冒頭の衛星写真は、2013年12月7日に撮影されたものだ。北京から上海まで、1200キロメートル以上にわたってスモッグが広がっている様子がわかる。撮影したNASAの説明によると、白いのは雲や霧であり、スモッグは灰色の渦状として写っているという。
上海当局は12月はじめ、大気汚染が危険レベルに達したことを受け、学校の休校および建築作業一時中止の措置を取った。12月13日には、微小粒子状物質（PM2.5）の濃度が一立方メートル当たり602.5マイクログラムに達した、とAPが伝えている。世界保健機構（WHO）が設定した指針は24時間平均が25マイクログラムだ（Wikipediaによると、米国や日本の基準は35マイクログラム。）。
大気汚染は、人々の健康だけでなく、視界にも影響を与えている。APによれば、北京空港を定刻通りに離陸する便は現在、わずか18％であり、この数字は世界で最悪だという。
中国民用航空局は来年1月1日より、中国各地から北京に向かう国内路線の機長に対し、視界不良時に計器を使った自動着陸を行わせる方針だと報道されている。現在は、視界が400メートル以下の場合は別の空港に誘導されているが、来年からは自動着陸装置を利用することになるという。
[James Gerken(English) 日本語版：ガリレオ]
ハフィントンポスト日本版はFacebook ページでも情報発信しています。
関連記事
中国 大気汚染 画像集
(01 of17)
A little tourist wearing the PM2.5 mask walk on the Tiananmen Square during severe pollution on January 31, 2013 in Beijing, China. (Photo by Feng Li/Getty Images) (credit:Getty Images)
(02 of17)
Traffic moves along a street as pedestrians walk on an overpass shrouded in haze in Beijing, China, on Friday, March 15, 2013. China\'s new premier promised to crack down on corruption and clean up pollution, acknowledging the need to tackle two issues that have stoked public anger toward the country\'s leaders. (credit:Tomohiro Ohsumi / Bloomberg / Getty Images)
(03 of17)
Traffic moves along a street as pedestrians walk on an overpass shrouded in haze in Beijing, China, on Friday, March 15, 2013. China\'s new premier promised to crack down on corruption and clean up pollution, acknowledging the need to tackle two issues that have stoked public anger toward the country\'s leaders. (credit:Tomohiro Ohsumi / Bloomberg / Getty Images)
(04 of17)
Haze surrounds the International Commerce Centre (ICC) in the West Kowloon district of Hong Kong, China, on Monday, April 15, 2013. Hong Kong\'s air pollution index reached the \"severe\" level for the third time this year, triggering a government warning, as the lack of air flow trapped pollutants in the city. (credit:Jerome Favre / Bloomberg / Getty Images)
(05 of17)
Diesel fumes come out of a tug boat chimney as skyscrapers stand in the Wanchai district of Hong Kong, China, on Monday, April 15, 2013. Hong Kong\'s air pollution index reached the \"severe\" level for the third time this year, triggering a government warning, as the lack of air flow trapped pollutants in the city. (credit:Jerome Favre / Bloomberg / Getty Images)
(06 of17)
A man wears a mask as he walks down a street in Beijing, China, on Friday, March 15, 2013. China\'s new premier promised to crack down on corruption and clean up pollution, acknowledging the need to tackle two issues that have stoked public anger toward the country\'s leaders. (credit:Tomohiro Ohsumi / Bloomberg / Getty Images)
(07 of17)
Traffic moves along a street shrouded in haze in Beijing, China, on Friday, March 15, 2013. China\'s new premier promised to crack down on corruption and clean up pollution, acknowledging the need to tackle two issues that have stoked public anger toward the country\'s leaders. (credit:Tomohiro Ohsumi / Bloomberg / Getty Images)
(08 of17)
A woman wears a mask as she walks on a street in Beijing, China, on Friday, March 15, 2013. China\'s new premier promised to crack down on corruption and clean up pollution, acknowledging the need to tackle two issues that have stoked public anger toward the country\'s leaders. (credit:Tomohiro Ohsumi / Bloomberg / Getty Images)
(09 of17)
This picture taken on January 29, 2013 shows a general view of buildings in the heavy smog in Jilin, northeast China\'s Jilin province. Beijing urged residents to stay indoors on January 30 as emergency measures were rolled out aimed at countering a heavy cloud of smog blanketing the Chinese capital and swathes of the country. (STR/AFP/Getty Images) (credit:Getty Images)
(10 of17)
Chinese tourists look at the view from the historic Jingshan Park as smog continues to shroud Beijing on January 31, 2013. (MARK RALSTON/AFP/Getty Images) (credit:Getty Images)
(11 of17)
Two Chinese policemen guard in front of two LED screens on the Tiananmen Square during severe pollution on January 31, 2013 in Beijing, China. (Photo by Feng Li/Getty Images) (credit:Getty Images)
(12 of17)
A general view shows the Guotai Chambers building from the historic Jingshan Park as smog continues to shroud Beijing on January 31, 2013. (MARK RALSTON/AFP/Getty Images) (credit:Getty Images)
(13 of17)
A Chinese tourist takes photos from the historic Jingshan Park as smog continues to shroud Beijing on January 31, 2013. (MARK RALSTON/AFP/Getty Images) (credit:Getty Images)
(14 of17)
Chinese tourists looks at the view from the historic Jingshan Park as smog continues to shroud Beijing on January 31, 2013. (MARK RALSTON/AFP/Getty Images) (credit:Getty Images)
(15 of17)
Tourists visit the Tiananmen Square during severe pollution on January 31, 2013 in Beijing, China. (Photo by Feng Li/Getty Images) (credit:Getty Images)
(16 of17)
A little tourist wearing a panda mask walk on the Tiananmen Square during severe pollution on January 31, 2013 in Beijing, China. (Photo by Feng Li/Getty Images) (credit:Getty Images)
(17 of17)
The little tourists play on the ground with frozen ice at the Tiananmen Square during severe pollution on January 31, 2013 in Beijing, China. (Photo by Feng Li/Getty Images) (credit:Getty Images)