Archive for the ‘beijing’ Category

massive us embassy pm2.5 data dump

Tuesday, April 15th, 2014

Incredible! The State Department has released six years of hourly PM2.5 data from the US Embassy in Beijing. The data is actually wonderfully well-organized (kudos to whoever formatted it and prepared it for release!), and is just begging to be dug through. Here are some initial discoveries and thoughts based on a few hours of playing around with the data. (See also some good initial analysis from Wayne Ma/WSJ here and here.)

The Dataset
The dataset contains nearly 50,000 hourly readings from April 8, 2008, to March 31, 2014. There are some gaps in the coverage, but overall the data are fairly comprehensive. (It’s also clear that the reliability of the monitor – or maybe the reliability of maintenance – improved over time.) The data are exclusively hourly PM2.5 readings from the single monitor at the US Embassy. Because the data are in hourly concentrations of PM2.5, they must be processed into daily average concentrations and then converted to AQI. There are no ozone data, nor data from other monitors around the country or world. (Yet.)

The Best and the Worst
– Best hour: 9/28/2012 at 9am and 2pm: 0 ug/m3. Astonishing!
– Best day: 9/28/2012: 3 ug/m3
– Worst hour: 1/23/2012 at midnight: 994 ug/m3
– Worst day: 1/12/2013: 569 ug/m3
– Biggest single-hour change: 11pm to midnight, 1/22-23/2012: +769 ug/m3
– Longest streak of Unhealthy air (>150 ug/m3): 161 hours (2/19-26/2014)

Yearly Averages
The following figure shows Beijing’s yearly average PM2.5 levels according to the US Embassy monitor. Also shown on the figure are the US annual average PM2.5 standard (12 ug/m^3) and China’s (35 ug/m^3).

beijing yearly average pm25 2008-2014
The data, of course, show that Beijing’s air quality is atrocious, with annual average PM2.5 many times higher than recommended levels. But what about the trend? Well it’s actually not clear. Obviously the first quarter of 2014 has been terrible, but that could be just the season (see next graph). 2013 was slightly worse than 2012, but that’s not a trend; 2012 may have been abnormally clean. Overall, it looks like Beijing’s air has not gotten demonstrably worse or better over the past six years.

Monthly Averages
From these data we can take a first look at seasonal periodicity in PM2.5. This graph shows monthly average PM2.5 levels over the entire dataset (note: I should really show error bars in this, but don’t have the time to put that together right now and anyway this isn’t peer-reviewed, just a quick look):

beijing monthly average pm25 2008-2014
This is a strange pattern that I’m not sure how to interpret. It does seem to make intuitive sense that the winter months would be worse, but why also June and July? Perhaps the answer lies in the weather and wind patterns of the spring and fall that help disperse pollution, but that’s just a guess.

Let’s look at the entire time series (monthly averages):

beijing month average pm25 2008-2014
This is way less clean/clear. The extreme variability of the monthly air quality jumps out immediately, especially January 2013 and February 2014 (worst months), as well as January 2011 (best month).

Hourly Averages
Ever wonder how Beijing’s pollution changes over the course of the day? Well, take a look:

beijing hourly average pm25 2008-2014I’d say that looks like a pretty clear trend, with PM2.5 surging during evening rush hour and remaining high into the early hours of the morning. Is this linked to motor vehicle patterns (including trucks entering the city at night?) or related to diurnal weather patterns? I’m not sure yet, but certainly worth closer look and investigation.

Finally, at the risk of showing too much in one table, here’s the percentage binning of days by US AQI category in each of the years (further description of these bins is here).

2008-2014 beijing air quality by category
As also noted by Wayne Ma in WSJ, nearly half of the days are deemed “Unhealthy” by the US EPA. (I haven’t compared these yet against the Chinese scale, as Wayne did.) It’s clear that Beijing and the national government have a lot of work left to do. But really we knew that before we had 50,000 data points to prove it.

Next Steps
I get asked all the time by researchers if I have these data; I’m so glad that State has finally put them out there public. I’ve just scratched the surface here, and I’m really looking forward to seeing the further analysis people come up with. If I have time I’ll post some more analysis this week. Now if only the Chinese National Environmental  Monitoring Center would do a similar data dump…

2014: first tests of China’s major air quality improvement plans

Friday, January 3rd, 2014

Happy New Year!

I was asked to contribute a short essay to China Dialogue’s New Year’s “Predictions for China’s environment in 2014.”

They’ve given me permission to re-post here. Originally posted, in English and Chinese, at China Dialogue:

2013 will be remembered in China as the year of the “airpocalypses.” Smoggy skies throughout the year (e.g. Beijing in January, Harbin in October, Shanghai in December) drew unprecedented attention from the media, the general public, and China’s leaders. The Chinese government responded by issuing a surprisingly aggressive series of new plans and regulatory actions. The most important of these, September’s State Council Air Pollution Prevention and Control Action Plan, establishes new binding air quality improvement targets for cities, mandates a host of specific pollution control actions such as fuel quality improvements and regional coal caps, requires cities to adopt emergency pollution response plans, and much more. Some provinces and cities also issued their own, detailed set of additional directives; Beijing famously “declared war” on PM2.5 before releasing its 84-point plan.

