As the new year begins, Beijing has already delivered its 2024 "Blue Sky Defense" results. The annual PM2.5 concentration stood at 30.5 μg/m3, a 6.2% drop from last year. For the fourth year in a row, Beijing has met the national air quality Grade II standard, with 290 days of good and moderate air quality — the highest on record. How did Beijing achieve this? How did other cities perform? Find out in #BlueMap Air Quality Dynamics.