As China continues to crack down on pollution, Beijing's residents are breathing easier and seeing bluer skies.

As reported by Bloomberg, of the seven months with the lowest monthly pollution readings since 2008, five of them have happened since the summer of 2017, with back-to-back low-pollution months this summer in June and July.

"China has made a very clear pledge to 'bring back the blue skies,'" Sydney-based Tim Buckley, director of energy finance studies at the Institute for Energy Economics and Financial Analysis, told Bloomberg. "Hardly a week goes by when China doesn't bring in a new regulation or policy to further this commitment."

Gray skies clearing up

Bloomberg's report relies on the air quality measurements conducted by the U.S. embassy in Beijing. The embassy has an air quality monitor that tracks the presence of particulates less than 2.5 micrometers in diameter (PM 2.5). These particulates of pollution are "fine" enough to directly enter the lungs or even the blood stream, making them a cause for concern.

Since 2008, the months with the lowest average amount of micrograms of particulates per cubic meter were January 2011 (36 micrograms), August 2016 (43 micrograms), June 2017 (35 micrograms), August 2017 (33 micrograms), January 2018 (42 micrograms), June 2018 (42 micrograms) and July 2018 (44 micrograms).

It's worth noting that the air quality in Seattle is downright lousy by comparison, primarily because of smoke drift from the wildfires in California.

As the embassy's website states, the monitor doesn't speak for the overall air quality in the city, just the air quality for the "American community" at the embassy. Still, the numbers do indicate that China's actions to combat air pollution are making a difference in the capital city.

The Summer Palace in Beijing in June 2018 The lakes of the Summer Palace are prettier with less air pollution. (Photo: Ben & Gab/Flickr)

The Beijing Municipal Environmental Protection Bureau stated that the annual average of PM 2.5 in 2017 was lowered to 58 micrograms per cubic meter, a 20.5 percent drop compared to 2016, according to a report by China Daily. The city reported 226 days with excellent and good air quality that year, or days when the PM 2.5 micrograms per cubic meter was 100 or lower.

"The Beijing government spent 22 billion yuan ($3.52 billion) on improving the environment [in 2017], which is an unprecedented amount of investment," Yu Jianhua, chief engineer of the environmental protection bureau, told China Daily in February.

Four gas-fired power plants replaced coal-powered ones around the city between 2013 and 2017, China Daily reported, and demolished coal-fired boilers. Around 50,000 taxis were outfitted with three-way catalytic converters in an effort to reduce vehicle emissions. In addition, the city rolled out clean-energy vehicles for its public transit program.

As MNN reported back in March, China has made significant strides across the country to reduce pollution between 2013 and 2017. In the Beijing-Tianjin-Hebei region, researchers found that PM 2.5 concentrations fell by 36 percent over those same four years. They also determined that Beijing residents could expect, on average an additional 3.3 years of life as a result of the government's anti-pollution efforts.

Still a ways to go

Even though Beijing has experienced low pollution readings this year, the city still isn't out of the woods. An October 2018 study from Harvard University shows that the city still suffers from extreme levels of smog during the winter.

Researchers say they may know why. The government focused its efforts on reducing sulfur dioxide emissions from coal plants, but wintertime air pollution is linked to formaldehyde emissions.

"By including this overlooked chemistry in air quality models, we can explain why the number of wintertime extremely polluted days in Beijing did not improve between 2013 and January 2017 despite major success in reducing sulfur dioxide," said Jonathan M. Moch, a Harvard University graduate student and first author of the study. "The sulfur-formaldehyde mechanism can also explain why policies seemed to suddenly reduce extreme pollution last winter. During that winter, significant restrictions on SO2 emissions brought concentrations below levels of formaldehyde for the first time, and made SO2 the limiting factor for HMS production."

Chemical and oil refineries and vehicles are the primary sources of formaldehyde, and researchers recommend the government also focus on reducing emissions from these sources.

Editor's note: This article has been updated since it was originally published in August 2018.

It's easier to breathe in Beijing these days
Five of the best 7 months for Beijing air quality have occurred since last summer.