If 2013 was the year so many government air quality plans were forged, 2014 is the year they will begin to be wielded. A few examples from the transport sector specifically: starting January 1st, the nationwide implementation of a cleaner gasoline standard means that all cars will emit less pollution; a parallel cleaner diesel standard will follow by the end of the year. In Beijing, new limits on the population of vehicles will make winning the city’s notorious license plate lottery even more unlikely, while thousands of electric and gas-fuelled buses and municipal trucks will begin to hit the streets. 2015 and beyond will bring even more aggressive goals, especially sweeping new regulations and targets for the greater Beijing, Yangtze River Delta, and Pearl River Delta regions.

Of course, ultimate success will be evaluated not by how many directives the government issues – or even on how well they are implemented and enforced – but rather on actual, measured improvements in the air people are breathing. China’s recently completed, extensive air quality monitoring network publicly broadcasts hourly, real-time air quality data, data that will be watched closely by the media, public, and government alike. Unfortunately, even with China’s new, comprehensive air quality improvement plans, solving the air pollution crisis will likely take many years. Whether China’s public has the patience to endure a few more years of poor air quality (and inevitable, occasional airpocalypses) while the lengthy clean-up unfolds may be just as interesting to watch in 2014 as the plans and policies themselves.

the solution to beijing’s pollution is…controlling barbecues?

Wednesday, October 16th, 2013

Over the past few months, there have been a few suggestions from Chinese researchers and officials that Beijing’s government should go after cooking, especially outdoor barbecues, as a way of controlling air pollution. Back in May, I was quoted in the WSJ’s China Realtime Report questioning this strategy, noting my opinion that because barbecue emissions are very minor compared with emissions from motor vehicles, power plants, and industrial sources, I think it’s misguided and unfair to target the wonderful Beijing institution of outdoor chuanr. (At a deeper level, I am also concerned about the idea that average people (laobaixing) should be blamed for pollution or should have to “share the burden” to make the skies blue. The primary burden of action for the next decade falls primarily on government and industry.)

In any case, last week, cooking-as-a-pollution-source was back in the news, with another official highlighting the need for Beijingers to contribute to the air quality improvement efforts by, apparently, modifying their cooking practices. (There is even a debate going on about the differing PM2.5 impacts of different regional cuisines.) As noted in a nice summary in the SCMP, the official was widely ridiculed and refuted by both the Beijing EPB and academic researchers.

But before we dismiss this story as a case of a ridiculous official trying to do anything to blame Beijing’s pollution on something other than poor environmental regulation of obvious major sources, let’s take a closer look at whether there is any merit to the claim.

First of all, how much does cooking really matter? The closest I’ve seen to an “official” source apportionment for Beijing’s PM2.5 pollution are numbers cited by Vice Mayor Hong Feng in a January 2013 interview. Cooking isn’t even included, leading me to believe that the Beijing EPB doesn’t see it as a primary culprit:


Here are those data in a pie chart:

The above data, like most citywide inventories I’ve seen, don’t include cooking. But is cooking generally omitted because it truly is insignificant, or simply because most researchers – wrongly – don’t even think about it? At least one researcher would argue the latter. Wang Yuesi, an atmospheric physics researcher at the Chinese Academy of Sciences, has claimed that cooking is responsible for 13% of Beijing’s PM2.5. A detailed breakdown of his numbers were presented at a Clean Air Asia conference earlier this year. Cooking here is shown in red (other sources are in comparable color to the above chart):

Wang Yuesi data on Beijing PM2.5 sources (left: Beijing; right: greater Beijing region)

I don’t know how many other researchers out there would validate this 13% number. Still, this is at least one data point to suggest that cooking is not entirely insignificant and (perhaps) should not be laughed off as quickly and easily as I did earlier this year.

Regardless of the exact contribution of cooking to Beijing’s overall pollution problem, this debate raises an important point that is sometimes forgotten in air quality discussion. When it comes to quality of life and health impacts, what matters is not citywide averages but what people are actually exposed to on a day-to-day basis. (In my work, I often argue that the 22% number thrown around for fraction of PM2.5 from motor vehicles is far smaller than the reality of exposure, since 3/4ths of Beijing’s population lives near a roadway.) Along these lines, my friend Rob Earley took issue with my WSJ comments and e-mailed me the following perspective:

While probably not a big contributor to ambient air pollution across the entire Beijing “airshed”, open-air charcoal fired BBQ is certainly a contributor to local pollution that can directly affect hundreds to thousands of people in areas of high BBQ intensity and high population intensity. As you know, I live directly upstairs from Gui Jie where there is no shortage of BBQing going on at night, and when the wind blows in the right direction, my clothes hanging in the balcony to dry will most definitely take on a smoky, lamby odour. My air purifier agrees that there is something coming through the window to get excited about. While I don’t have the resources to confirm this scientifically, there are research papers that suggest that BBQ smoke does contain significant particulate matter, aromatic compounds and traces of heavy metals. In areas such as gui jie where there are apartment buildings surrounding the BBQ area, there is definitely potential for hundreds of families to be exposed on a daily basis to local high levels of smoke in addition to ambient pollution. I do believe that a major principle of health effects from PM exposure has to do with local conditions – as we’ve discussed before, concentrations of PM are highest within 50 m of major roadways. I expect that PM concentrations would also be very high in areas that supply open-air charcoal BBQ on a regular basis.

