Friday, May 08, 2009

Beijing Announces Cleanest Month in 9 Years?

May 14th, 2009. Note:
Thanks to Vance for flagging the editorial mistake by China Daily. This is the "cleanest April" in 9 years.


Blue Skies are Shining on Beijingers ! says China Daily

The city experienced 23 blue sky days in April, 2009 (a blue sky day = day with API less than 100).

Question: Why is this the cleanest month in 9 years,
August 2008, 30 days with average API of 56;
September, 2008, 29 days with average API of 56;
August 2006, 30 days with average API of 74;

and April 2009, 23 days with average API of 84?

See statistical Beijing Air Pollution Index (API) analysis @ Room with a View

Also see


Vance said...

Hi Sarath,

FYI, the China Daily misrepresented the official announcement, which stated that April 2009 was the cleanest April since 2000, not the cleanest month overall. More details here:


Sarath Guttikunda said...

Dear Vance,

thank you for clarifying the editorial mistake.