Why global carbon emissions declined as economies grew

New research has found that, in the past two years, carbon dioxide emissions have declined, largely thanks to China's efforts to reduce its dependence on coal.

Global efforts to curb climate change might be paying off, says a group of international scientists that regularly tracks carbon emissions.

The release of carbon dioxide from burning fossil fuels and from other industries, such as cement production, have slowed “dramatically” in the past two years, perhaps reversing a trend of rapid growth in the last couple of decades.

Reduced coal use in China is largely responsible for the decline, say scientists in a December 7 column in the journal Nature Climate Change.

But they caution that it will take more time to tell if this is just a temporary blip or a budding trend resulting from years of hard work around the world.

"I will take the blip any day; it's much better than saying it's increasing,” US Environmental Protection Administrator Gina McCarthy told the Associated Press at the climate talks in Paris.

“But," she added, "I think it may just represent a strategy that will be more long term."

There have been other periods of low to zero growth in emissions, the research team points out.

They have coincided with shrinking economies during the breakup of the Soviet Union in the early 1990s, the US dotcom bust in the early 2000s, and during the recent global financial crisis.

But what makes the last couple of years most “unusual,” they say, is that emissions are declining while the global economy is actually growing.  

Why?

For one, demand for oil and natural gas has shrunk, while the use of renewable energy has grown dramatically. The capacity of solar installations has exploded, from 3.7 gigawatts in 2004 to 178 gigawatts in 2014. Just in the last year, 40 gigawatts worth of solar-powered energy production was installed around the world.

“Things are going in the right direction,” Janos Pasztor, the UN Assistant Secretary General for climate change told the AP in Paris.

The most important contribution to a decline in global carbon emissions, through, is from China.

It is the world’s largest producer of wind energy, and it's using less coal, the authors say. Though how much less has recently been a subject of great controversy when news broke that China, also the world’s largest CO₂ emitter, had been burning up to 17 percent more coal a year than its government had disclosed.

But it has released revised data, which the study's authors – from the United States, Australia, the United Kingdom, Norway, and Austria – used for their assessment. They project that Chinese carbon emissions will fall by 3.9 percent in 2015, which beats the small rise of 1.9 percent in emissions the group estimated for the country in 2014, and, in comparison, the significant rise of 6.7 percent a year for the decade before that.

Globally, based on data from June to October, the authors estimate emissions will decline by .6 percent this year, an improvement from last year, when they increased by that same amount, and from the decade before that, when they grew by 2.4 percent a year.