Archive for February, 2011

xinhua english reports on beijing’s pollution, using usa terminology

Thursday, February 24th, 2011

As I was writing my post yesterday, Xinhua English published a short piece on this week’s heavy pollution episode in Beijing:

BEIJING – Heavy fog with a visibility of around 1 km persisted in Beijing for a third day Wednesday, keeping the city’s air pollution at the most hazardous levels measured this year.

The municipal environment bureau’s readings indicated the heaviest air pollution on Wednesday was monitored in Daxing district in southern Beijing, where the air quality index (AQI) reading hit 362.

The AQI ranges from 0 to 500: the higher the number, the more severe the pollution. Readings over 300 are considered hazardous.

The average AQI reading for the city Wednesday was 207, down from 270 on Tuesday and 333 on Monday.

The highest AQI reading over the last three days – at 394 – was recorded in the eastern Chaoyang and northern Haidian districts on Tuesday.

The Beijing Meteorological Bureau said a weak cold front would hit the city on late Wednesday to dispel haze. Winds, however, were unlikely to completely clear the air pollution on Thursday.

The article seems fairly straightforward, though there is one very surprising detail: the terminology they are using to describe the air pollution is the United States’ terminology, not China’s. Two differences:

1) China’s own index is called the Air Pollution Index (API), not the Air Quality Index (AQI), which is what is used in the US.

2) China’s system does not use the word “hazardous” to describe index levels above 300. “Hazardous” above 300 is the US’ terminology. China’s system simply calls this “heavy pollution” (重污染), without a value judgment of the danger. (“Hazardous” might be better translated as 危险 or 有害.)

Does this shift signal the impact of the US’ Embassy’s BeijingAir Twitter feed on guiding air quality discussion, at least among the English-speaking population in Beijing, or am I reading too much into it? (I asked similar questions in two posts in 2009 when the English-language China Daily openly questioned China’s system in light of the Embassy’s data.)

Regardless, Chinese language sources appear to be uniformly using the Chinese terminology. This Xinhua article in Chinese even includes a glossary, though it carefully avoids any judgments like “hazardous,” preferring the less direct “heavy pollution” (重度污染). The article does note, though, for index levels above 300, “elderly people and those with heart or lung diseases should remain indoors and reduce physical activity…and…the general population should avoid outdoor activity.” (老年人和心脏病、肺病患者应停留在室内,并减少体力活动…一般人群应避免户外活动。)

beijing’s air is mashed potatoes

Wednesday, February 23rd, 2011

Fresh off its unexpected best month of air quality since 1998, Beijing plunged head first this week back into mashed potato air quality. Mashed potato (scientific term, I promise) air looks like this from the ground (taken around 4pm today):

and this from space (2/20 photo from NASA):

From a data perspective, mashed potato air means three consecutive days of MEP’s API above 200 (including a 2/20 peak of 333 – equivalent to a daily average PM10 concentration of 446 ug/m3), the US Embassy’s BeijingAir Twitter feed consistently reading “Hazardous” or “Beyond Index” (PM2.5 concentrations peaking above 500 ug/m3), and the China National Environmental Monitoring Center’s new hourly air quality data showing…well, no particulate matter data at all for at least the past 48 hours for most centrally-located stations. This is disheartening, because it’s extreme episodes like this during which people – especially at-risk populations – need that data the most. The Wanshouxiguan (万寿西官) station does have hourly PM10 data, which show a peak near 480 ug/m3 (graph below shows that station’s hourly PM10 data from 2/21 6pm to 2/23 6pm):


For context, remember that the WHO’s daily recommended PM10 limit is 50 ug/m3, while the annual limit is 20 ug/m3.

Unfortunately, I have no time this week to run additional data analysis or provide more lengthy commentary, though I would like to repeat my previous comment about the Beijing EPB’s claims of credit for January’s excellent 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.)” The Beijing EPB issues monthly air quality summaries on the last day of each month, so let’s see what they say next Monday.

Lastly, just one criticism of the AFP story that’s going around:

BEIJING — Thick smog blanketing Beijing went “beyond” measurable pollution levels on Monday, the US embassy said, as a Chinese official warned people to stay indoors and avoid outdoor activities.

Actually, the pollution levels are still measurable, and reported. You can still see the pollution level, as highlighted here (in this case, a PM2.5 concentration of 515.0 ug/m3):

PM above 500

“Beyond index” doesn’t mean the pollution can’t be measured, it just means that the pollution level is beyond the US’ standard system for categorizing, which maxes out at 500. (Though we all know what it’s really called.)

note to la times: this is not what beijing looks like

Wednesday, February 9th, 2011

The LA Times reported yesterday on a new study suggesting that cancer risks for people living in Beijing would be halved if the air quality were consistently as good as it was during the Olympic Games. (This result, while noteworthy, is not that surprising given the fact that air pollution levels were half of what they normally are during that time period.)

Check out the shocking lead photo:

la times feb 8
The caption reads, “This photo, taken in Beijing a few years before the 2008 Olympics, shows bicyclists passing a factory emitting smoke into the air.” The choice of this photo really bothers me, for several reasons. The biggest reason is because this isn’t what Beijing looks like. I might believe that this was taken in Beijing’s rural suburbs, but to imply that average life in Beijing is something like that in this picture is truly manipulative and biased. I presume it is a stock photo chosen by some editor who has never been to China and simply wants a “shock” image that plays right into the idea that China’s environmental crisis is straight out of a Dickens novel. Secondly, this picture is not only from a few years ago, it’s clearly from the summer (the bicyclists are wearing T-shirts), making it doubly inappropriate for printing now. Third, the photo blatantly contradicts the fact that Beijing just completed its cleanest month in a decade, something the LA Times could not be bothered to cover, or even mention in this article.

For a stark comparison, this is the photo the Guardian ran last week in its story about Beijing’s air quality:

guardian feb 2

Hmm. I just discovered that the photo chosen by the LA Times just happens to be the first photo result in a Google Images search for “Beijing Pollution.” Surely the explanation isn’t that simple?

beijing pollution images

beijing’s good air quality streak ends at 43

Wednesday, February 9th, 2011

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?