Global catastrophic risk

A global catastrophic risk is a hypothetical future event with the potential to seriously damage human well-being on a global scale. Some events could destroy or cripple modern civilization. Any event that could cause human extinction is also known as an existential risk.

Potential global catastrophic risks include but are not limited to hostile artificial intelligence, nanotechnology weapons, climate change, nuclear warfare, and pandemics.

Researchers experience difficulty in studying human extinction directly, since humanity has never been destroyed before. While this does not mean that it will not be in the future, it does make modelling existential risks difficult, due in part to survivorship bias.

Classifications

Global catastrophic vs existential

Philosopher Nick Bostrom classifies risks according to their scope and intensity. He considers risks that are at least "global" in scope and "endurable" in intensity to be global catastrophic risks. Those that are at least "trans-generational" (affecting all future generations) in scope and "terminal" in intensity are classified as existential risks. While a global catastrophic risk may kill the vast majority of life on earth, humanity could still potentially recover. An existential risk, on the other hand, is one that either destroys humanity entirely or prevents any chance of civilization recovering. Bostrom considers existential risks to be far more significant.