The world climate conference in Copenhagen has heard environmental changes are taking place more rapidly than previously forecast.

Temperatures, sea levels, ice sheets, oceans and extreme weather events were reported to be already moving "beyond the patterns of natural variability".

The Met Office believes it will only take small rises in temperature to destroy large swathes of rainforests around the world.

Meanwhile, the Prince of Wales gave a speech in Brazil, where he announced we are "at a defining moment in the world's history" in action against climate change.

He was speaking to 200 business leaders in Rio de Janeiro, where he and the Duchess of Cornwall stopped off during a tour of South America.

The Prince will also meet Amazon community leaders to discuss some of the critical issues facing the Brazilian rainforest.

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