#theairweshare: Five air quality insights for the UN International Day of Clean Air

Berkeley Earth has been providing open-source air quality data and analysis since 2015, when we first published our findings mapping the concentrations and sources of air pollution in China. In recognition of the UN’s 2022 International Day of Clean Air, below are five resources highlighting both the challenges and opportunities of tackling one of the greatest global health issues facing the world today. 


1) In one of the world’s most polluted cities, PM2.5 has been steadily decreasing since 2016

Graph depicting the 7-day average of hourly PM2.5 concentration observations recorded at both the US Embassy in Beijing, as well as from the Chinese Network.

Often referenced as having the worst air pollution in the world, Beijing’s aggressive clean air policy has led to a marked reduction in the concentration of PM2.5 since 2016. 

With an average annual PM2.5 concentration of 27 µg/m3 over the last year, Beijing’s improved air quality is still over 5x the exposure considered healthy according to the WHO’s updated 2021 guidelines, and falls in the “Moderate” category according to the U.S. EPA’s rankings. 

Click here for additional real-time and historic air quality data and analysis for Beijing.

2) Wildfires in the Western U.S. are having a measurable impact on average U.S. PM2.5 concentration

In a 2021 Q&A , Berkeley Earth climate scientist Zeke Hausfather coined the phrase “smoke season” in reference to the pervasive wildfires across the western U.S. that have come to mark late summer and early fall. We are now seeing the impact of “smoke season” reflected in the elevated national average air quality as a whole. 

While clean air policy and air pollution mitigation strategies have had a positive impact on lowering average PM2.5 concentrations in many countries, the significant wildfire events in the western United States have led to a measurable increase in the national average PM2.5 concentration over the past few years.

The impact of wildfire smoke on air quality is further evidenced in the long-term PM2.5 concentration trends across western U.S. states such as California and Colorado. 

Additional real-time and historic air quality data is available via the links below: 

3) Air pollution is costing the world’s citizens 2.2 years of life on average, according to EPIC’s Air Quality Life Index (AQLI)

In 2021 the World Health Organization issued an update to global air quality guidelines for the first time since they were first published 2006, significantly lowering the benchmark for the PM2.5 concentration considered “healthy” from 10µg/m3 to 5µg/m3; more than97 percent of the planet now breathes air considered to be “unhealthy” according to the revised guidelines. 

To discuss the implications of the WHO’s 2021 update, the research behind the AQLI’s global life expectancy metrics, along with both the challenges and opportunities facing action on global air pollution, we are honored to welcome back Christa Hasenkopf, Director of Air Quality Programs and the AQLI at the Energy Policy Institute at University of Chicago (EPIC), for her second interview with Berkeley Earth’s Data Points podcast. 

On the impacts of air pollution relative to other causal factors of global mortality: 

“So I think the impacts are not just about life expectancy, but also quality of life and our ability to think clearly, which is a little bit staggering. And to your question around, ‘How does this compare to other causes or risks of death globally,’ that’s also staggering: so PM2.5 pollution was responsible for more than two years of life that are lost from average life expectancy across the world. That’s comparable to smoking, that’s about double alcohol use or say unsafe water and sanitation. And it’s more than road injuries, HIV/AIDS, malaria, and war combined. So it has a huge impact on global health.

On the impact case for funding air quality data and infrastructure: 

“I think looking globally, I think data collection, opening up data, and even bigger picture, I’d say air quality management, is probably the lowest-hanging fruit in terms of addressing air pollution. And from both effectiveness and also even just funding capacity: it’s low-hanging fruit to get existing data that has been generated by governments or other actors out there into the world, but there isn’t capacity to make that data open. It’s low-hanging fruit to put up a monitor, a single monitor, in a country that doesn’t have any long-term air quality monitoring […]Because any solution that one wants to fund or build is, at the end of the day, going to rely on data to understand what that progress looks like, whether that’s to iterate, change course, or to keep going.”

Click here to listen to the full interview.

4) Berkeley Earth’s PM2.5 Cigarette Equivalence

In 2015 Berkeley Earth derived a rough conversion for the equivalence between PM2.5 pollution and cigarette smoking, finding that a PM2.5 concentration of 22µg/m3 is approximately equivalent to smoking one cigarette. 

Similar to the health impacts of the cigarette smoke equivalent, air pollution is changing cancer epidemiology: In a 2021 interview on Berkeley Earth’s Data Points podcast, Dr. Vinnet Khanna discussed the significant increase in the percentage of non-smokers presenting with lung cancer and other pathologies in India’s major cities. Dr. Khanna’s paper, which references Berkeley Earth’s cigarette equivalence, suggests the need for increased lung cancer screening for non-smokers in regions with significant air pollution exposure. 

Click here to access the full text of Berkeley Earth’s Cigarette Equivalence memo. 

5) Visualize your own cigarette equivalence on the Shoot! I Smoke app

Last but not least, consider taking a look at this creative adaptation of Berkeley Earth’s cigarette equivalence: the Shoot! I Smoke app, developed by designer Marcelo Coelho and developer Amaury Martiny, translates local AQI data into cigarette exposure using Berkeley Earth’s equivalence, creating an accessible and compelling visualization of the impacts of air pollution. 

Click here to find the cigarette exposure at your location.


We have updated our Privacy Policy to reflect the use of personalized advertising cookies placed on our website. By continuing to use our site, you acknowledge that you accept our Privacy Policy.

I accept