A dispute over the height of North America’s tallest mountain may be resolved this week, as surveyors climb to the top of Mount McKinley.
McKinley, recognized throughout Alaska by its Koyukon Athabascan name: Denali, has long been thought to stand at 20,320 feet, a measurement recorded in 1953. That number was contested in 2013, when the United States Geological Survey (USGS) used radar technology to re-calculate the mountain’s height. The result was a mere 20,237 feet — 83 feet lower than the previously recognized elevation.
“People didn’t like the lower number,” said David Moune, Senior Project Manager with Dewberry Geospacial Products and Services – a company contracted by USGS to perform the 2013 survey. “And I was bothered by it myself. I mean I had people say, ‘It’s still over 20,000 feet, I hope?’ And I said, ‘Yes it’s still over 20,000 feet, but I don’t know how much over 20,000 feet.'”
Moune said the new elevation, in addition to being controversial, may not be entirely accurate. He explained the measurement was taken from the air using radar frequencies, to create 3D images as part of an ongoing mapping project around the state. While that technique is great for mapping complex terrain in 3D, Moune said its single-point elevation measurements could be off by several meters.
According to Moune, the most accurate way to measure height for a specific peak is to use GPS. But for that, you need old-fashioned boots on the ground.
“We’re up at 14,000 feet on Denali on the summit survey expedition,” Blain Horden reported by satellite phone Monday.
Horden is leading those boots — and a team of three surveyors — to the summit of Denali this week, as part of an expedition sponsored by USGS, NOAA’s National Geodetic Survey, and University of Alaska Fairbanks. Their mission: To set the record straight.
As of Monday night, Horden’s team had settled in at 14,000 feet, with plans to push for the summit as early as Wednesday. But Moune says the task of measuring a mountain isn’t an easy one.
“These guys are not just taking themselves to the top of the mountain. They are carrying a lot of equipment with them. That all adds to the complexity of the climb,” he said.
In addition to challenges faced by all high-altitude climbers, the surveyors will need to clear a few logistical hurdles. For example: finding the physical peak of Denali — rock that has long been buried under ice and snow.
This is an ambitious goal. No survey of the mountain has yet calculated elevation using its natural peak; all measurements have been taken from ice resting on top of Denali. Which could have contributed to some level of error in the past, according to Moune.
“People want to know how high is Denali. And perhaps the best we can do is tell them how high the ice and snow is in 2015 on the day that we surveyed it. Recognizing that the thickness of the ice and snow may change whenever it snows and rains up there. Or melts for that matter,” he said.
But even if Horden’s team also measures from the ice at Denali’s summit, Moune added, the data they gather will still provide an improved estimate of the mountain’s true height. The expedition could take as long as three weeks to complete, but surveyors are currently ahead of schedule — and could begin their descent by the end of this week.
And the height of the continent’s tallest mountain isn’t the only thing up for debate. The name of the famous Alaskan peak has long been a point of contention — both in, and out, of state.
Alaskans have filed several federal bills since 1975 to change the name from Mount McKinley — after former president William McKinley — to Denali, a traditional Koyukon Athabascan term meaning “high one” or “great one.”
That effort has been largely opposed by representatives from McKinley’s home state of Ohio, with Rep. Bob Gibbs filing a bill that would stop the U.S. Board of Geographic Names from changing the mountain’s title as recently as March.
Last month, Sen. Lisa Murkowski introduced yet another bill to name the mountain Denali in honor of the region’s Native heritage. It remains unclear whether either legislator will succeed in pushing their bill through the Senate or the House.