Aerial photo taken on Dec. 16, 2020 shows a view over the Yarlung Zangbo River in Zhanang County, Shannan City of southwest China's Tibet Autonomous Region. (Xinhua/Zhan Yan)

Aerial photo taken on Dec. 16, 2020 shows a view over the Yarlung Zangbo River in Zhanang County, Shannan City of southwest China's Tibet Autonomous Region. (Xinhua/Wang Zehao)

Aerial photo taken on Dec. 16, 2020 shows a view over the Yarlung Zangbo River in Zhanang County, Shannan City of southwest China's Tibet Autonomous Region. (Xinhua/Wang Zehao)

Aerial photo taken on Dec. 16, 2020 shows a view over the Yarlung Zangbo River in Zhanang County, Shannan City of southwest China's Tibet Autonomous Region. (Xinhua/Wang Zehao)

Aerial photo taken on Dec. 16, 2020 shows a view over the Yarlung Zangbo River in Zhanang County, Shannan City of southwest China's Tibet Autonomous Region. (Xinhua/Wang Zehao)

Aerial photo taken on Dec. 16, 2020 shows a view over the Yarlung Zangbo River in Zhanang County, Shannan City of southwest China's Tibet Autonomous Region. (Xinhua/Zhan Yan)

Aerial photo taken on Dec. 16, 2020 shows a view over the Yarlung Zangbo River in Zhanang County, Shannan City of southwest China's Tibet Autonomous Region. (Xinhua/Wang Zehao)

Aerial photo taken on Dec. 16, 2020 shows a view over the Yarlung Zangbo River in Zhanang County, Shannan City of southwest China's Tibet Autonomous Region. (Xinhua/Zhan Yan)

Aerial photo taken on Dec. 16, 2020 shows a view over the Yarlung Zangbo River in Zhanang County, Shannan City of southwest China's Tibet Autonomous Region. (Xinhua/Wang Zehao)

Aerial photo taken on Dec. 16, 2020 shows a view over the Yarlung Zangbo River in Zhanang County, Shannan City of southwest China's Tibet Autonomous Region. (Xinhua/Zhan Yan)

Aerial photo taken on Dec. 16, 2020 shows a view over the Yarlung Zangbo River in Zhanang County, Shannan City of southwest China's Tibet Autonomous Region. (Xinhua/Zhan Yan)

Aerial photo taken on Dec. 16, 2020 shows a view over the Yarlung Zangbo River in Zhanang County, Shannan City of southwest China's Tibet Autonomous Region. (Xinhua/Wang Zehao)

Aerial photo taken on Dec. 16, 2020 shows a view over the Yarlung Zangbo River in Zhanang County, Shannan City of southwest China's Tibet Autonomous Region. (Xinhua/Zhan Yan)

Aerial photo taken on Dec. 16, 2020 shows a view over the Yarlung Zangbo River in Zhanang County, Shannan City of southwest China's Tibet Autonomous Region. (Xinhua/Zhan Yan)

Aerial photo taken on Dec. 16, 2020 shows a view over the Yarlung Zangbo River in Zhanang County, Shannan City of southwest China's Tibet Autonomous Region. (Xinhua/Wang Zehao)