Video: The "airpocalypse" of smog swirling over Chinese cities has reached its most dangerous levels yet. Beijing issued its first-ever red alert today, closing schools and taking cars off the road. How bad is it? According to US guidelines levels are at 6: "Everyone should avoid all outdoor exertion."
While the short-term effects of being exposed to smog like this are scary -- irregular heartbeat, asthma, respiratory problems -- even lower levels can have devastating long term effects. In China, about 4000 people die from premature deaths due to pollution every day. That's 1.6 million people a year.
At the COP21 summit this week in Paris, China's leaders have made some pretty significant pledges to close its coal-fired power plants, a huge contributor to the poor air quality. Let's hope those pledges stay intact.