In a follow-up, Rob noted that because it’s actually quite challenging to accurately estimate the pollution contributions from different sources in Beijing, people take advantage of the uncertainty to push certain political goals (maybe you have other reasons for wanting to crack down on barbecues) or to dodge responsibility. In the end, the proper solution is probably to go after all the sources you can think of. Although I believe the short and medium-term solutions to improve Beijing’s air quality are to tackle motor vehicles and coal-burning power plants and industrial facilities, that doesn’t mean that effectively controlling these will be sufficient to improve Beijing’s long-term air quality to world-class standards. California, which has notoriously struggled to improve air quality despite stringent emission standards, has regulations affecting a number of unexpected sources like wood-burning, lawnmowers, and, yes, even barbecues.

massive new state council air pollution control plan

Thursday, September 12th, 2013

China’s State Council today released a massive new air pollution control plan, the latest in a string of Chinese government actions (and promises of future actions) following January’s “airpocalypse.” This is certainly the highest profile and most wide-reaching plan we’ve seen so far, underscoring the attention being paid at the highest levels of government to improving air quality throughout the country.

I tweeted my thoughts tonight as I read the plan, but before I go to bed I’ll summarize a few highlights here.

First let me say that I have little expertise on topics beyond motor vehicles and ambient air quality monitoring. Some of the initial reporting (Reuters, WSJ) has focused on the plan’s announcements related to power generation, coal consumption, industrial emissions, etc. I’m not commenting on those here not because they aren’t important, but just because that’s not what I work on.

That having been said, here’s what really impresses me about the plan:

Major focus on regional coordination to improve air quality across broad air basins as opposed to working city-by-city. The three big regions mentioned repeatedly in the plan are the greater Beijing region (including Beijing, Tianjin, and Hebei), the Yangtze River Delta region (including Shanghai, Zhejiang, and Jiangsu), and the Pearl River Delta region in Guangdong. This is great news because, as I have noted, air pollution is absolutely a regional problem that requires regional solutions. Nice to see this being acknowledged by the State Council in such a foundational way.

– The plan establishes a system of binding ambient air quality improvement targets. I have previously written about how this is important for closing the loop between emissions and the air people are actually breathing, as well as for keeping officials accountable for environmental improvements that are tied to human health benefits. The specific targets in the plan are 10% reductions in PM10 concentrations for most cities, and 25%/20%/15% PM2.5 reduction goals for the greater BJ/YRD/PRD regions. The goals are all 2017 goals vs. 2012 baseline. There are some nice comments in the plan about the investigation and disciplining of officials who fail to meet the goals (though no specifics on penalties).

– Specific to motor vehicles, the plan reinforces the existing national fuel quality improvement timelines, but also establishes a new goal that China 5 gasoline and diesel (10ppm sulfur content) must be supplied to the three key regions by the end of 2015.

– The plan proposes massive scrappage goals for older, high polluting vehicles. China has hinted several times at goals to scrap all yellow-label vehicles (defined as Euro 0 gasoline and Euro 0, I, II diesel vehicles), but I’ve never seen such a clear goal codified before. The plan states that all YLVs nationwide should be scrapped by 2017. For the record, China had like 15 million yellow-label vehicles in 2011. That’s a huge number of vehicles to scrap. The plan also calls for “basically” scrapping all YLVs in the three key regions (5 million vehicles) by 2015, and scrapping all pre-2005 operational YLVs nationwide by 2015.

That’s the good news. Unfortunately, I wasn’t uniformly delighted by the plan. I am less than impressed by the following:

– I’m not sure why the plan sets PM10 reduction targets (as opposed to PM2.5) for some cities. PM2.5 is harder to control, but also more dangerous than PM2.5. China has new PM2.5 air quality standards and is completing a nationwide PM2.5 ambient air quality monitoring network, so why not jump straight to evaluation metrics based on PM2.5?

I’m deeply disappointed that the plan doesn’t call for any new vehicle emission standards. In this respect, the plan is much weaker than the plan Beijing released less than two weeks ago. Fuel quality improvements are critical because they enable more stringent standards to take effect. Scrappage programs are great, but they are most effective when the replacement vehicles are as clean as possible. Why would the State Council release such a comprehensive plan that doesn’t include any mention of upgrading vehicle emission standards? It is a strange and glaring omission to me.

Final note: here’s what I wish it said about vehicle emission standards: “taking advantage of the upgraded fuel supplies, China VI vehicle emission standards will be implemented in the three key regions in 2015, and nationwide in 2018.”

beijing’s comprehensive new motor vehicle emission control plans

Friday, September 6th, 2013

Earlier this week, Beijing’s government “declared war” (宣战) on PM2.5, releasing its most aggressive, detailed plan to date to reduce emissions and improve air quality. The overall goal of the plan is to reduce Beijing’s PM2.5 concentration about 25% from 2012 levels by 2017. The targets vary by district, but the overall average for the city – and the target for the most densely populated areas – is 60 ug/m3. Achieving this target would represent dramatic progress for the city, though even at 60 ug/m3 Beijing’s air quality would still be nearly double China’s ambient air quality annual standard (35 ug/m3).

