For the second year in a row, the global economy has grown while fossil fuel emissions stayed level, the International Energy Agency announced today. It might sound boring, but it’s big news.

Here’s why: Ever since humans began burning fossil fuels, economic growth and fossil fuel emissions have followed a nearly identical trendline. When fossil fuel use rises, the economy does well. When emissions drop, the world dives into a recession.

Greenhouse gas emissions need to decrease dramatically — or we face environmental and human disaster. For this to happen, the two trend lines must diverge. No political leader can advocate for decreased fossil fuel use if this guarantees economic collapse.

In theory, economic growth and emissions don’t need to rise and fall in lockstep. Alternative energy could fuel growth as well. But, historically few places in the world have shown this to be the case. Some parts of Europe are the exception — Sweden, for example, has seen its economy grow 55 percent in 25 years, while emissions decreased by 23 percent.

In 2014, for the first time ever, global economic and emissions growth decoupled — the world got 3 percent richer while fossil fuel emissions stayed the same. It was an important moment, though some argued it was a blip rather than a trend.

The preliminary data from 2015 say otherwise.

A surge in alternative energy, which accounted for an impressive 90 percent of new electricity generation last year, made the emissions-free growth possible. Emissions decreased in both the United States and China — the two most significant consumers of fossil fuels.

As poorer parts of the world claim their pieces of the economic pie, demonstrating this uncoupling is crucial. They look to the United States and other developed countries to say — Hey, you guys got rich off the back of cheap fossil fuels, and now it’s our turn. India, poised to become the world’s most populated country and biggest economy in the coming decades, is currently grappling with plans to expand both coal and wind energy, to satisfy exploding power demand.

If the world is going to avoid climate catastrophe, emerging economies need to hear the message that fossil fuel expansion is not a necessary factor for growth. It makes the pleas to developed nations — that they must not burn fossil fuels because the global budget has been spent — slightly less sour to the taste.

Photos via Stuart Rankin / Flickr