中国与世界,环境危机大家谈

china and the world discuss the environment

  • linkedin group
  • sini weibo
  • facebook
  • twitter
envelope

注册订阅每周免费邮件
Sign up for email updates


文章 Articles

US cities suffer impact of downwind Chinese air pollution

Tom Levitt

Readinch

Ozone and mercury pollution from Chinese industry is contributing to worsening air quality in west coast states like California.

article image

Satellite image of air pollution spreading out over eastern China and winding a course across the East China Sea, past the Korean Peninsula and northeastwards toward Japan (Image by NASA).

 

Around 9,000 feet up, on a remote mountaintop in the state of Oregon, a group of researchers are on the lookout. It´s not planes or wildlife they are tracking but pollution clouds.

The monitoring site is run by Dan Jaffe, professor of atmospheric and environmental chemistry at the University of Washington-Bothell, who has spent the past 16 years trying to understand how pollution is carried around the world. Specifically, how a growing amount of pollution from China and the rest of Asia is being carried over the Pacific and dumped on the west coast of the US.

The impact is a fairly regular number of air pollution violations in US cities, directly attributed to pollution that originated in Asia.

With stricter controls in US cities on pollution, interest in Jaffe's team's work is growing, both from government officials and industry, which itself is under pressure to reduce the most harmful pollutants.

What's more, major plans to scale-up the export of US coal to China are being questioned due to concerns it could contribute to worsening air pollution both at home and abroad.

Air pollution knows no boundaries

As Jaffe explains, the commonly heard phase “air pollution knows no boundaries” takes on a new meaning when we start to understand how pollution is travelling around the globe. The pollutants pumped out into the air never disappear into thin air, as we might like to believe.

Typical westerly wind flows across the mid-latitudes of the Northern Hemisphere mean air pollution from China is often carried over the Pacific Ocean. If the weather conditions are right, contaminants including mercury, ozone, sulphur and nitrogen oxides, black carbon and desert dust, can reach the west coast of the US within days.

The most visible recent examples were the giant dust storms originating from the Gobi desert in 1998 and 2001, which carried significant levels of pollutants across to the US. At the time, researchers feared this could be the start of an era of Chinese pollution dumping itself on the US. However, a similar large event has not occurred since, although smaller dust storms are still frequent.

Far more common, says Jaffe, have been the ozone events. These are not visible in the same way as giant dust storms, so haven´t garnered the same level of interest, but have proven to be damaging to public health and air quality standards. Levels of ozone detected at the mountaintop research centre have been "creeping up" over the past decade, according to data collected at the site, a result linked to, among factors, rapidly increasing vehicle emissions from Asia.

Whereas ozone high up in the atmosphere helps filter the sun's ultra-violet rays, ozone closer to ground level causes lung damage and is a particular risk to young children and asthma sufferers.

"We can point to quite a number of days of high ozone reaching our research station and contributing to days that violate air standards across the US," says Jaffe. "They're not as spectacular as dust storms and you don't see them on satellite, but they are enough to break air quality standards two or three times a year."

Part of the problem is that standards in the US are getting higher, with the US Environmental Protection Agency (EPA) looking at tightening the emission rules because of the health implications of ozone. In a paper on the issue, International transport of air pollution, the EPA suggests that downwind air pollution from Asia would wipe out the improvements expected from recent national emission control programmes.

The realisation that air pollution can be transported thousands of miles from its source has led to a re-think among air-quality officials in US cities.

Legislation in the US designed to enforce air quality – principally the Clean Air Act – does have an exceptional events rule that grants cities exemptions if they can show the source of the bad air quality day was out of their control.

"In the past, when a city has a bad air day, they would normally assume the weather must have been too hot, the air stagnant, too many cars, factories. But there are days when they get bad air events and the air is not stagnant and they want to find out why," says Jaffe.

"It's only really in the last few years that our research has got down to the city-level, where they are starting to look and understand global air pollution."

Mercury pollutants and fish

The other most significant pollutant is mercury. Asia burns a lot of coal, and Chinese coal in particular contains a high amount of mercury, making the country the largest source of chemical in the world. Although there are ongoing UN negotiations on reducing mercury emissions, expectations that China will be willing to invest in technology, or be given help in getting technology, to reduce atmospheric emissions of mercury are low.

"So when the global community says you need to spend millions cleaning up your mercury because high-end consumers in San Francisco can´t eat fish, China goes 'give me a break that´s not our biggest problem'. Maybe in 10-20 years when it has dealt with its other issues it may be ready to tackle this,” says Jaffe, who adds that particulate matter (PM) air pollution in most Chinese cities, for example, is a much bigger problem.

Ironically, the US could also be contributing to its own mercury pollution too if it pushes through plans to scale up the export of coal to China.

US coal is already being exported to China through Canada. Just south of the west coast port city of Vancouver, the Westshore Coal Terminal ships 22 million tonnes of coal a year, of which 59% goes to China. There are now plans to build dozens of new terminals in the states of Washington and Oregon, on the west coast of the US, and export 150 million tonnes of coal a year to Asia.