Still, the plan is impressive in its breadth, specificity, and detailed assignment of responsibility. For each of the 84 separate measures described, the leading agencies – and even name of the person(s) on the hook – are mentioned.

Several of the key features of the plan have already been summarized by the media (e.g. Reuters, Xinhua, CRI). But I thought it would be worthwhile to translate and take a closer look at some of the specific actions related to motor vehicle emission control (Section 3 of the plan). The 22 measures described (#21-42) represent a truly comprehensive and world class approach to controlling air pollution from cars, buses, and trucks in the city. Beijing already has mainland China’s highest fuel quality (10 ppm S) and most stringent tailpipe emission standards (China V). Completing the following plan would cement Beijing’s position not just as a leader within China but as one of the world’s leading cities in terms of motor vehicle emission control.

Selected vehicle emission control measures from Beijing’s 2013-2017 Clean Air Action Plan:

#21: Control total vehicle population in the city to less than 6 million by the end of 2017. Given that the population of vehicles in Beijing already well exceeds 5 million, this will almost certainly mean reducing the current monthly new vehicle quota of 20,000.

#22: Reduce fuel consumption in the city by >5% in 2017 as compared to 2012, primarily through the promotion of new energy vehicles, small vehicles, and reducing overall vehicle use.

#23: Increase the cost of vehicle use through various measures, including progressive parking pricing and a congestion charge (though it should be noted that that the plan only commits to researching this, not to implementing it).

#24: Restrict vehicle use by time and location, including more strict controls on vehicles registered outside Beijing. Beijing already has such restrictions, but they will be expanded. For example, beginning in 2014, only China III and higher certified vehicles will be eligible to receive permits to regularly enter the 6th ring road. After 2015, only China IV and higher light-duty vehicles will be eligible for permits to enter the city, and yellow-label trucks (China II and older) will be banned altogether.

#26: Upgrade vehicle emission standards for on-road vehicles and off-road engines.

  • By the end of 2014, all new heavy-duty diesel vehicles should meet the China V standard, while all new heavy-duty diesel vehicles used in the city center should be equipped with DPFs. In addition, 100 public buses should meet the China VI standard (pilot), and Beijing EPB should begin research on the “Beijing 6” standards for LDVs.
  • Beginning in 2015, all off-road equipment must meet the Tier 4 standard or better.
  • By 2015, Beijing EPB will complete an ORVR standard and implementation plan for gasoline vehicles.
  • Strive to implement the China VI standards in 2016.

#27: Improve fuel quality by establishing a China 6 standard for local fuel quality and strive to implement it in 2016. Beijing has the potential to surpass Europe (currently at Euro 5) in this regard.

#28: Scrap one million older vehicles, including all yellow-label vehicles by 2015. Beginning 2014, preferentially support the replacement of vehicles with hybrid and energy-saving vehicles with displacement <1.6 L. This would presumably be an extension/expansion of Beijing’s existing scrappage programs, which are already China’s most successful. (Latest stats: Beijing scrapped nearly 150,000 vehicles in the first half of 2013.)

#29-37: Incredibly specific targets for introducing clean and alternative fuel vehicles (electric, hybrid, natural gas, etc.) in the public bus, taxi, long-distance bus, municipal service vehicles, freight, and low-speed vehicle fleets.

#38: Strive to have 200,000 new energy and clean energy vehicles in the city by the end of 2017.

#41: Strengthen in-use vehicle supervision and fuel quality compliance, including greatly expanding the number of random emissions inspections, building a full remote sensing network with 150 sets of equipment by 2016, and increasing the number of fuel quality checks including vapor recovery system evaluations.

#42: Set energy reduction standards for the transportation sector, including fuel consumption standards for freight vehicles. This will be interesting as it’s unclear what authority Beijing has to set or enforce such standards.

It’s really quite an impressive list. In many cases, there is significant additional detail beyond what I’ve described above, plus there are additional measures on public transit that I didn’t include here.

So, will it work? We’ll see. In any case, at this point it’s hard to imagine anything else Beijing could be doing beyond what’s in this plan to control emissions within its borders. Unfortunately, much of Beijing’s pollution is regional in nature, drifting in from the surrounding provinces. Hopefully, Beijing’s aggressive action demonstrated in this plan will spurn equivalent aggressive, comprehensive action at the regional and national levels.

timeline of china’s official resonses to recent severe pollution

Thursday, January 24th, 2013

List last updated Beijing time 4/1/13 6:00am

In the fall of 2011, public discontent over a series of poor air quality episodes in Beijing ultimately led to an impressive series of actions by China’s national Ministry of Environmental Protection (MEP) and the Beijing Environmental Protection Bureau (EPB). It took a few months, but by February 2012, China had issued a revision to the ambient air quality standards, a new definition of the Air Quality Index, and by the end of the year, had completed and began operating a network of real-time PM2.5 monitors in 74 cities through the country.

So if the “wins” of the fall of 2011 were great strides towards monitoring and reporting, then here’s to hoping that this most recent episode of crazy bad air will turn into progress on actually reducing emissions themselves.

