- The vast majority of the world's known fossil fuel reserves must be kept in the ground to have even a 50% chance of keeping global temperatures from rising 1.5 degrees Celsius above pre-industrial levels.
- The study estimated that oil and gas production must decline worldwide by 3% each year through to 2050, implying that most regions must reach peak production now or during the next decade.
- The findings reaffirm the yawning gap between meaningful climate action and the rhetoric of policymakers and business leaders touting their commitment to a so-called "energy transition."
LONDON — The vast majority of the world's known fossil fuel reserves must be kept in the ground to have some hope of preventing the worst effects of the climate emergency, according to new research.
The peer-reviewed study, published in the scientific journal Nature on Wednesday, found that 90% of coal must remain unextracted and nearly 60% of oil and fossil methane gas must stay underground to have even a 50% chance of keeping global temperatures from rising 1.5 degrees Celsius above pre-industrial levels.
This temperature threshold is the lower target of the landmark 2015 Paris Agreement, an accord widely recognized as critically important to avoid an irreversible climate crisis. The 1.5 degrees Celsius level is particularly crucial because beyond this internationally agreed goal, so-called tipping points become more likely.
The study estimated that oil and gas production must decline worldwide by 3% each year through to 2050, implying that most regions must reach peak production now or during the next decade.
Countries that are heavily reliant on oil and gas for state revenues, such as OPEC members Saudi Arabia, Iraq and Kuwait, are thought to be at particularly high risk unless they rapidly diversify their economies.
The researchers, led by environmental and energy economist Dan Welsby at University College London, noted the "bleak" forecasts were likely to be somewhat conservative given that a greater than 50% chance of limiting warming to 1.5 degrees would require more carbon to remain untapped, and because of uncertainties around the timely development of scalable negative carbon emission technologies.
The analysis notes that the need to keep global fossil fuel reserves in the ground varies across countries. This is based on the regional differences of limits to fossil fuel extraction and on the carbon intensity and cost of energy resources worldwide. For instance, highly polluting reserves, such as Canada's tar sands and Venezuelan oil, are left in the ground in this model.
Authors of the study built on the findings of research published in 2015 assessing how much of the world's fossil fuel reserves must remain unused to limit global heating to 2 degrees Celsius. The research has now been updated to examine what's necessary to limit warming to 1.5 degrees Celsius.
For instance, the U.S., Russia and former Soviet states have half of global coal reserves but will need to keep 97% underground, according to the study. For Australia, this figure comes in at 95%, while China and India must leave 76% of their coal reserves in the ground, the study says.
Meanwhile, 84% of Canada's oil sand reserves would need to remain unexploited and nearly two-thirds of Middle Eastern states' oil and gas reserves must not be extracted. Europe would need to leave 72% of its oil reserves and 43% of its gas reserves underground, while Africa would need to walk away from roughly half of its oil and gas reserves, according to the research.
To keep global heating below 1.5 degrees Celsius, the modeling also suggests all undeveloped oil and gas resources in the Arctic must be kept in the ground.
The findings reaffirm the yawning gap between meaningful climate action and the rhetoric of policymakers and business leaders touting their commitment to a so-called "energy transition."
Burning fossil fuels is the chief driver of the climate crisis, yet the world's dependency on fossil fuels is set to get even worse in the coming decades. As a result, world leaders are under immense pressure to deliver on promises made as part of the Paris Agreement ahead of highly anticipated U.N. climate talks due to be held in Glasgow, Scotland in early November.
Last month, the world's leading climate scientists delivered their starkest warning yet about the deepening climate emergency. U.N. Secretary-General António Guterres described the Intergovernmental Panel on Climate Change's Aug. 9 report as a "code red for humanity." He added: "The report must sound a death knell for coal and fossil fuels before they destroy our planet."
Earlier this year, the International Energy Agency said that it sees no need for investment in new fossil fuel developments if the world is to effectively tackle the deepening climate emergency.