Since the signing of the Paris climate accord in December, have we made any progress in cutting global emissions?
Let’s start with the good news. Emissions in China, the world’s largest producer of carbon dioxide, dropped by around 3 percent in 2015, according to preliminary government statistics, thanks largely to an economic slowdown and a dramatic decrease in the burning of coal. U.S. carbon dioxide emissions from energy consumption (which account for more than 90 percent of total emissions) also fell by nearly 3 percent from 2014 to 2015, according to the U.S. Energy Information Administration. And worldwide, carbon dioxide emissions in 2015 fell by 0.6 percent, according to a study in Nature Climate Change—the first time emissions have shrunk in a period of economic growth, rather than contraction.
And now, the bad news: we still have a long way to go to avoid catastrophic global warming.
A report released today by the International Energy Agency that focuses on urban energy consumption contains some encouraging projections, but a closer look at them reveals that they are wildly optimistic.
The IEA predicts total worldwide energy demand will increase between now and 2050, but with strong government action, that increase can be limited enough to slow global warming to 2 °C or less. Cities account for about two-thirds of global energy demand and 70 percent of total energy-related carbon dioxide emissions, so limiting energy use and emissions from metropolitan areas will be critical to achieving the goals of the Paris agreement. Limiting urban energy use to an increase of 20 percent (compared to a 70 percent increase that would happen if current trends continue) would be a huge factor in staying below the 2 °C threshold, the report finds. And total worldwide carbon dioxide emissions could be halved by 2050 compared to 2013 levels—nearly three-quarters of that from urban sources.
Achieving these goals would cost about $15.4 trillion between 2016 and 2050. That sounds like a lot of money, but it’s less than 2 percent of cumulative world GDP over the same period.
They are lofty goals, projections that even IEA executive director Fatih Birol admits could be impossible to reach.
“We think we are lagging behind strongly in key technologies,” says Birol, “and in the absence of a strong government push, those technologies will never be deployed into energy markets, and the chances of reaching the two-degree goal are very slim.”
To be sure, the Paris agreement represents the strongest statement yet of government intentions to reduce energy use and curb carbon emissions. But as the IEA report states, those goals would require “massive changes in the energy system,” and the national policies required to make those changes are not yet on the horizon.
For example, energy demand from buildings and transportation in cities would be reduced, in the IEA scenario, by 60 percent. In China alone, the number of cars, trucks, and buses is expected to increase from around 100 million today to nearly 600 million by 2050, according to a study from Argonne National Laboratory—an increase that in itself would wipe out the reductions projected by the IEA.
Overall, urban populations are expected to explode in the coming decades, reaching nearly three-quarters of the world's population by midcentury. Most of that growth will occur in the developing world (by 2025, 21 of the world’s 27 megacities, with populations of 10 million or more, will be in developing countries). And studies have shown that city dwellers in the developing world tend to use more energy than their rural counterparts, not less.
The goals laid out by the IEA are not unreachable. But they will require “urgent actions by national governments and local officials so we can employ clean energy technologies much faster than we have done in the last few years,” says Birol. “I am hopeful, but not fully confident.”
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