[kqr]

We're nowhere near "extreme" levels of noise yet, thankfully. Extreme levels of noise will – just like audio noise – cancel out any signal you're trying to emit. That's a real problem because everything communicates by radio these days.

But even though we're nowhere near extreme levels, this still causes problems in some areas of the world. I don't remember the specifics, but some train-related communications system where I live uses a part of the spectrum that's apparently very busy. This means the train drivers often have to rely on the civilian cell phone system to communicate, which in an emergency will be absolutely swamped and really hard to use.