Climate

At This Rate, The World Will Have To Cease All Carbon Emissions In 2040 To Stay Under 2°C

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By 2040, the world will emit all the carbon it can afford while remaining within safe ranges of climate change, according to a report released last week.

Scientists and policymakers have generally settled on 2°C as the amount of global temperature increase, over pre-industrial levels, the climate can take without creating truly dangerous upheavals. Because the effect of carbon in the atmosphere is cumulative, staying below that threshold requires a hard limit on the amount of carbon the world emits between now and 2100. We’ve already blown through a bit over half of that “carbon budget.” Last week’s World Energy Outlook 2014 from the International Energy Agency (IEA) projects that, on our current course, we’ll chew through the rest by 2040.

To remain under 2°C, all world carbon emissions would have to immediately drop to zero after that year, which of course they won’t. While IEA projects that renewables will grow aggressively between now and 2040, overtaking coal as the globe’s leading source of electricity, and that coal and oil use will effectively plateau by that point, fossil fuel use — and thus carbon emissions — will remain about 75 percent of the world’s energy consumption. That, according to IEA, puts us on course for roughly 3.6°C of global warming by 2100.

“By 2040, world energy supply is divided into four almost equal parts: low-carbon sources (nuclear and renewables), oil, natural gas and coal,” according to the IEA report’s press release. “In the central scenario, the entire carbon budget allowed under a 2°C climate trajectory is consumed by 2040, highlighting the need for a comprehensive and ambitious agreement at the COP21 meeting in Paris in 2015.”

The Paris meeting will mark the next round of international climate talks, where observers hope a series of binding treaties to significantly cut carbon emissions will be hammered out by the major world powers. The previous round of such talks in 2009 failed to secure any sort of agreement. If the world’s available 2°C carbon budget is to be stretched beyond 2040, the 2015 talks will need to significantly increase the rate at which countries — particularly the U.S., China, and Europe — are cutting their emissions. IEA also projects that the world will need to ramp up its investments in low-carbon energy to four times above their current levels. This would require bringing annual global investment up to roughly $1 trillion, from the roughly $230 billion IEA anticipates it will stay at through 2020 given current policies.

Back in September, a coalition of 340 global investors representing $24 trillion in assets released a statement calling on national governments to institute meaningful and reliable carbon pricing policies in order to drive more investment into clean power.

IEA’s numbers also roughly line up with the latest report from the Intergovernmental Panel on Climate Change (IPCC), which determined that, on its current course, the world will lose out on a 50 percent chance of staying under 2°C in 28.4 years, and will lose out on a 33 percent chance of doing so within 33.3 years.

The IEA report anticipates that demand for coal in the United States and Europe will drop between now and 2040, and will plateau or even drop slightly as well for China, while increasing slightly for the world as a whole. It also projects that annual demand for all forms of energy combined will flatline almost immediately for advanced western nations, and will effectively flatline for China as well by 2040, while roughly doubling for the rest of the world over that time period.

Another factor that came to light too recently for IEA to build it into its projections is the pledge the United States and China announced last week, which commits the U.S. to cutting its carbon emissions at least 26 percent below 2005 levels by 2025, and commits China to peaking its emission by 2030 and getting 20 percent of its energy from renewables by that same year. The details have yet to be worked out, and most observers agree the primary significance of the deal is political, as a coalition building tool in the run-up to the 2015 summit. On its own, experts say the deal would likely alter global temperature increases by 0.1°C if fully carried out.