To help track the progress, I’m creating here a timeline of “official” Chinese government responses to date on the recent severe pollution in Beijing and many other cities across China. This includes major announcements I have seen from MEP and the Beijing EPB; if anyone knows of other key announcements I’ve missed, from other ministries, or from other cities like Shanghai, let me know and I’d be happy to add them. I will be curious to see where this list goes in the coming months.

Note 1: Major announcements shown in bold.
Note 2: MEP often back-dates announcements; the dates shown here are the “official” release dates, even though often the announcements don’t go up publicly until a week (or more) later.

1/12: “Crazy bad” air hits Beijing and other cities across China, sparking unprecedented reaction from domestic and international media and the general public
1/14: MEP issues its first official response, “Notice requiring each area to conscientiously conduct air quality monitoring and early warnings on heavy pollution days”  环境保护部发出通知要求各地认真做好重污染天气条件下空气质量监测预警工作
1/14: MEP issues a draft arsenic pollution prevention technical standard for public comment 关于征求《砷污染防治技术政策》(征求意见稿)意见的函
1/15: MEP and Beijing EPB issue a brief evaluation and explanation of the pollution, “Beiing EPB analysis of the extended severe pollution – large emissions the fundamental reason” 北京市环保局分析持续严重污染原因 排放量大是根本原因
1/15: Vice Premier Li Keqiang issues a brief and fairly anodyne comment pledging action: 李克强谈空气污染治理问题:我们必须有所作为
1/17: MEP issues the second round draft light-duty vehicle China 5 tailpipe emission standard for public comment 关于征求《轻型汽车污染物排放限值及测量方法(中国第五阶段)》(二次征求意见稿)意见的函
1/17: MEP issues a draft mercury pollution prevention technical standard for public comment 关于征求《汞污染防治技术政策》(征求意见稿)意见的函
1/18: Beijing EPB issues a super strange announcement warning websites not to claim official approval to report air quality numbers: 关于对部分社会化监测机构冒用我局名义进行虚假宣传有关说明的公告
1/19: Beijing issues a major new set of comprehensive regulations on air pollution prevention and control: 《北京市大气污染防治条例(草案送审稿)
1/23: Beijing’s mayor Wang Anshun makes a speech in the context of the Beijing People’s Congress with some numbers to back up the new regs (not sure the best link for this; perhaps this work report 《政府工作报告》解读:展望·2013年的北京)
1/23: Beijing issues new tailpipe emissions equivalent to Euro 5/V for gasoline cars and municipal diesel vehicles, implementation starts almost immediately on 2/1: 北京2月1日起执行第五阶段机动车排放标准
1/24: MEP Minister Zhou Shengxian holds National Environmental Protection Work meeting, pledges some actions 全国环境保护工作会议在京召开
1/24: Influential Tsinghua professor says China’s Clean Air Act revisions moving forward (I will update official link when I find one)  机动车污染防治条款浮出水面 环保不达标召回
1/25: MEP releases a notice about the implementation of Stage II emission limits for gasoline non-road mobile machinery: 关于实施国家第二阶段非道路移动机械用小型点燃式非手持式发动机排放标准的公告 (note: I can’t figure out how this announcement changes anything about existing schedule)
2/4: State Council issues roadmap for diesel and gasoline fuel quality improvement: 温家宝主持召开国务院常务会议 – 决定加快油品质量升级
2/6: MEP issues draft for public comment of “Atmospheric Fine Particle Pollution Prevention and Control Technology Policy (trial)” 环境空气细颗粒物污染防治技术政策(试行)
2/7: SAC issues new diesel fuel quality standard (China IV): GB19147-2013
2/16: MEP issues statement about air quality during the Chinese New Year holiday: 环境保护部通报春节期间我国部分城市空气质量状况
2/16: MEP approves Tsinghua University to build an air pollution control laboratory 关于同意建设国家环境保护大气复合污染来源与控制重点实验室的复函
2/17: MEP issues 12th Five-Year Plan for Environmental Standards: 关于印发《国家环境保护标准“十二五”发展规划》的通知
2/26: MEP releases two new draft standards on air quality monitoring, including monitor placement, for public comment: 关于征求《环境空气质量评价技术规范(试行)》等两项国家环境保护标准意见的函
3/15: Beijing releases the 2013 Clean Air Action Plan 我市发布实施2013年清洁空气行动计划
3/22: MEP releases a notice about “Implementation plan for stage II monitoring for ambient air quality standards” 关于印发《空气质量新标准第二阶段监测实施方案》的通知
3/29: Beijing and Tianjin sign an agreement to work together on improving air quality 京津两市签署协议加强环保合作共同致力于改善环境质量
3/29: News reports suggest that Beijing will spend 100 billion RMB to combat air pollution as part of its previously released 2013清洁空气行动计划

I will try to update this from time to time. Note that not all of these are direct responses to the pollution episodes; for example, the draft standards have been under development for months if not years. I don’t know whether or not the decision to release them for public comment now is linked to the recent pollution episode…

seeking solutions to china’s air pollution crisis

Friday, January 18th, 2013

A version of this essay, in Chinese, first appeared on the New York Times’ Chinese website.

