Before revision: Definitions According to the Committee on Abrupt Climate Change of the National Research Council:There are essentially two definitions of abrupt climate change : In terms of physics, it is a transition of the climate system into a different mode on a time scale that is faster than the responsible forcing.
After revision: Definitions Abrupt climate change can be defined in terms of physics or in terms of impacts: " In terms of physics, it is a transition of the climate system into a different mode on a time scale that is faster than the responsible forcing.