Leading research groups have joined the UN to warn of ‘overinvestment’ in fossil fuels.

The authorities say the oil, gas and coal output already planned or in the pipeline will erode efforts to cap global warming.

The world is producing 50 per cent more fossil fuel than can be burned without increasing Earth’s temperature by more than 2 degrees Celsius above preindustrial levels, they said in the global Production Gap Report.

The world is producing or plans to produce more than double what could be tolerated if temperature rise is to be limited to 1.5℃.

“We show for the first time just how big the disconnect is between Paris temperature goals and countries' plans and policies for coal, oil and gas production,” said lead author Michael Lazarus, director of the Stockholm Environment Institute's US Centre.

The ‘production gap’ is the difference between output in the pipeline and the Paris climate goals.

The gap is largest for coal, with countries planning to produce 150 per cent more by 2030 than would be consistent with a 2℃ world, and 280 per cent more than could be burned while limiting warming to 1.5℃.

China alone accounted for more than 40 per cent of global coal output in 2017, after doubling its domestic production from 2000 to 2013.

Nations are on track to produce a 40 to 50 per cent oil and gas surplus in 2040.

“Governments' continued support for coal, oil and gas extraction is a big part of the problem,” said Mans Nilsson, one of 50 co-authors and executive director of the Stockholm Environment Institute.

“We're in a deep hole, and we need to stop digging.”

The report suggests the ‘production gap’ could be narrowed by reducing direct handouts to oil, gas and coal production.

It also suggested major oil firms limit exploration and extraction, and move into other forms of energy.