Keeping the global thermostat from being jacked up into the red zone will mean putting most of its coal, half its natural gas, and much of its oil reserves off limits, British researchers reported Wednesday.
More than 80 percent of all world's coal reserves "need to be classified as unburnable" to keep worldwide average temperatures from topping two degrees Celsius (3.6 Fahrenheit) above pre-Industrial Age levels, said Christope McGlade, the lead author of a new study from University College London (UCL).
McGlade's study examined how much of the world's fossil fuels will have to remain untouched in order to keep the world from blowing through its "carbon budget" — how much fossil fuel can be burned before pushing the climate beyond the two-degree limit the United Nations has set as a global target. To keep from overshooting that mark, McGlade said during a press conference, the world would have to give up 223 billion barrels of oil and 290 billion metric tons of coal by 2050.
By comparison, the world currently burns about 87 million barrels of oil a day and more than eight billion tons of coal a year, according to US Energy Information Administration statistics.
Balancing the carbon budget will require the near-total decarbonization of electricity production by 2030, McGlade said. Nuclear power "plays a very important part" in that assumption, as do technologies such as biofuels and still-developing efforts to capture and store power plant emissions like carbon dioxide, he said.
'There's absolutely huge coal reserves in China, Russia, and the United States and the overwhelming majority of these shouldn't be used.'
Natural gas is far cheaper and more abundant than just a decade ago thanks to the increased use of hydraulic fracturing technology. It's also much cleaner than coal and it's been replacing coal in many US power plants for years.
"Gas plays a very important role in the global environmental system in displacing coal, particularly in the electrical and industrial sectors," McGlade said. But even with those advantages, he said half of the world's natural gas will have to remain untouched to limit warming to two degrees.
The study concludes that societies need a "stark transformation" of their attitudes toward natural resources, which typically have been aimed at preventing shortages. Currently, oil companies spend about $670 billion on exploration, said Paul Ekins, the head of UCL's Institute for Sustainable Resources.
"One might ask whey they're doing this when there's more in the ground than we can afford to burn and that money might be better spent," Ekins said. "The investors in those companies might think it's better spent either developing low-carbon energy sources or, indeed, being returned to investors as dividends."
The study was funded by the government- and industry-backed United Kingdom Energy Research Center and published Wednesday in the journal Nature. It used economic calculations to show which regions will have to walk away from their natural resource deposits — and many of them are among the world's biggest, wealthiest countries.
Basically, the higher the cost of extraction, the better it would be to leave it alone, the researchers concluded.
"For example, there's absolutely huge coal reserves in China, Russia, and the United States and the overwhelming majority of these shouldn't be used," McGlade said.
The Arctic, where natural hazards and recent crude prices have cooled dreams of tapping into that that region, would have to remain untouched, McGlade said. Meanwhile, the Middle East could walk away from up to 260 billion barrels of oil — a figure comparable to the entirety of Saudi Arabia's estimated reserves.
And Canada's push to develop the Alberta tar sands would require "very rapid decarbonization" of the heat-intensive process used to extract heavy oil, either by using nuclear power, renewable energy, or biomass. "So 85 percent of the reserve base, which we estimate at about 50 billion barrels, has to remain in the ground," McGlade said.
Scientists and some business leaders have long warned that preventing catastrophic climate change means stepping away from the drills and shovels and turning resources toward developing energy sources that don't emit carbon dioxide and other greenhouse gases. The issue will be front and center in 2015, with scientists expecting to report soon that the world set a new temperature record in 2014 and with diplomates headed to Paris in December in the hopes of hammering out a global framework to address climate change..
Ekins said he hopes the new study "helps them understand what it takes" to get to a deal, if not with two degrees as a target than at most three.
"I think as the impacts of climate change begin to be felt in more and more countries, in increasingly unpleasant ways, it seems to me that the political will to do something about it will increase," Ekins said. "And then I think it's really important that policymakers know how far they've actually got to go if they are to make a meaningful impact on this problem."
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