Global warming firmed up

Climatologists have firmed up their predictions of how much warmer the climate will be over the next 20 to 30 years.

New research by two teams of scientists using different climate models predicts the global mean temperature will be between 0.3 C and 1.3 C warmer by 2020-2030 than in 1990-2000.

Later in the century, if greenhouse gas emissions are at the high end of predictions, they could force up temperatures by 0.3 C to 7 C.