It seems Beijing will reach its Clear Sky Days target of 245 days for 2007; with 33 days to go, we already have had 229 days with API less or equal to 100, so we only need 16 more (leaving out the mystery day of 20 August). Applause for all the officials who worked hard to accomplish this. But wait, there is more to this, read on.
If we change the interpretation of Clear Sky Day to an API less than 100 (not counting the days with exactly 100) then we have only 220 days and still need 25 out of 33 which is most probably not going to happen, so the difference between making the target and not making it is in fact very small.. But SEPA does include an API of 100 in its grade 2 ‘good’ so it counts as a Clear Sky Day.
Making a histogram of the API values of 2007 (counting the occurences of values), we see that the most occuring values are:
- 98 (21 days)
- 99 (11 days)
- 100 and 95 (both 9 days)
Isn’t that wonderfully helpful that the values tend to stay just on the good side of 100? The value of 101 has not even occurred ONCE, and see the amazing drop after 100.. The guy in charge of publishing these API data deserves a promotion, the government’s target will be met!