Aerial photo taken on Dec. 8, 2019 shows the scenery along the Yarlung Zangbo River in southwest China's Tibet Autonomous Region. (Xinhua/Purbu Zhaxi)

Aerial photo taken on Dec. 8, 2019 shows the scenery along the Yarlung Zangbo River in southwest China's Tibet Autonomous Region. (Xinhua/Purbu Zhaxi)

Aerial photo taken on Dec. 8, 2019 shows the scenery along the Yarlung Zangbo River in southwest China's Tibet Autonomous Region. (Xinhua/Purbu Zhaxi)

Aerial photo taken on Dec. 8, 2019 shows the scenery along the Yarlung Zangbo River in southwest China's Tibet Autonomous Region. (Xinhua/Purbu Zhaxi)

Aerial photo taken on Dec. 8, 2019 shows the scenery along the Yarlung Zangbo River in southwest China's Tibet Autonomous Region. (Xinhua/Purbu Zhaxi)

Aerial photo taken on Dec. 8, 2019 shows the scenery along the Yarlung Zangbo River in southwest China's Tibet Autonomous Region. (Xinhua/Purbu Zhaxi)

Aerial photo taken on Dec. 8, 2019 shows the scenery along the Yarlung Zangbo River in southwest China's Tibet Autonomous Region. (Xinhua/Purbu Zhaxi)

Aerial photo taken on Dec. 8, 2019 shows the scenery along the Yarlung Zangbo River in southwest China's Tibet Autonomous Region. (Xinhua/Purbu Zhaxi)

Aerial photo taken on Dec. 8, 2019 shows the scenery along the Yarlung Zangbo River in southwest China's Tibet Autonomous Region. (Xinhua/Purbu Zhaxi)

Aerial photo taken on Dec. 8, 2019 shows the scenery along the Yarlung Zangbo River in southwest China's Tibet Autonomous Region. (Xinhua/Purbu Zhaxi)

Aerial photo taken on Dec. 8, 2019 shows the scenery along the Yarlung Zangbo River in southwest China's Tibet Autonomous Region. (Xinhua/Purbu Zhaxi)