What are climate change feedback loops?

This question and answer is part of the Guardian's ultimate climate change FAQo See all questions and answerso Read about the projectIn climate change, a feedback loop is the equivalent of a vicious or virtuous circle - something that accelerates or decelerates a warming trend. A positive feedback accelerates a temperature rise, whereas a negative feedback decelerates it.Scientists are aware of a number of positive feedbacks loops in the climate system. One example is melting ice. Because ice is light-coloured and reflective, a large proportion of the sunlight that hits it is bounced back to space, which limits the amount of warming it causes. But as the world gets hotter, ice melts, revealing the darker-coloured land or water below. The result is that more of the sun's energy is absorbed, leading to more warming, which in turn leads to more ice melting - and so on. Continue reading...