Aerial view of ice-covered Ra'og Lake in Qamdo, Tibet

Aerial photo taken on Feb. 16, 2021 shows ice-covered Ra'og Lake in Qamdo, southwest China's Tibet Autonomous Region. (Xinhua/Sun Fei)

Aerial photo taken on Feb. 16, 2021 shows ice-covered Ra'og Lake in Qamdo, southwest China's Tibet Autonomous Region. (Xinhua/Sun Fei)

Aerial photo taken on Feb. 16, 2021 shows ice-covered Ra'og Lake in Qamdo, southwest China's Tibet Autonomous Region. (Xinhua/Sun Fei)

Aerial photo taken on Feb. 16, 2021 shows ice-covered Ra'og Lake in Qamdo, southwest China's Tibet Autonomous Region. (Xinhua/Sun Fei)

Aerial photo taken on Feb. 16, 2021 shows ice-covered Ra'og Lake in Qamdo, southwest China's Tibet Autonomous Region. (Xinhua/Sun Fei)