# How would X-Seed 4000(s) affect the weather?

So, the X-Seed 4000 (https://en.wikipedia.org/wiki/X-Seed_4000) is a rather large lad. The tallest building ever fully realized. Let's just say that, in five decades, they decide to actually build this thing - not on the coast of Tokyo, mind you, but somewhere a little less... active, like, in the Russian steppe or in the middle of Kansas.

According to the specs, it looks like this bad boy is going to be 4,000 meters tall and roughly cone-shaped. That means it's quite a bit of a sky-piercer and has a pretty sizable footprint.

What I'm concerned about is the weather. Not inside - after all, by this time in the future, we'll probably be able to keep it nice in cozy on the inside using our technology. I'm talking about the outside.

How exactly would this affect the weather around it? Would it cause tornadoes by blocking wind? Would it throw off the jetstreams? What sort of consequences would we need to be aware of?

(Y'know, so we could maybe make lots and lots of these and eventually replace cities. After all, if you've got 8,000 of these, you could probably house 8 billion people. So there will definitely be more than one.)

• "Replace cities" for what purpose? Cities are not warehouses of people, they are actual functional structures. We don't build cities to stuff people in them, we build cities for trade, industry, services and so on. All these activities are much easier to perform if the city is not a mountain... Jan 4, 2020 at 10:59

Like a mountain

The structure, being 4km high and shaped like a pyramid, would act in much the same way as a mountain.

We have plenty of data to draw from, with numerous mountains of similar height and shape to study. Keep in mind Everest is 8000m above sea level, our new building is half that height.

Common weather patterns include:

• Precipitation to one side of the mountain as air is forced upwards and condenses
• Dry air on the other side as a result
• snow to altitudes above a few hundred meters (dependant on latitude)
• strong wind at higher altitudes, but likely not severe (and likely not tornadoes)

More concerning would be the enormous heat and energy the building will require to maintain air temperature inside. We are talking about enormous amount of air, water and electricity required. The effects of the building would be much more far reaching than it's physical presence.