Four degrees of warming would be hotter than any time in the last 30 million years, and it could happen as soon as 2060 to 2070
By Stephen Leahy
The prospect of a four-degree Celsius rise in global average temperatures in 50 years is alarming – but not alarmist, climate scientists now believe.
Eighteen months ago, no one dared imagine humanity pushing the climate beyond an additional two degrees C of heating, but rising carbon emissions and inability to agree on cuts has meant science must now consider the previously unthinkable.
“Two degrees C is already gone as a target,” said Chris West of the University of Oxford’s UK Climate Impacts Programme.
“Four degrees C is definitely possible…This is the biggest challenge in our history,” West told participants at the “4 Degrees and Beyond, International Climate Science Conference” at the University of Oxford last week.
A four-degree C overall increase means a world where temperatures will be two degrees warmer in some places, 12 degrees and more in others, making them uninhabitable.