American mountaineer, author and artist, best known for his book, The Challenge of Rainier, first published in 1971 and considered the definitive work on the climbing history of Mount Rainier, the highest mountain in the U.S. state of Washington.
Molenaar was born to Dutch immigrant parents. During World War II, he served as a photographer in the U.S. Coast Guard in the Aleutians and western Pacific. In 1950, he earned a BSc degree in geology at the University of Washington, and then served as civilian advisor in the Army’s Mountain & Cold Weather Training Command at Camp Hale, Colorado.
Molenaar worked as a park ranger and mountain guide in Mount Rainier National Park, climbing the mountain over 50 times as a guide and on personal trips, via more than a dozen different routes including three first ascents. He participated in the 1946 second ascent of Mount Saint Elias in Alaska. He was a member of the Third American Karakoram Expedition, a 1953 mountaineering expedition to K2 in which the party became trapped during a severe storm. Along with “Big Jim” Jim Whittaker and Robert Kennedy, he was a member of the 1965 climb and first ascent of Mount Kennedy in the Yukon, named after John F. Kennedy.
Molenaar painted in watercolours and oils. He is known for his impressionism-style art with mountain and desert landscapes the dominant theme in his works. He painted the highest watercolour in history, spending 10 days in a tent painting K2 from memory at 25,000 feet (7,600 metres) during a severe storm that hit during the 1953 expedition.
His career with the U.S. Geological Survey took him to Alaska, Colorado, Utah, and Washington, until his retirement in 1983. Dee Molenaar died on 19 January 2020 at age 101.

Link to Wikipedia biography