Hotter days are coming for the nations of the world as a leading Australian climate scientist predicted global temperatures will rise to 4C-6C by 2100. The culprit? Global carbon emissions have grown three times faster compared with a century ago.

A study warning of the growth of emissions revealed that global emissions from fossil fuels, by the end of 2012 alone, would reach the record level of 36 billion tonnes.

"Just to put this into perspective, this is 58 per cent over 1990 . . . and growing about three times faster than they were growing during the 1990s," Dr Pep Canadell, one of the lead authors, told ABC radio.

"In 2012 we grew about 2.6 per cent and last year was about three per cent."

As expected, much of the spike in the global emission growth came from China, the world's recognised largest carbon emitter, at 80 per cent. The rest of the 20 per cent was divided among emerging economies and the developed world, including Australia.

"If you look at what's has happened over the last year and this year and what has happened overall over the last 10 years, we are now following perfectly on track of the emissions path that is going to take us to anywhere between four and six degrees by 2100 if we don't do anything different from what we are doing now," he said.

If for any consolation, there could still be possibly enough remedies to combat the growing spike of global carbon emissions if the federal governments of the world take decisive and aggressive measures.

Dr Canadell mentioned the countries of France and UK as examples. France decisively moved to utilise nuclear power generation, while the UK shifted to gas from coal for power production which contributed significant reductions to the world's global emissions figures.

"We have no idea whether we can actually take these examples and put them into a global context for many decades but there is certainly good past experience which could allow for governments to be inspired and look at much more aggressive and faster actions," he said.