Guardian: What is the significance of the Paris climate talks?
In 30 years, carbon dioxide levels in the atmosphere will have risen to such an extent that temperatures will be 2C higher than in pre-industrial times, scientists say. Beyond that temperature, there will be devastating environmental consequences: worsening storms, extreme heat waves and rising seas. The most important decision to be taken in Paris will therefore be to agree, through a binding commitment, that 2C is the highest acceptable limit...