Global temperatures may rise 6 degree by 2100: study

The world is destined for dangerous climate change this century and it will now be almost impossible to keep the increase in global average temperatures within the 2 degree Celsius target up to 2100, the report said.

An analysis of how fast the major world economies are reducing their emissions of carbon dioxide from fossil fuels suggests that it may already be too late to stay within the 2C target of the UN's Intergovernmental Panel on Climate Change, the report found.

In order to keep the temperatures within the 2 degree Celsius target, which scientists believe might avert dangerous and unpredictable climate change, the global economy would have to reach a "decarbonisation" rate of at least 5.1 per cent a year for the next 39 years, the report said.

This has not happened since records began at the end of the World War II, according to Leo Johnson, a PricewaterhouseCoopers (PwC) partner in sustainability and climate change.

"Even doubling our current rate of decarbonisation would still lead to emissions consistent with 6C of warming by the end of the century. To give ourselves a more than 50 per cent chance of avoiding 2C will require a sixfold improvement in our rate of decarbonisation," the Independent quoted Johnson as saying.

"It's time to plan for a warmer world... We have passed a critical threshold," he said.

"This isn't shock tactics, it's simple maths. We're heading into uncharted territory for the scale of transformation and technical innovations required. Whatever the scenario, or response, business as usual is not an option," Johnson was quoted by the paper.