BeijingAirblog.com

Looking at the graph below, we can see the daily API values for Beijing in 2008 in blue, and a black trend line based on a moving average over 10 days. The first half of the year was similar to what we have seen over the past years, with an average of around 100, with severe peaks above that. However, from June the trend was downwards, reflecting the success of the efforts for clean air during the Olympic Games. The trendline even dipped under the 50 line, which is considered acceptable air quality, around mid-August.

Unfortunately the trend since August has been upwards again, as a result of lifting the temporary restrictions (traffic, industry). Let’s look at the monthly averages:

• August: 56
• September: 57
• October: 75
• November: 80
• December: 98
• January: 82
• February: 90 (first 6 days)

So despite the relatively good air of the summer of 2008, December seemed back to normal (read: very unhealthy). The yearly average API for 2008 stood at 87, which is certainly significantly better than the values around 100 we have been seeing over the last few years.

Of course this is all based on officially reported data. The issue of their reliability remains; as we have discussed last year, there is something strange about the absence of API values of 101 and 102, which statistically is extremely unlikely.

Of course this is related to the concept of ’blue sky days’ which are counted as having an API of 100 or less, and which are an important policy performance indicator. So imagine the pressure on man and machine when the value comes out as 101 or 102.. It Just Does Not Happen, and some things never change.

On 20 Sep the Olympic/Paralympic traffic restrictions (odd/even) were lifted, and then something remarkable happened: people started to talk about how nice it had been with less cars on the roads, and according to a Greenpeace poll (China Daily), even 54% of car owners wanted some sort of restrictions to stay in place. On 11 Oct a 6 month experiment has started that takes 20% of the cars off the roads each weekday. I think the most important result of this could be that most car driving people are now forced to look into alternative means of transport (subway, bus, bike, car pooling..)  and that they realise that those alternatives actually make a lot of sense, and hopefully, use them more often than once a week. Below a graph that shows the API of past months, with those 2 dates.

If we look at monthly averages, keeping in mind that the yearly average has been around 100 over the past years, it is clear that the past months have been exceptional:

• August: 56
• September: 57
• October: 75
• November (incomplete): 88

From the start of 2008 until 17 Nov, we are looking at an average API of 87 which is better than the previous years, but still no reason to celebrate. We are still often having bad days with API of over 100 which is by all standards unhealthy.

Earlier this month i attended a clean air conference in Beijing, organised by Tsinghua University with participants from MEP and USA-EPA. I was quite impressed to hear about how they have been working years in advance on a master plan to limit the air pollution during the Olympics. It all came down to a ‘regional approach’, in which the surrounding provinces were involved in the efforts, because it has been proven that a large portion of the fine dust, and other pollutants, does not originate in Beijing. The provincial officials seems a bit to triumphant; but i have to give them the credit that the relatively-clean air Olympics were more than just a bit of luck- let’s hope that the lessons learnt will be kept into practice.

As reported below, the traffic measures started on 20 July, so let’s have a look at the air quality since then. As you can see on the below graph, the API values since 20 July have gone up each day since 20 July (blue line is for Beijing). This is very unfortunate, but it shows that the traffic reductions have only a limited effect on the air quality, as discussed in the previous post. Of course we can be sure that without the reductions, the pollution would have been even worse; but taking half of the cars off the road does not solve the problem.

The pink dotted line is for Tianjin, a city 150km East from Beijing, where no traffic restrictions have been imposed as far as i know. We see that the trend is very similar, and actually the values for Beijing and Tianjin are also quite close, with Tianjin being generally a little better than Beijing, except for the last few days, where the upward trend is more strong in Tianjin, suggesting that the traffic restrictions in Beijing do help to keep the values in Beijing down, despite the upward trend- this is speculation of course. The experiment last year with 4 days of similar traffic restrictions in Beijing were not a success either, as shown in this post. It simply has not rained for a couple of days.

In the mean time the BeijingAirBlog is celebrating its 10,000th visitor, mainly due to a boost from referrals from CNN over the last couple of days, but i did not manage to find the link on their site.

The Wall Street Journal has a nice graph of something i have been pointing out since November 2007, and when they put this in front of Chinese officials, the spokesman of Beijing-EPB claimed it shows ‘the ability of government measures to head off short-term spikes in pollution’…

Yesterday the reduced traffic measures kicked in, and i found myself in a traffic jam on the second ringroad on a Sunday around noon, with supposedly 30% less cars on the road, but 1 of the 3 lanes left empty because of its ‘Olympic’ status. The main aim here is to get the athletes and spectators to the venues on time it seems.

I tend to agree with professor Rahn (on this wired.com article), who says that these traffic measures will have very limited effects on the air quality (less than 10%): the main actor on the air pollution stage is the weather. On cloud seeding, he adds:

“They cannot depend on weather modification. Nature is bigger and stronger than the Chinese people and rockets,” Rahn said. “The west has known this for 50 years but China is in the stage of development where they think science and technology can do everything.”

So my best bet is still: China will move heaven and earth to make it rain on 7 August, and get a clear sky when the camera’s start rolling on 8 August and the opening ceremony. But in fact the camera’s are already rolling, and it is just impossible to avoid some bad (and very bad) days during the following 6 weeks. The authorities have been working hard on reducing the sources of the worst air pollution, but as an environmental problem, it takes more than a local effort to change the trend, and let’s hope the efforts will not be abandoned after the Games are over and the cameras stop rolling.

