Professional mountain guide Tsering walks past the East Rongbuk glacier on Mount Qomolangma, on May 22, 2020. (Xinhua/Jigme Dorje)

Aerial photo taken on May 22, 2020 shows a view of the East Rongbuk glacier on Mount Qomolangma. (Xinhua/Jigme Dorje)

Professional mountain guide Tsering walks past the East Rongbuk glacier on Mount Qomolangma, on May 20, 2020. (Xinhua/Jigme Dorje)

Aerial photo taken on May 22, 2020 shows a view of the East Rongbuk glacier on Mount Qomolangma. (Xinhua/Jigme Dorje)

Aerial photo taken on May 22, 2020 shows a view of the East Rongbuk glacier on Mount Qomolangma. (Xinhua/Jigme Dorje)

Professional mountain guide Tsering walks past the East Rongbuk glacier on Mount Qomolangma, on May 22, 2020. (Xinhua/Jigme Dorje)