Greenhouse Gas Emissions Rose Last Year. Here Are the Top 5 Reasons.

https://www.nytimes.com/2018/03/22/climate/global-energy-demand.html

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WASHINGTON — If the world wants to avoid drastic global warming this century, we’ll need to reduce our greenhouse gas emissions sharply in the years ahead.

For now, however, we’re still moving in the opposite direction: Carbon dioxide emissions from the use of coal, oil and natural gas increased 1.4 percent globally in 2017 after holding steady for the previous three years, the International Energy Agency reported on Thursday. That’s the equivalent of adding 170 million new cars to the road worldwide.

The energy agency, which called the findings “a strong warning for global efforts to combat climate change,” detailed several big reasons CO₂ emissions are increasing again. Here’s a look at the main ones:

Roughly two-thirds of last year’s emissions increase came from Asia, where fast-growing countries like China, India and Indonesia continue to rely heavily on fossil fuels as they lift themselves out of poverty.

China, which is responsible for one-quarter of the world’s industrial greenhouse gases, saw its emissions rise 1.7 percent in 2017, fueled by rapid economic growth and an increase in oil and natural gas use. The rest of developing Asia, including India and Indonesia, saw their overall emissions increase 3 percent.

That jump in Asian emissions overshadowed cuts made elsewhere in the world: The United States, for instance, reduced its emissions 0.5 percent last year, driven by the growing deployment of renewable energy. Britain, Mexico and Japan also managed to cut their emissions. (The European Union over all, by contrast, saw emissions rise 1.5 percent.)

Renewable energy — including wind, solar and hydropower — was the fastest-growing energy source worldwide in 2017. China alone installed as many solar panels last year as the entire solar capacity of France and Germany combined. And the prices for renewable technologies keep falling.

The catch? Last year’s “unprecedented” growth in renewables, the I.E.A. said, satisfied only about one-quarter of the increase in global energy demand as the world’s economy boomed. Fossil fuels supplied the rest. “The overall share of fossil fuels in global energy demand in 2017 remained at 81 percent,” the agency’s report said, “a level that has remained stable for more than three decades despite strong growth in renewables.”

If the world wants to cut emissions quickly and meet the climate goals laid out in the Paris Agreement, the I.E.A. said, clean energy will need to grow about five times as fast each year between now and 2040 as it did last year.

Over the past few years, coal demand has plummeted around the world as countries like the United States and China shift away from the most carbon-intensive of all fossil fuels. China, for instance, has been pushing to phase out coal use in residential heating in order to clean up the severe air pollution that is choking its cities.

But coal use rebounded slightly in 2017, rising by 1 percent, driven in part by an increase in coal-fired power in Southeast Asia. A particularly hot summer in China also led the country to run its existing coal plants more often to power air conditioning.

Yet despite last year’s uptick, there are signs that coal is falling out of favor worldwide. India’s coal demand is growing at a slower pace than it did over the previous decade, as the country turns to solar power and other clean energy sources. And, the I.E.A. said, both China’s and the world’s coal consumption remains below the 2014 peak.

Demand for oil rose 1.6 percent last year, much faster than the average annual pace over the previous decade. As oil prices have declined, more people in the United States and Europe are buying larger S.U.V.s, pushing up transportation emissions further.

The I.E.A. noted that electric cars, which do not use oil, are quickly making inroads in countries like China, as a result of aggressive government mandates and falling battery prices. “For now, however, the strong growth in electric-car sales remains too small to make a dent in oil demand growth,” the agency said.

In addition to switching to cleaner sources of energy, countries can also curb their emissions by improving the energy efficiency of their factories and homes and vehicles, through policies like building codes and fuel-economy standards.

On this score, however, the I.E.A. had bad news: In 2017, the energy intensity of the global economy — a measure of efficiency — improved by just 1.7 percent, a slower pace than in each of the previous three years. The agency noted that many countries appear to be easing up on government policies to improve energy efficiency.