A climate feedback loop (or only climate feedback) is a mechanism through which a change in one part of the climate system (e.g. an increase in global average temperature) causes an effect that further amplifies or reduces the original change.
There are different types of climate feedbacks, but in general, they can be distinguished as positive feedback and negative feedback. A positive feedback amplifies the original change, while a negative feedback reduces or attenuates it.
An example of a positive climate feedback is the reduction of sea ice surface in the Arctic, which causes a decrease in the region’s albedo (i.e. its ability to reflect solar radiation) and thus an increase in heat absorption by the ocean, which in turn causes further melting of sea ice. This feedback loop amplifies the initial climate change.
An example of a negative climate feedback is the increase in ocean temperature, which increases evaporation and thus cloud formation. Clouds reflect solar radiation and reduce the amount of heat absorbed by the Earth, thereby reducing the temperature. This feedback loop attenuates the initial climate change.