beijing’s good air quality streak ends at 43

Beijing’s longest streak of consecutive Blue Sky Days ended last Thursday after an unprecedented 43 days. It was a wonderful start to 2011: the cleanest January since 1998 and average air quality on par with that of the the Olympic and Paralympic Games period.

In my last post, I wondered why the Beijing EPB hadn’t claimed more vociferous credit. A few days later, they did just that. Du Shaozhong, a Deputy Director at the Beijing EPB, gave an “ebullient” interview to Jonathan Watts of the Guardian. (I’m honored that Watts also quoted this blog towards the end of the article.) Director Du described the comprehensive policies that Beijing has adopted to control air pollution, including retrofitting coal-fired power plants, switching home heating from coal to natural gas, implementing progressively stricter tailpipe emission standards, and scrapping older, high-emitting vehicles. He claimed that these efforts have resulted in a “positive, long-term story” of Beijing’s air quality since 1998. The improvements are particularly remarkable given the growth that Beijing has experienced during that time (e.g., the vehicle population increased from 1 million to 4.8 million from 1998 to 2010).

Overall, it’s a strong interview and article full of good information. But it’s also interesting to note what Director Du did not mention:

1) Why was January’s air quality so unusually and dramatically good? Watts writes, “[Director Du] acknowledged that the air quality over the past month had benefited from meteorological conditions – strong winds and cold fronts – but said the improvement was far from a one-off.” The problem here is that the air quality in January was so unexpectedly good that the explanation that it was simply – or mainly – the result of Beijing’s long-term pollution control efforts is unbelievable. Surely the Beijing EPB has some estimate of the contribution of favorable weather / wind to last month’s good air quality, especially considering the Beijing EPB has blamed the weather in the past for poor air quality? If January’s good air quality was “far from a one-off,” does this mean we can expect this much improved air quality to continue? (If it doesn’t, then I will be very curious to see what explanation is offered (if any) when the air pollution levels go back up to more expected levels for this time of year.)

2) It’s true that 2011’s air quality has been very good compared to 1998. But isn’t it disingenuous to claim a consistent trend given the fact that Beijing’s average air quality has stagnated since 2008? Existing control programs have seemingly been effective in maintaining the current air pollution levels in the face of continued rapid growth. Barring continued favorable weather, is there strong reason to expect that the remainder of 2011 will be better than 2009 and 2010?

Leave a Reply