That picture might even have been taken during the impressive sand storm over Beijing in April this year [2], that's the most foggy day I've seen in the last 12 months here. Looking at the sand storm coming and swallowing the buildings from our offices on 10th floor was quite impressive. :-)
Also, if you live in a big city on any continent, you might want to check your own pollution levels using the AQI site [3], you might be surprised by the results. ;-)
[1] https://www.youtube.com/watch?v=lp7nLlaLaBg
[2] http://www.huffingtonpost.com/2015/04/16/beijing-sandstorm_n...
http://www.scmp.com/news/china/article/1127398/smog-threat-r...
(date taken from the wsj thing http://blogs.wsj.com/photojournal/2013/01/14/photos-of-the-d...)
VERY UNHEALTHY
298: http://aqicn.org/city/chicago/
UNHEALTHY
170: http://aqicn.org/city/usa/washington/seattle/beacon-hill/
UNHEALTHY FOR SENSITIVE GROUPS
122: http://aqicn.org/city/beijing/
MODERATE
96: http://aqicn.org/city/usa/oregon/portland/
70: http://aqicn.org/city/tokyo/
66: http://aqicn.org/city/berlin/
65: http://aqicn.org/city/london/
61: http://aqicn.org/city/hongkong/
54: http://aqicn.org/city/newyork/
GOOD
33: http://aqicn.org/city/zurich/
31: http://aqicn.org/city/stockholm/
24: http://aqicn.org/city/paris/
13: http://aqicn.org/city/california/san-francisco/san-francisco...
It appears to be true that you can have a bright mostly clear day and very high levels of fine particulate pollution.
This haze is part of what contributes to smog when combined with other more visible (course particulates) pollution. But these fine particulates don't appear to be the product of fireworks as suggested below, and are more likely to be the product of the coal power stations.
The measure for Chicago is probably skewed by one of the measuring stations being nearer to, or down-wind from, a coal power station.
For example, the previous posted said Paris was 24, Paris - where I am now, with the window open, slightly after midnight - is currently reporting 53.
Kunming, a city of 6+ million where I usually live in China's southwest, is a little higher at 68. (This counters the 'China is dirty' western media BS)
Sydney, where I grew up, is higher at 75. However, in another reading closer to the area of town where I used to live it's much lower at a mere 13.
So, check which part of the city you are looking at and what time of the day the reading was taken. Also, don't assume all of China is all dirty and horrible like the east coast megacities (though much of it may be, to varying extents).
It's anecdotal, I know, but I wonder about some of this data.
http://efisherhistory12.weebly.com/uploads/2/3/5/2/23527216/...
Credit where it's due, Twitter. That Beijing photo is by @nntd and first appeared here http://blogs.wsj.com/photojournal/2013/01/14/photos-of-the-d...
It is probably way lot worse now. I saw this documentary recently, https://www.youtube.com/watch?v=T6X2uwlQGQM it is a good watch. FYI China is also destroying marine life in the West Philippine Sea http://globalnation.inquirer.net/120699/ph-slams-china-for-d... http://www.philstar.com/headlines/2014/05/12/1322282/photos-...
In comparison, Beijing is routinely 500+. Manhattan is about 40. And some parts of the west coast push 100+, most likely because of Chinese air floating all the way over the Pacific.
That's insane. Copenhagen is at 80.
It's not everyday, but when the 'Jing has a bad day, it's really something else. I don't know how people live there, it's terrible and you can just feel it damaging your lungs. It encourages this positive feedback loop too - the pollution is so bad you want to take a car everywhere, which of course contributes to the pollution!
I wouldn't be surprised if a fair portion of uber's success in CN is due to people not wanting to walk in the toxic smog. Would be interesting to see a graph of pollution index vs. ride numbers.
[edit: positive not negative]
Also, uber isn't that successful in the jing, taxis are cheap enough (and ya, there is an uber-like app for them), and if you want to go upscale there is didi zhuanche (same app). You either take a car or a taxi, if you can afford $5-$10, or a bus/subway/bike if you can't, pollution doesn't really affect that.
Certainly I'd spend a couple bucks more to sit for an hour (or more!) in an audi or VW over a hyundai..
As a kid growing up in Europe, I remember pollution and acid rain and whatnot being a hot topic on the news every night. Its okay today, but it took time and it will take time in China also, but the government there is doing something about it for sure.
http://www.vancouversun.com/news/Smoke+creates+eerie+morning...