It's a warm world these days.

The Earth is going through an extraordinary process.... the planet is warming, the ice is melting, and the climate is changing. 





This graph shows show world temperatures have changed over the last 100 years.

The red lines show the overall rising trend in temperatures, but there are short-term 'wiggles' as well - the most significant is a green wave pattern.

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What is the worst-case scenario for climate change? The geological record shows that when the atmosphere suddenly changes, there are big effects on living things. Five major  mass extinction  events are recorded in the rock record of the last 600 million years. The biggest extinction was at the end of the  Permian , around 252 million years ago. It is called the  End-Permian mass extinction. Only about 8% of species survived to live on in the Triassic Period. This photo shows geologists investigating tilted sedimentary rocks at Shangsi in South China. Triassic rocks (at the top right) lie over the older Permian rocks. Each mass extinction in the rocks matches with a change in the chemistry of the rocks called a ' carbon excursion '. Some of the carbon excursions are 'negative CEs' and some are 'positive CEs'. Negative CEs  indicate that lots of gaseous carbon compounds escaped into the air, causing warming. These are sometime
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Climate Change - The Greenhouse Effect

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Climate Change - Coal and carbon dioxide

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