As the map above shows, China is home to many of the world’s most polluted cities. The map was created by AQICN, a Chinese website that tracks global air pollution stats.
Ulf Troeng, who told me about the map, clarifies that:
“Data is not available from all countries, it is mostly collected from the developed part of the world. But anyway, the map gives you a pretty good picture of where the air is clean and where it is dirty. In that way it also says something about where sources of pollution are located.”
The numbers refer to the Air Quality Index (AQI) which uses the following scale:
- 0 – 50: Good, Air quality is considered satisfactory, and air pollution poses little or no risk
- 51 -100: Moderate, Air quality is acceptable; however, for some pollutants there may be a moderate health concern for a very small number of people who are unusually sensitive to air pollution.
- 101-150: Unhealthy for Sensitive Groups, Members of sensitive groups may experience health effects. The general public is not likely to be affected.
- 151-200: Unhealthy, Everyone may begin to experience health effects; members of sensitive groups may experience more serious health effects
- 201-300: Very Unhealthy, Health warnings of emergency conditions. The entire population is more likely to be affected.
- 300+: Hazardous, Health alert: everyone may experience more serious health effects
The Data sources used for the Air Quality, Air Pollution, PM2.5 (fine particulate matter), PM10 (respirable particulate matter), NO2 (nitrogen dioxide), SO2 (sulfur dioxide), CO (carbon monoxide), O3 (ozone)
As you can see in the map above, 3 cities in Western China (Korla, Aksu & Kashi) all had the worst possible score of 999, when the data was checked, with many others falling into the Unhealthy or Very Unhealthy category.
So any of the three could be considered as having the world’s worst air pollution problem. Contrast them with Japanese cities next door or ones in North America, Europe and Australia below:
While a long way from perfect, air pollution levels are noticeably lower in all regions compared to China. Want to learn more about air pollution in China and around the world? Be sure to visit http://aqicn.org and have a look at:
- The River Runs Black: The Environmental Challenge to China’s Future, Second Edition
- Clearer Skies Over China: Reconciling Air Quality, Climate, and Economic Goals
- This Changes Everything: Capitalism vs. the Climate
Have any thoughts? Leave them in the comment section below:
Francesco Basenghi says
March 16, 2015 at 2:14 pmHi, is it possible to know why Italy has no datapoint in the European Map.
I’ve tried to dig up the the datasource used but I wasn’t able to figure it out.
Being Italian I have some intresto on why data form my country is not available.
Thank you very much.
[Great site, I enjoy these visualizations very much]
Brilliant Maps says
March 16, 2015 at 6:22 pmUnfortunately I don’t know, although it does seem like a rather big oversight.
KF says
June 3, 2015 at 9:46 pmwhy isn’t India given a mention, as far as I can see?
Ili says
December 21, 2015 at 4:02 pmThe whole thing looks like as if it was done by someone who has no idea about the whole air pollution thing. I bet that cities in India are just as polluted, it’s just that China is really very good at measuring air pollution, if you write the name of any city in baidu it will tell you the number. Tell me which other country has something like this?
I mean, I’m not trying to say that China is not polluted – it is, as hell, but just look at the photos from India, they look at least just as bad as photos from China. What’s with that childish title? And then, as the very impolite proof of the fact that this is not the very most trustworthy article ever – since you write Aksu and Korla, then you should also write Kashgar, since Xinjiang is an autonomous region and the language used there is Uyghur, not Chinese. If you instead write Kashi, then you should also write Akesu and Kuerle, as they are called in Chinese.
And also, pointing out these three cities because you’ve seen the ‘999’ thing… Well, you should consider the fact that the biggest city in Xinjiang has the population of much less than 2 mln people, and it’s none of these three. Wtf, it’s all desert and steppe! Maybe there was a sand storm, lol. This is a mistake, and it’s so obvious that it made me angry.
It makes China look like the only irresponsible country in the region. And it maybe is on top of the list, or even the very first, but it at least has the complete record. Which India, Pakistan, Indonesia etc. don’t have.