Weather conditions in Beijing in 2009

In 2009, the number of days with excellent air quality in Beijing was 285 days, accounting for 78. 1%, which was more than that in 2008 1 1 day and 25 days more than the annual air quality improvement target of 260 days, and the air quality 1 1 year was continuously improved. The annual air quality improvement target was completed 4 1 day ahead of schedule, which is the earliest year since 1999. The number of days of reaching the standard increased significantly, and the number of days of moderate and severe pollution above Grade 4 decreased significantly. The number of days with Grade II or better is 285 days, which is 16.8 percentage points higher than that in the same period since 2000, and the number of days with Grade IV or above is 5 days, which is the least number of days with moderate and severe pollution in the same period in recent ten years and lower than that in the same period in 2000 18 days.