The weather has been quite wet recently in Beijing, and it’s hard to tell if that fog is just humidity or smog… The average API over the first 15 days of July is only 73, well below the average value of 100, so it seems our daily portion of rain, and a bit of wind, clears the air quite well. We had the same monthly average in February which was an exceptionally clear month (see below).

However, as i have reported on many occasions before, the correctness of official data from the Beijing Environmental Protection Bureau, and the Ministry of Environmental Protection, may be questioned (in addition to the dubious changes in monitoring stations). BBC measured PM10 values last week of more than double the officially reported values as reported in this article, but in their enthusiasm they compared the reported API directly with their measurements of PM10 (microgram per cubic meter). API and PM10 are not the same as i explain here. So in fact the reported values are up to 50% higher than shown in their graph, and much closer to their own measurements. By coincidence this makes it look more spectacular of course… For example the API value of 8 July is 98, which corresponds to a PM10 of slightly less than 150, but in the BBC graph it is shown as 98 on the PM10 scale.

In addition, they did not mention how/where these measurements where made, which makes it rather a scientifically unsound claim if you ask me. Although i do not doubt that the actual levels could be much higher than officially reported, i wonder if a sample measurement of a presumably handheld device on one spot can give a value truly representing the city situation. I am sure more journalists will be making their own measurements, which can give correct values for the air at a particular place at a particular time, but should not be compared to the officially reported API.

Today 27 May 2008 Beijing’s API is 463, the worst of this year so far.

People often ask me if i think the situation is getting any better, but unfortunately i don’t think it is. Let’s look at the numbers for this year, keeping in mind that the yearly average API over the last years was nearly constant, around 100.

Average API jan-may 2008: 99.5 (so not better or worse than previous years)
Average API jan 2008: 83
Average API feb 2008: 73
Average API mar 2008: 109
Average API apr 2008: 103
Average API may 2008: 131 (until 27th)

So as described below, the months of January and February gave us some hope that the situation was improving, but April and May are showing us that’s too optimistic.

I used to collect the daily API values from the MEP/SEPA website, but it seems their list function at the bottom of the page is not working anymore, what a pity (or can somebody tell me what i am doing wrong?). So i had to go to the Beijing EPB website and manually retrieve all daily values… below a sample of today, showing several stations went off the scale.

Apologies for not posting recently and not answering comments/questions, busy here with newborn baby!

Over the last 3 months it has been tempting to think that the air quality in Beijing was actually improving since the start of the year, but the last weeks have been as bad as we are used to. The graph below shows the daily API values in blue, with a black trend line of 10-day moving average, which stays below the 100 (yearly average) for roughly the first 10 weeks of 2008. 71 so-called ‘blue sky days’ out of 98; that is 72% which is a bit higher than the 67% of last year. A stroke of good luck, plus the effect of less industrial activity around Lunar New Year? On 18 March the first sand storm hit Beijing, and the API went up to 304.

You can see in this graph that February was an exceptionally good month, with an average API of only 73, well below the yearly average of 100. This article reports that 10 key polluting factories in Beijing, Hebei and Tianjin have already been closed to improve the air quality ahead of the Olympic games, and the provinces of Shandong, Shanxi and Inner Mongolia are also being involved in the efforts.

Before we get to optimistic, let’s remember the monitoring station shift described on this blog before, which will make it easier to get lower API values without actually getting better air quality. BOCOG environmental director responded to this story with the statement that the stations ‘were not moved’, but as we have demonstrated, the list of 27 stations simply has changed. In fact it is not so complicated for anyone who wishes to see for themselves; an effort this person obviously did not make. According to China Daily, 66% of Beijingers recently polled about the air quality, think it has improved. Probably the poll took place in February, a stroke of luck.

Beijing is seeing an unusually long series of ‘blue sky days’, today is the 8th one in a row (SEPA API 21-28 Jan), but you may have noticed the air smells of sulphur more than usual. Indeed for the last 4 days (25-28 Jan) SEPA is reporting SO2 as the main pollutant. Strange after China Daily (17 Nov 2007) reported the end of coal heating in Beijing, and since EURO 4 fuel standards were introduced from the start of this year.

Today’s API is 66 only, much lower than the last 3 days, probably because of the snow that cleared out the air last night. Interesting to note however that the main polluting substance was not PM10 (fine dust) as it is 99% of the time, but SO2 (sulphur dioxide) first time this year, the main cause of acid rain as far as i know, and emitted by burning not-so-clean fossil fuels (coal and petroleum products). 

This is also a reminder that although Beijing’s main problem is PM10, the other common pollutants (SO2, NOx, CO,O3) are probably also at alarming levels, but just not as much in view as the PM10 because that is the worst problem. For example i wouldn’t know where to find daily figures of SO2 measurements; it seems they are not published, only the general API is available.

Another interesting observation from today’s list of major Chinese cities; about half of the cities are reporting SO2 as main pollutant (the other half reports PM10 as usual). This has most probably something to do with the cold weather and the need to burn more fossil fuels for heating, and their high sulphur content. 

Yesterday 13 January 2008 Miyun Reservoir reported an API of 13, lowest of the 27 stations in Beijing (the lowest value this year was 12, also in Miyun on 1 Jan). Not so surprising as you can see from the below picture of the reservoir i took yesterday; difficult to consider this nature area as a ‘neighbourhood’ of our city. People in the south of Beijing (Daxing) had to cope with an API of 68 yesterday.