It’s common knowledge that the air in China is bad. After all, the country uses 50% of the world’s coal.
But just how bad the air is – is it unhealthy or lightly polluted? – is more than just semantics. It’s been the source of debate and controversy between the US and Chinese governments. In 2008, the US embassy in Beijing started tweeting hourly air conditions for the US expatriate community. According to sources inside the embassy at the time, the readings created tension with the Chinese government, who asked the embassy to shut down the feed (twitter is blocked in China, but expats and locals find ways around the great firewall). The US continued monitoring the air and tweeting, but reiterated the point that the index measured a sole point in Beijing and was neither scientific nor representative.
Last week the embassy released historical data going back to 2008. In one chart, this is what the air quality looks like in Beijing:
The data include over 49,000 hourly readings between April 2008 and March 2014. While some data is missing and others had to be thrown out (negative readings were ignored), here are few depressing stats from the data:
- Average AQI levels jump in the winter, when coal-fired power plants rev up to meet heating demands from the more than 20 million residents in Beijing.
- Confirming residents’ perceptions, hazardous days are becoming more commonplace, as are higher readings. In 2013, 5.3% of all hourly ratings were ranked as hazardous, up from 2.9% in 2009.
- Taking the data from 2008, crunching the numbers and then translating that into a yearly figure, Beijing’s residents breath in a full two weeks of hazardous air, another month of very unhealthy air, 5 additional weeks of unhealthy air and 8.4 weeks of unhealthy air for sensitive groups (looking at you, grandma and small children).
Data from 2014 shows an already apocalyptic year, but here’s hoping government measures to clean up the air will help (for more on the topic, see air and emissions expert Vance Wagner’s predictions here).