Oxford: Developed oil, gas and coal reserves, if exhausted, are enough to push Earth well past the threshold for dangerous climate change, according to a report published Thursday.
Fossil fuels from active fields and mines allowed to operate through their projected lifetimes would punch through the two degree Celsius cap for global warming laid down in the Paris Agreement, said the report, based on industry data.
The analysis by Oil Change International was released the day after world leaders gathered in New York to speed the global climate pact, signed by 195 nations in December, into force.
That is likely to happen before the end of the year, UN Secretary-General Ban Ki-moon said Thursday.
As climate change impacts -- heat waves, deadly flooding, storm surges fuelled by rising seas -- hit earlier and harder than predicted, pressure has grown to accelerate the transition away from carbon-intensive fossil fuels.
The coal industry has been hit hardest, with moratoriums on new plants put in place this year in China and Indonesia, along with one covering federal land in the United States.
The Paris Agreement calls for holding global warming at "well below" two degrees Celsius (3.6 degrees Fahrenheit) compared to pre-Industrial Revolution levels, and under 1.5 C (2.7 F) if possible.
Existing reserves of oil and gas alone, even without coal, would be enough to breach the 1.5 C barrier, according to the 60-page report.
"If the world is serious about achieving the goals agreed in Paris, governments have to stop the expansion of the fossil fuel industry," said Stephen Kretzmann, executive director of Oil Change International.
Many of 200 climate scientists gathered in Oxford, England this week at a conference on the more stringent climate change goal have said that staying under 1.5 C may be out of reach.
The planet has already heated up 1.0 C (1.8 F), and could see its first year above 1.5 C "within a decade," said Richard Betts, head of climate impacts research at the Met Office Hadley Centre in England.
The new analysis compares the projected emissions of burning fossil fuels from current operations to the carbon "budget" -- the sum total of CO2 that can be emitted without exceeding the 2C limit.
Scientists calculate that budget to be less than 1,000 billion tonnes of CO2.
Previous studies of these limits have focused more on the consumption of oil, gas and coal rather than the potential for supply.
"Once an extraction operation is underway, it creates an incentive to continue so as to recoup investment and create profits," Greg Muttitt, lead author of the report, said.
This is how carbon emissions get "locked in", he added.
Projected investment in new fields, mines and transportation infrastructure over the next 20 years is $14 trillion (12.5 trillion euros), according to industry figures.
Some of the biggest projects in the pipeline are in the United States, Canada, Australia, India, Russia, Qatar and Iran.
For coal -- the dirtiest, or most carbon-polluting, of the major fossil fuels -- two countries, Australia and India, are moving forward with large-scale new mining development.