Over the past week, hundreds of cities across China experienced dangerous spikes in air pollution levels. With air quality degrading to 20 or even 30 times worse than what is deemed safe by the World Health Organization (WHO), even our language strained to describe it (what can be worse than “hazardous”?). As visibility dropped to nearly zero and hospital admissions surged, the Chinese public began demanding both explanations and actions to prevent similar episodes in the future.

Unfortunately, extreme pollution events are common in China – especially in Beijing. This week’s pollution was notable for being the worst in recent memory, but the pollution accumulation spike was not unique – and next time it may even be worse. Even more important from a long-term health perspective, annual average air pollution levels in many cities in China remain unacceptably high. Until the government succeeds in implementing comprehensive policies requiring deep and permanent emissions reductions throughout the country, China will continue to struggle with air pollution for the foreseeable future. Fortunately, the policy and technology solutions to solving China’s air pollution crisis are well-known. Even better: these solutions will save millions of lives and can be implemented without sacrificing economic growth.

Causes of air pollution
China’s rapidly increasing numbers of coal-burning power plants, inefficient industrial facilities, and motor vehicles burning dirty fuel produce an enormous volume of air pollution every day. Pollutants directly emitted by these sources react with each other in the chemical soup that is the atmosphere, producing new types of “secondary” pollution including health-damaging ground-level ozone. This pollution is then transported through the atmosphere by prevailing meteorological conditions. When winds are stagnating – as was the case last weekend throughout much of eastern China – air pollution can accumulate rapidly. Geography can further complicate the pollution story. Cities bounded on two or more sides by mountains – such as Beijing and Los Angeles – are even more susceptible to severe pollution episodes. In Beijing’s case, winds blowing gently from the south carry air pollution from across central and northern China and trap it against the mountains to the north and west of the city.

Air pollution is regional
Because pollutants travel easily in the atmosphere (and some pollution sources, like vehicles, travel themselves), air pollution is fundamentally a regional problem, requiring regional or – even better – national solutions. Scientists have estimated that between one-third to two-thirds of Beijing’s pollution is caused by emissions in the surrounding provinces. Beijing’s government has implemented dramatic and impressive measures over the past decade to reduce pollution emissions within its boundaries; for example, the city has nearly eliminated coal-burning, implemented the most stringent vehicle emissions and fuel quality standards in the country, scrapped hundreds of thousands of high-emitting cars and trucks, and forced major industrial plants to relocate. However, pollution level spikes in the city continue to occur throughout the year, and average air pollution levels are far from meeting even China’s air quality standards. Though cities undoubtedly have a critical role to play in reducing emissions in China, air pollution cannot be solved exclusively at the municipal level.

Neither monitoring and reporting nor temporary policies are enough
The Chinese government has reacted to the recent, severe pollution episode by pledging to improve pollution data accuracy and transparency, and by implementing short-term, “emergency” pollution reduction policies like restricting government car use and temporarily halting factory production. Similar (though even more draconian) temporary policies were proven to be an effective regional air quality improvement strategy during the 2008 Beijing Olympic Games. However, although these temporary policies may have some impact on reducing the severity of short-term pollution level spikes, they will do little to address the elevated day-to-day average pollution levels that are killing hundreds of thousands of people in China every year.

As for data transparency improvements, these are important and welcome steps, particularly the recent launching of real-time air pollution reporting for 74 cities in China and pledges to improve early, public warning systems during hazardous pollution conditions. However, monitoring and reporting are fundamentally only descriptions of the problem, not solutions themselves.

Solutions: deep and permanent cuts
The fundamental solution to China’s air pollution crisis is the rapid introduction of deep, permanent emissions reduction policies for all sources, especially power plants, industrial factories, and motor vehicles. For such policies to succeed, many of the necessary steps – for example, confronting entrenched state-owned enterprises and significantly expanding and empowering China’s national environmental protection authority – will not be easy. But only through long-term reductions in the total volume of air pollution produced in the country will pollution level spikes be eliminated, and average air quality begin to improve in all Chinese cities.

Consider the case of motor vehicle emission control. With China now the global leader in automobile production and sales, emissions from cars, buses, and trucks are a large and growing – and sometimes overlooked – source of air pollution. Of particular concern are long-distance diesel trucks belching black smoke as they travel regionally between factories, distribution centers, and cities. China’s Ministry of Environmental Protection has already issued a policy, “China IV,” that aims to reduce dangerous particulate matter emissions from new trucks by 80 percent. However, MEP has been forced to delay nationwide implementation of these standards twice already – for a total of two and a half years – because the quality of diesel fuel produced by China’s state-owned refineries significantly lags behind what is required for the new truck technologies to function properly. Furthermore, immediate improvements in China’s nationwide fuel quality will not just enable the introduction of “China IV” trucks. They will also facilitate the introduction of future “China VI” vehicles requiring tailpipe filters which eliminate nearly all particle emissions.

Even once this and other standards do go into effect, the Chinese government faces severe capacity shortages to properly enforce them. In the United States, the Environmental Protection Agency employs some 18,000 government officials. How many are there in China’s Ministry of Environmental Protection? Just a few hundred.