"It's a classic jobs versus environment," says Jaffe, who lives in Washington state, which is phasing out its only coal-burning power station. "It's a dumb idea. We ship coal to China, they burn it and we get the pollution back."

A distant clean future

Jaffe believes both the US and China have different responsibilities when it comes to tackling air pollution. The US responsibility is maintaining high standards and not exporting coal to Asia, while for China it is continuing with what he says has been significant progress confronting its air quality problem.

"They´re putting huge amounts of money into science and technology and particularly environmental and air monitoring. You can now go online and get daily air-quality figures. I believe the data is fine. We´ve measured it ourselves. But if you convert it into western standards the levels are really high. The main difference is in the wording. They're reporting the number correctly, but how they´re grading it is very different.

"In the long run, if they clean up their own environmental problems it will, by necessity, help their downstream neighbours. If they have such horrible air quality in their cities which they know is both a health and economic issue, are they're going to spend 50 billion dollars on environmental progress to help their own citizens, or worry about people in Korea or the US?"

评论 comments

5

评论 comments

中文

EN

嗨 Hi Guest user

退出 Logout /


发表评论 Post a comment

评论通过管理员审核后翻译成中文或英文 最大字符 1200

Comments are translated into either Chinese or English after being moderated. Maximum characters 1200

排序 Sort By:

谁弄脏了中国的空气?

竟替美国人说话了,怎不见你提工业革命时谁污染了谁,是谁主动把耗能大污染大的产业转移到了中国?中国人呼吸着pm2.5爆表的空气辛苦劳作只赚得到半分半厘,欧美人在青山绿水边一边享用着廉价的中国制造,一边骂骂咧咧的嫌中国脏。

来自新浪微博网友评论

Who polluted China's air?

You stand by the US side? Why didn't you mention who polluted the environment during Industrial Revolution? Who transfered those heavy-polluted industries to China? Chinese people are suffering from extreme PM2.5 pollution but only earn little money, meanwhile, Americans and European enjoy cheap 'made in China' products and fresh air. Now they complain that China is dirty?

A comment from Sina Weibo


那就多花点钱采购中国制造吧,让中国企业也有利润治污

那么美国通过国会法案好了,强制性提高美国公司在华采购的价格,附加污染治理费用,好保护美国人自己

Buy more products from China, then Chinese companies can make more profits to fight pollution

US Congress should pass an Act on compulsorily increase the products' price which are sourcing in China. To pay extra 'Pollution Control' fee in order to protect themselves.


没见到一个“山顶研究中心”的数据。。。。。。

又看了一遍,还是没见到

Haven't seen any data from the monitoring site

I read through the article again, but haven't seen any data.


这是一个媒体人写的客观报道吗?

总是在危机了自己的时候才开始着急。地球是一个整体,你之前做了什么?!你倾销垃圾,迁移污染企业,出口煤炭到别人的地方,你以为自己能摆脱这些污染么?
敢问这位作者,你通篇引用一个学者的研究,难道你自己没有基本的事实判断吗?这是一个媒体人应具有的素质吗?

Is this a objective article written by a media professional?

It has been always like that people start to get anxious when things actually happened in their back yard. The whole world is a unit. What did you do to it in the past? You dumped garbage, transfered polluted industries, exported cold to other countries. Do you think by doing those you can get rid of pollutants?
I want to ask the author that as you quoted this study conducted by a researcher, don't you have your own judgements based on facts? That's the qualifications a professional should have?


You Are Polluting Your Own Air

Chinese factories have turned China into an ecological nightmare. Guess that mad dash towards industrialization has consequences eh? Guess all that cheap energy from coal fired power plants isn't that cheap now is it? Chinese people are selling out Chinese people in order to enrich themselves while everyone gets to breath air that isn't fit for breathing. Just wait until your children start show signs of respiratory illnesses such as asthma. Just wait until your citizens start experiencing respiratory illnesses on an epidemic level. People in the United States are going to fight tooth and nail to prevent more coal from being shipped over to China so you can send air borne pollution our way. Better get used to it. Buy a respirator...you're going to need it.

你在污染自己的空气

中国工厂把中国变成了一个生态噩梦。是工业化横冲直撞式的发展的后果吧?从烧煤的能源厂得到的廉价能源如今也没有那么便宜了吧?中国为了使自己更加富裕正在背叛所有的中国人,每个人都得吸入不宜呼吸的空气。等着瞧吧,你的孩子会有呼吸疾病的前兆,比如哮喘。等着瞧吧,你的公民会开始像染上流行病一样患上呼吸疾病。美国人民将全力阻止更多的煤炭被运到中国,否则空气污染最终又会回到我们。最好习惯它。买一个口罩吧...你会用得上的。


合作伙伴 Partners

项目 Projects