The Palaeocene–Eocene transition is visible in the landscape of North Dakota. The PETM is present within the Golden Valley Formation which weathers as prominent brightly coloured buttes in west-central North Dakota. Dr Guy Harrington / gees.bham.ac.uk

By Louise Gray, Environment Correspondent
Published: 6:30AM GMT 02 Nov 2010 The Earth will take 100,000 years to recover from global warming if mankind continues to pump greenhouse gases into the atmosphere, geologists have warned. A conference organised by the Geological Society in London this week will bring together scientists from around the world to look at how the world coped with climate change in the past. By studying rock sediments from millions of years ago geologists have been able to model how increases in greenhouse gases led to temperature change and extinction of species. Professor Jim Zachos, of the University of California, said that 55 million years ago volcanic activity caused around 4,500 gigatons of greenhouse gases to be released into the atmosphere over thousands of years. This caused the planet to warm by 6C (10.8F), forcing whole ecosystems, including early mammals, to adapt, migrate or die out in certain areas. Prof Zachos said that if the world continues to pump out greenhouse gases at the current rate, around 5,000 gigatons of greenhouse gases will be released into the atmosphere over a few hundred years. He said this will cause a more rapid temperature rise that at any other time in history and could cause “mass extinction of species”. “The impacts will be pretty severe compared to 55 million years ago in terms of evolution of this planet,” he said. …

Earth will take 100,000 years to recover from global warming say geologists