Economic growth can continue
In the 1970s, the United States faced an air pollution crisis not so different from that of China today. Cities like Los Angeles regularly experienced both short-term spikes and dangerously elevated average levels of air pollution. But stringent, wide-reaching, permanent control programs implemented for a variety of sources in the United States have produced dramatic results. From 1980 to 2010, emissions of major air pollutants in the United States were cut by over half – even as GDP more than doubled. And because the societal costs of air pollution – hospital bills, reduced productivity and missed work days due to illness, premature death, agricultural loss, and more – can be exceptionally high, analyses in the US have regularly shown that pollution reduction policies deliver total societal benefits far outweighing their costs – often by a factor of five to ten or even higher.

China is no different. The enormous, current economic costs from the health burdens of air pollution in China have been estimated to total at least 1.2 percent of GDP. And this doesn’t even factor in additional “hidden” losses from, for example, damage to China’s international image. China’s past three decades of remarkable development have produced enormous gains for average citizens. But they have also produced dramatic increases in emissions of air pollutants. Fortunately, experience throughout the developed world proves that economic growth can thrive even while air pollution is reduced. This week, China’s Vice Premier Li Keqiang responded to China’s severe pollution with pledges of increased government action. Only if this action includes critical steps such as deep, permanent cuts in emissions from all sources, strong enabling policies like improvements in fuel quality, and broad expansion of China’s environmental authorities, will China’s days of “crazy bad” air finally be gone forever.

turning the conversation about Beijing’s air pollution toward solutions

Tuesday, January 15th, 2013

This post originally appeared on the ICCT Staff Blog.

Over the past weekend, poor meteorological conditions contributed to a severe accumulation of air pollution in Beijing and hundreds of other cities in northern and eastern China. The extreme pollution was the worst in recent memory, yielding hundreds of media reports both within China and around the world. In addition, tens of millions took to Twitter and China’s Twitter-like service, Weibo, to post their thoughts and complaints. Unfortunately, such extreme pollution accumulation episodes are common in Beijing. And even when meteorological conditions are good, average pollution levels in Beijing are still unacceptably high. Until China takes critical steps towards reducing emissions, poor average air quality and occasional “crazy bad” episodes will continue.

Vehicles are a critical source to control
Vehicles are typically by far the largest source of human exposure to air pollution in densely packed urban areas. Plus, the contribution of vehicle emissions to air pollution in China is increasing as the population of motor vehicles in Beijing and around China continues to grow rapidly. Implementing stringent controls to mitigate the pollution impacts of China’s motor vehicles must be a key priority in parallel with controlling other sources such as factories and power plants.

Moreover, such action needs to take place at the national level. Because vehicles (especially trucks and long-distance buses) travel in and out of cities, only stringent national-level regulations can ensure that all vehicles are controlled effectively no matter where they travel. In recent years, Beijing has made a series of impressive steps towards controlling pollution within its own boundaries (e.g. the most stringent vehicle standards in the country, the cleanest fuel quality standards in the country, scrapping >500,000 old polluting vehicles over the past two years, and more). However, the city still struggles to improve air quality because perhaps 34%-70% of Beijing’s pollution is regional, coming from dirty vehicles and industrial sources polluting in the surrounding provinces.

Short-term actions to control motor vehicle emissions in China
Two simple steps could make a huge and near-term difference in improving air quality in Beijing and throughout China, while simultaneously demonstrating the new Chinese government’s commitment to reducing pollution emissions:

1) Immediately issue new fuel quality standards with supporting fiscal policies to reduce nationwide diesel sulfur levels to below 10 parts-per-million (ppm). Because high sulfur levels in fuel can poison advanced emission control technologies, improving fuel quality, especially reducing sulfur levels, is a critical prerequisite to introducing more stringent vehicle tailpipe emission standards. In 2011, China’s State Council announced that preferential fiscal policies would be utilized to encourage the supply of higher quality fuels nationwide. However, these fiscal policies have not yet been issued; a new fuel quality standard is stalled in the review phase; and nationwide diesel fuel sulfur levels continue to stagnate at unacceptable levels of 350ppm or higher. Resolving the fuel quality issue is a critical step to facilitate continued progress in vehicle emission control in China.

2) Ensure that the China IV truck and bus emission standards are implemented this year without further delays. China’s next stage nationwide tailpipe emission standard for trucks and buses, called “China IV” (equivalent to “Euro IV”), aims to cut emissions of PM and NOx from diesel vehicles by 80% and 30%, respectively. However, because these vehicles need to be fueled with higher quality fuel which is not yet supplied nationwide, MEP has twice delayed the introduction of these standards across China. The current implementation date is July 1, 2013. In parallel with resolving the fuel quality issue, China should commit to introducing these standards without any additional delays.

Medium and long-term action to control emissions from motor vehicles
The aforementioned short-term, immediate actions will not be enough to solve China’s long-term motor vehicle emissions problems. Last month, China laid out a number of impressive medium-to-long-term regional air quality improvement actions in its “12th Five-Year Plan for Air Pollution Prevention and Control in Key Regions.” While the plans outlined in the document represent significant progress, the plan does not call for the most important step China can make towards long-term control of vehicle emissions: establishing a clear nationwide timeline for the introduction of global best-practice “China VI/Euro VI” vehicle tailpipe emission standards. Only with the introduction of these standards will diesel trucks and buses – some of the most polluting vehicles on the road – be required to install particulate filters to reduce >99% of PM2.5 particle emissions. Filters belong on cars, not people.

