Global warming must be limited to 2°C, scientists say

The United Nations' negotiations on climate change reopened in Montreal, Canada, this week, against a backdrop of warnings from climatologists about the consequences of rising concentrations of “greenhouse” gases in the atmosphere.

Russia's ratification of the Kyoto protocol triggered the protocol's coming into force earlier this year, but the agreement will only slightly reduce the steepness of the rising curve of concentrations of gases and even then only if countries implement it.

Although the scientists and most countries are clear that the Kyoto protocol, agreed in 1997, is only a first …