MOUNTAINEERING -- Professional climber Melissa Arnot, 32, on Monday became the first American woman to reach the summit of Mount Everest and survive the descent without supplemental oxygen, according to Outside Online.

The records show that American climber Francys Distefano-Arsentiev reached the summit without oxygen in 1998 but died during the descent.

Arnot's ascent of the 29,035-foot peak’s northeast ridge from Tibet marked her sixth time on the top of the world. Her previous five Everest climbs were made via the more popular South Col route in Nepal. Arnot's Everest summit attempts in 2014 and 2015 were disrupted by avalanches.

Although more than 400 climbers have reached the summit of the world's highest peak -- and at least four have died -- in this year's mad dash, accomplishing the feat without supplemental oxygen is a tremendous physical feat.

Outside writers Devon O'Neil & Grayson Schaffer put it in perspective:

Of the 7,001 Everest summits going into this season, according to the Himalayan Database, only 193—or 2.7 percent—did not involve supplemental oxygen. Above 26,000 feet, in what’s known as “the death zone” the human body can no longer acclimatize to the altitude. In order to function at that elevation, most people need to use tanks of supplemental oxygen in order to maintain circulation, stay warm, and maintain mental and motor skills.

“Plenty of people talk about doing it, but getting it done is actually quite rare and impressive,” wrote guide and 15-time Everest summiter Dave Hahn in an email to Outside. “It wasn’t accidental that she succeeded. Melissa made the commitment and put in a ton of flat-out hard work over the years to make this happen.”

More about Arnot from Wikipedia:

Arnot was raised just outside Glacier National Park in Whitefish, Montana. After college, she began living out of her car to save money and climb mountains. She first climbed Mount Rainier in 2001 and called it a "watershed moment". She began teaching wilderness medicine in 2002 and began guiding on Mount Rainier with Rainier Mountaineering, Inc. in 2004. By 2006 she was a lead guide.

Since 2001, she has summited Rainier more than 90 times. She also a certified Wilderness EMT and teaches Wilderness EMT courses.

In 2010, she led a celebrity climb up Mount Kilimanjaro to raise awareness for clean water access. The effort, Summit on the Summit, included actors Emile Hirsch, Jessica Biel and Isabel Lucas, musicians Kenna, Lupe Fiasco and Santigold, as well as various scientists and activists, and aired as an MTV special.

She is currently sponsored by Eddie Bauer and Whittaker Mountaineering, a retail store based in Ashford, Washington.

Arnot’s notable big mountain ascents include:

• 92 summits of Mount Rainier (14,410')
• 6th summit of Mount Everest in 2016
• 5 summits of Mount Everest (29,029') by 2012, (South Col route)
• 3 summits of Aconcagua, Argentina (22,841')
• 1 expedition on Mount McKinley (20,320')
• 5 summits of Cotopaxi, Ecuador (19,348')
• 2 expeditions on Cayambe, Ecuador (18,997')