Monitoring and reporting: a recent success story, but only the first steps
In the fall of 2011, public outcry over a series of heavy pollution episodes in Beijing was fanned by social media into enormous public pressure on Chinese authorities to respond. They did. In February 2012, China’s Ministry of Environmental Protection (MEP) issued two major new regulations: a revision to the ambient air quality standards to include PM2.5, and a new definition of China’s Air Quality Index. By the end of the year, China had completed and began operating a network of real-time PM2.5 monitors in 74 cities through the country. The Chinese government deserves praise for these important steps towards air pollution data transparency.

However, air quality monitoring and reporting are only first steps. Now the challenge is how to achieve rapid and significant emissions reductions in order to improve urban air quality. The above three steps – rapid improvement of fuel quality, introduction of China IV standards for trucks and buses this year, and establishment of a clear timeline for early introduction of China VI – will make huge differences in reducing toxic air pollution in Beijing and throughout China. In fall 2011, the public debate led directly to new standards on air quality monitoring and reporting. It’s time now to turn the current pressure towards the more fundamental issues of how and when to cut emissions themselves.

demystifying air quality numbers

Sunday, January 13th, 2013

There are lots of numbers used to describe air quality these days in China. This post is intended as a glossary to demystify the different numbers currently used by various sources.

Concentration: The most direct way to report air pollution would be the concentration of a given pollutant in the air. This is straight-forward science and measurement. Example: PM2.5 concentration is 950 micrograms per cubic meter (ug/m^3).

Although concentration is straightforward scientifically, there are a couple of problems with it from a public outreach perspective. First, not everyone understands what concentration is, or has context for what the numbers mean. Second, it’s difficult to compare different pollutants to each other, since each pollutant affects people differently depending on concentration. Therefore, concentrations are commonly normalized to some scale, on which multiple pollutants can be compared together and a single “score” covering multiple pollutants given to a city.

Confusingly, there are currently three such scales used to describe Chinese air quality: the US Air Quality Index (AQI), the current/outgoing Chinese Air Pollution Index (空气污染指数, API), and the current/future Chinese Air Quality Index (空气质量指数, AQI). Here are the technical details of each one:

US AQI: In the United States, concentrations are converted to the “Air Quality Index” using breakpoints defined in 40 CFR 58 Subpart G. (Edit 1/13/13: The EPA has just revised these breakpoints, though it hasn’t posted to the CFR yet. New breakpoints shown here and in the graph below.)

Note: the US does not define an AQI above 500. On, if you use the AQI->concentration calculator and input an AQI above 500, it gives an error message.

This means that AQIs reported by the Embassy above 500 are not in accordance with US regulations. My guess is that they linearly projected using the same slope as the 400 –> 500 line.

China API: China’s current but outgoing system of API uses breakpoints described in an old post of mine here. This is officially the current system in place nationwide, though it does not include PM2.5 or ozone.

China AQI: In February 2012 (regulation HJ 633—2012), China defined a new air quality index that includes PM2.5 and ozone. It doesn’t take effect nationwide until 2016, but Beijing and many other cities have already adopted it. The China AQI breakpoints are here:

Note that the Chinese system also does not define an index above 500. This is why the data reported by the BMEMC rail at 500 for AQI. I don’t think they project as the Embassy does.

Let’s do a quick comparison of the PM2.5 cutpoints in the US and in China:

1) The US is more strict at low concentrations.
2) The systems are identical above a concentration of 150 (AQI of 200).
3) Neither system is linear, which is annoying and non-intuitive.
4) It is also very annoying that the numbers are so close (as opposed to a 1-10 index, for example). This means it is very easy to confuse AQI and concentration.

– Concentration is the most accurate way of describing air pollution, but isn’t good for public awareness and comparing multiple pollutants.
– Both the US and China use AQI systems. Both systems go from 0-500, and are not technically defined above 500.
– The US and Chinese systems are identical above an index value of 200 (PM2.5 concentration of 150), but slightly different below this level.
– Because the systems aren’t identical and have different slopes, you have to be very careful when saying something like “PM2.5 is 150.” The meaning of this statement is different depending on if you mean concentration OR US AQI OR Chinese AQI.

Confused yet?

china’s real-time air pollution reporting gaining traction

Sunday, January 13th, 2013

The lead news story on Sina right now is the intense pollution in Beijing and other cities in eastern China. The story is depressing, of course, but I’m encouraged that Sina is reporting numbers from the new Beijing Municipal Environmental Monitoring Center’s real-time reporting system. In this story, they note a maximum PM2.5 concentration reading of 950 ug/m3 in Tongzhou (also here, with graph.) A similar data point making the rounds on weibo and some news outlets is Xizhimen’s maximum PM10 level of 993 ug/m3, again reported based on Beijing’s own monitoring.

Why is this encouraging? Because it represents a much-needed shift away from reporting air quality data from the US Embassy – with all its political and data accuracy concerns – and towards China “owning” its own monitoring and reporting system.