How is nuclear winter created?

Answer:
  1. Large numbers of high yield nuclear weapons are detonated.
  2. This ignites enormous firestorms in many forests.
  3. Soot from these firestorms rises into Stratosphere, where it stays for months to years, blocking out sunlight all over the world.
  4. Without sunlight the earth cools dramatically.
  5. Result: a winter that might last many years before temperatures rise again.
First answer by Eccles-Jordan Trigger. Last edit by Eccles-Jordan Trigger. Contributor trust: 127 [recommend contributor recommended]. Question popularity: 17 [recommend question].