An Irish climate change academic has warned of "runaway warming" if global temperature increases are not maintained below 2C.

His remarks are in response to an essay published in 'Proceedings of the National Academy of Sciences'.

It warned that a combination of melting ice, warming seas, shifting currents and dying forests could tilt the Earth into a "hothouse" state.

The authors say that human efforts to reduce emissions will be increasingly futile.

Senior Fellow for Climate and Energy Policy at the Institute of International and European Affairs Joseph Curtin said the conventional wisdom is that if we can maintain increases in global average temperatures well below 2C then humanity can operate safely.

This is the intention of the international community set out in the Paris Climate Agreement in 2015.

Speaking on RTÉ's Morning Ireland, Mr Curtin said this report by scientists at the Potsdam Institute for Climate Impact Research is suggesting that even the 2C threshold could unleash planetary forces that are difficult to understand or control.

If the tipping points described in the report kick in, he said we could enter what is described as runaway warming.

Scientists have always been concerned about these tipping points, said Mr Curtin, who is also a member of the Climate Change Advisory Council.

This report is the latest in a long line of reports suggesting these tipping points could be triggered but what they are suggesting is that even at 2C we are not necessarily at a safe threshold.

Mr Curtin said it does not really change the imperative that we need to manage the situation we are in; we need to dramatically reduce greenhouse gas emissions as soon as possible.

Mr Curtin said we can sometimes forget that we in Ireland do have the power to do something about this and we can be a leading light and an example in this area, but our experience to date has not been particularly encouraging.

Increasing the level of carbon tax in the upcoming Budget, Mr Curtin said, was potentially a very important development in terms of Ireland’s journey in doing something about the issue.

Mr Curtin said we have always been aware of what is known as the "time-lag effect" and have already increased the global temperatures by 1C above pre-industrial level through human intervention but the greenhouse gases that are already in the atmosphere means that more increases are in the pipeline no matter what we do.

He said we are producing record levels of greenhouse gases every year and we know the global economy cannot be switched off overnight, we know with absolute certainty that for the next couple of decades it will be more greenhouse gas emissions added to the atmosphere.

These two factors combined with the tipping points, means that we will have increases in temperatures in the years and decades ahead, he said.