BEIJING, Nov. 10 (Xinhua) -- Since 2016, the proportion of days with excellent or good air quality in southwest China's Xizang Autonomous Region has reached over 99 percent each year, said a white paper issued by the State Council Information Office on Friday.

The air quality in main towns and cities has, on the whole, remained excellent or good, and the concentrations of six pollutants in seven prefecture-level administrative units has reached the state Grade-II standards or above. The air quality in the Mount Qomolangma area continues to be rated as excellent or good, reaching the state Grade-I standards, according to the white paper titled "CPC Policies on the Governance of Xizang in the New Era: Approach and Achievements."

In 2022, Lhasa ranked first among the 168 key cities in China in terms of air quality, and Nyingchi and Qamdo both enjoyed excellent air quality all year round, said the white paper. ■