The good news: NASA scientists can see through satellites that air quality has improved over much of the United States, by tracking the nitrogen dioxide emitted from cars, power plants and other fossil-fuel burning technologies.

The bad: places like China and others parts of the world have only increased the emissions over the last decade, according to a series of new images released the space agency and published in the Journal of Geophysical Research.

“These changes in air quality patterns aren’t random,” said Bryan Duncan, a NASA scientist and author of the paper. “When governments step in and say we’re going to build something here or we’re going to regulate this pollutant, you see the impact in the data.”

Nitrogen dioxide is yellow-brown gas with an acrid smell commonly emitted by cars, power plants and industrial operations. In high enough concentrations, it can cause major health impacts in the form of ground-level ozone within city smog.

But different parts of the world are handling the phenomenon differently.

Western Europe saw a 50 percent decrease in the nitrogen dioxide emissions trackable by the images, from 2005 to 2014. Likewise, the United States saw startling reductions of nitrogen dioxide by as much as 50 percent hovering over its metropolitan areas, but especially in the Northeast and the Midwest. Entire areas that had been red are now a shade of blue.

At the same time, China experienced increases of as high as 50 percent virtually everywhere as it continues to develop, and has continued to lie about its pollution levels. Within that larger increase, however is a burgeoning middle class in some cities, like Beijing and Shanghai, which appear to have cleaned up their environment enough to show nitrogen reductions on the images, which were taken from the NASA Aura satellite.

Other changes are more nuanced – but still show humanity’s fingerprint on the very air of the Earth. As Syria descended into chaos with its multi-factional civil war, its nitrogen dioxide levels virtually disappeared as its economy was derailed. In the area around Johannesburg and Pretoria in South Africa, the metro area showed both decreases in the nitrogen dioxide, due to electric cars and cleaner power plants, and increases attributable to booming mining and heavily industrial operations outside the city.

“Until we had this new space view, it was a mystery,” said Anne Thompson, a co-author at NASA.

Read more: Climate Change Agreement Reached – But Opposition Remains

In the U.S., one of the places that saw increases in the nitrogen dioxide were North Dakota and Texas, both of which showed a 30 percent increase of the gas in their respective atmospheres, likely due to fracking.

The images were released this week, in the wake of an historic climate change agreement reached in Paris by about 190 of the world’s nations. However, the disparity between developing and developed nations has shown that some of the richer countries have already mitigated their polluting factors, while countries undergoing boom times have seemed less likely to want to offset their environmental footprint.