What is a climate feedback?
This happens when a change in our climate causes an impact which changes our climate further — a knock-on effect which feeds back into our climate. There can be both negative and positive feedbacks:
* Negative feedback — this is an impact which offsets the prevailing change in climate. Under global warming, this would create a cooling effect, balancing out the changes. If the climate was getting colder, it would create a heating effect.
* Positive feedback — this is an impact which increases the change in the climate. It would add to global warming by creating further heating or, if our climate was cooling, would cool the climate further.
http://www.metoffice.gov.uk/climatechange/science/explained/feedbacks.html
