity 4,000 years later?
Scale it up - you thought "a meteor strike is too visible". Good! If your impact crater is deep enough, people are going to think "valley", not "crater".
Hit them with 3-or-more meteors in a row, ...
- 15.2k
24
votes
Would human intelligence evolve if humans had access to infinite food?
Fast reproducing organisms would have a major advantage
In biology there's an idea called r/k selection. Some organisms optimize for fast cheap reproduction, some for high quality reproduction. High ...
- 37.2k
23
votes
When dealing with a drought or a bushfire, is a million tons of water overkill?
dosis sola facit venenum applies also to this case, I think.
There is so much water that soil can absorb in a given span of time, anything more than that will simply flow, and with flow comes erosion.
...
- 272k
22
votes
Could a natural disaster completely isolate a large city in the modern world without destroying it?
The 2010 eruption of Eyjafjallajökull is an example.
The 2010 eruptions of Eyjafjallajökull were a period of volcanic events at Eyjafjallajökull in Iceland which, although relatively small for ...
- 272k
21
votes
When dealing with a drought or a bushfire, is a million tons of water overkill?
A gigaliter is 1 million cubic meters. So that much water will cover a square kilometer of land to a one-meter depth.
Dumping that much of water in ten minutes would be less "firefighting" ...
- 8,310
21
votes
Accepted
Why is English the only language spoken?
I'll insist on the Horizon: Zero Dawn scenario.
TL;DR: humanity gets wiped out, no survivors. After the disaster passes, new humans are grown in artificial wombs and the 1st generation is educated by ...
- 134k
20
votes
The moon will fall to earth in 100 years, how fast is the asteroid that knocked it down?
TL;DR: What you want is impossible for multiple reasons.
Lets be honest: what you want is clearly impossible. In order to have a slowly decaying orbit, you need to have either a repeatedly applied or ...
- 69.6k
20
votes
How can water magic destroy the world?
"or bacteria"
Well, that is the difficulty. Everything else can be done by having the oceans rise and roll all over the sea - this, by the way, happens in Agatha Christie's The Hound of ...
- 54.6k
19
votes
What would be the effect(s) of this asteroid?
5% of lightspeed is insanely fast for an asteroid.
Earth is gone. It doesn't matter where that giant asteroid hits.
Luna is gone.
Some of the combined mass might form a new belt, but much will be &...
- 110k
19
votes
How can water magic destroy the world?
The only easy way to kill bacteria with water is heat. Which leaves the question: How does a godess heat the water without being a godess of heat?
The answer is simple: By supplying the necessary ...
16
votes
How to completely destroy a city, without leaving clues for humanity 4,000 years later?
It doesn't necessarily have to be a natural disaster in the traditional sense. It could be that a natural/weaponised biological plague tore through the population making them go completely mad. They ...
- 12.9k
16
votes
Could a natural disaster completely isolate a large city in the modern world without destroying it?
Occupation
https://en.wikipedia.org/wiki/Mosul#Government_by_the_Islamic_State_of_Iraq_and_the_Levant_(ISIL)
Mosul was a city with a population of over 1 million. It was captured by ISIS militants ...
- 304k
15
votes
A few dozen Millennia after Yellowstone erupts, how close would a parking lot look to a natural Iron Vein?
No, it will never happen that cars buried in the ground will revert to iron ore.
The scenario you described already happened, on a smaller scale, in Pompei. Tool used by the people, even bread, ...
- 272k
15
votes
What would be the effect(s) of this asteroid?
Let me provide an alternative for jdunlop's amazing answer.
I will build up from that answer, assuming that Earth is completely disassembled. The change is that we won't have an asteroid belt.
I ...
- 134k
14
votes
What could explain why trees only have 12 rings?
The issue of having no living trees older than 12 years would at best indicate that some event occurred 12 years ago resulting in complete devastation of the forest in that region (note that an ...
- 141
14
votes
What would make the internet go away?
Political events, not technological. Populist-nationalism continues to rise and spread worldwide, and “anti-internet” sentiment becomes popular among nationalists. (The open internet is, of course, ...
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