World temperatures are likely to increase more than 2°Celsius this century, advancing past the "tipping point" that a global climate deal aimed to avert, according to scientists. The journal Nature Climate Change published a study, that showed a 90 per cent chance that temperatures will rise this century by 2 to 4.9 degrees Celsius.
According to researchers at the University of Washington, there was only a 5 per cent chance that warming could be at or below 2°Celsius – one of the targets set by the 2015 Paris climate deal on limiting emissions of greenhouse gases that warm the planet.
Failing to hit the target could have dramatic consequences on people's livelihoods – such as prolonged periods of drought and rising sea levels, according to Adrian Raftery, the lead author of the study and a professor at the University of Washington.
The scientists used statistical projections based on total world population, GDP per capita and the amount of carbon emitted for each dollar of economic activity, known as carbon intensity for the study.
"Our analysis shows that the goal of 2 degrees is very much a best-case scenario," said Raftery.
"It is achievable, but only with major, sustained effort on all fronts over the next 80 years."
Dr Dargan Frierson, from the University of Washington, said, "Countries argued for the 1.5°C target because of the severe impacts on their livelihoods that would result from exceeding that threshold. Indeed, damages from heat extremes, drought, extreme weather and sea level rise will be much more severe if 2°C or higher temperature rise is allowed.
"Our results show that an abrupt change of course is needed to achieve these goals."
The study used a different approach from that taken by the Intergovernmental Panel on Climate Change (IPCC) in its recent report.
The IPCC report included future warming rates based on four carbon emission scenarios.