Keep most oil, gas in ground for planet, scientists urge

Sixty percent of the world’s current oil reserves and fossil methane gas and 90 percent of coal should remain in the ground for half the chance of limiting global warming to 1.5 C by 2050, according to a new modeling study.

The authors of the study, “Strict fossil fuel extraction limits needed to meet 1.5 C warming limit”, said the decline in oil and gas production required globally by 2050 implies that many regions face peak production now or during the next decade.

The study, published in the scientific journal Nature on Thursday, said many operational and planned fossil fuel projects are not conducive to meeting internationally agreed climate targets.

“It is estimated that oil and gas production, for example, must decline by 3 percent annually until 2050 to meet these goals. Policies to restrict production and reduce demand will be needed to encourage producers to reassess production,” the study said.

Fossil fuels account for 81 percent of the global energy consumption, but their production and use will need to decline substantially to meet internationally agreed climate goals set out by the Paris Agreement in 2015 to limit global warming to 1.5 C relative to preindustrial times.

In 2015, a Nature paper estimated that a third of oil reserves, half of gas reserves and more than 80 percent of coal reserves should remain unused by 2050 to have a good chance of capping global warming at 2 C.

The new study concluded that a large increase in unextractable fossil fuel reserves will be required, particularly for oil of which an additional 25 percent of reserves must stay in the ground as compared with the 2015 estimates.

The authors of the new study suggested that these results may be an underestimate as their model does not consider future Earth system feedbacks, given the uncertainties around the rate of deployment and scale of technologies needed to counteract emissions.

Commenting on the study, Frank Jotzo, professor at the Australian National University’s Crawford School of Public Policy, said humanity is not running out of coal, oil or gas, but instead running out of options for the waste product carbon dioxide.

“This study is a reminder of just how little room there is for the continued use of fossil fuels, if the world is to succeed in limiting global warming to levels that might be safe. This is not a new insight, with shrinking carbon budgets having been computed for many years,” Jotzo said.

Energy transition

Rebecca Colvin, a senior lecturer from ANU’s Crawford School of Public Policy, said the global transition of the energy system from fossil fuels to low- or no-emissions sources will have significant effect on the regional communities with economies buoyed by the fossil fuel sector.

She said the study highlights the need for an “open and honest discussion” in Australia about equipping those regions which are dependent on fossil fuels for the “global energy transition”.

John Quiggin, an economics professor at the University of Queensland, said: “We need to replace them (coal, Methane gas) with clean carbon-free energy sources including solar, wind, and hydroelectricity.”

Matthew England, climate scientist and professor at the University of New South Wales, said: “The results of this study are unambiguous — ongoing fossil fuel extraction and burning will deny us any chance of a safe climate future.”