Half Dome above Yosemite's Glacial Valley

Half Dome above Yosemite's Glacial Valley is an original illustration set in Half Dome, Yosemite National Park, USA. It lies in mid-latitudes, where the climate is warm-summer mediterranean.

Half Dome rises at the head of Yosemite Valley with a smooth rounded shoulder and an abrupt vertical face. Pine forest and a bright bend of the Merced River occupy the flat valley floor, pale granite walls frame both sides, and a thin seasonal waterfall descends from a hanging valley in clear afternoon light.

Why does this granite dome have one rounded side and one sheer face?

Granite crystallized deep underground and was exposed as overlying rock eroded away. Curving exfoliation joints peeled slabs from the summit to round the dome, while a major vertical fracture created a plane that glaciers and repeated rockfalls could steepen into the famous face. The broad flat floor and hanging waterfalls record the same glacial excavation, so Half Dome's asymmetry is not a single break but the combined result of jointing, ice and continuing erosion.

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