Beijing Air quality
2 min readBeijing Air quality
Joint research between American and Chinese researchers in 2006
concluded that much of the city’s pollution comes from surrounding cities and provinces.An average 35-60%of the pollution can be traced to sources outside the city.Shandong Province and Tianjin 三Municipality have a“significant influence on Beijing’s air quality””，partly due in the prevailing south/southeasterly flow during the summer and the mountains in the north and northwest.
In preparation for the 2008 Summer Olympics and to fulfill promises to clean up the city’s air，nearly USD 1.7 billion was spent.
Beijing also implemented a number of air improvement schemes during the Games，including stopping work on all construction sites，closing many factories in and around Beijing，closing some gas stations，and cutting motor traffic by half by limiting cars to odd or even days（based on license plate numbers）.Two new subway lines were opened and thousands of old taxis and buses were replaced to encourage residents to use public transport.The Beijing government encouraged a discussion to keep the odd-even scheme in place after the Olympics.Although the scheme was eventually lifted on September
212008it was replaced by new restrictions on government vehicles.
In addition，staggered office hours and retail opening hours have been encouraged to avoid the rush hour，and parking fees were increased.
Beijing is the first city in China to adopt the Chinese emission standard equivalent to the Euro 4.Some 357，000“yellow label”vehicles（whose emission levels are too high）have been banned from Beijing.
The government regularly uses cloud-seeding measures to increase the likelihood of rain showers to clear the air as well as to combat drought conditions in the area.
According to the United Nations Environment Programme
（UNEP），China has spent $17 billion over the last three years on a large-scale environmental protection.Beijing has added 3，800 natural gas buses，one of the largest fleets in the world.Twenty percent of the Olympic venues’electricity comes from renewable energy sources.
The city has also planted hundreds of thousands of trees and increased green space in an effort to make the city more livable.
One year after the 2008 Olympics，Beijing’s officials reported that the city was enjoying the best air quality this decade because of the measures taken during the Games.Nonetheless，Beijing still faces air pollution problems.The US embassy recorded levels of pollution beyond measurable levels on February 21，2011 and advised people to stay indoors as a thick smog was covering the city.In January 2013
the monitor showed Air Quality Index（AQI）as measured by the density of particulate matter smaller than 2.5 micrometres in size-
higher than the maximum 500ug/m3 the US Embassy’s equipment can measure.
Daily pollution readings at 27 monitoring stations around the city are reported on the website of the Beijing Environmental Protection Bureau（BJEPB）.The United States Embassy in Beijing also reports hourly fine particulate（PM2.5）levels on Twitter.
