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Taking the measure of a mountain

 

14,410 feet, or 14,411? What's Mount Rainier's official summit elevation? The U.S. Geological Survey says there isn't one.

 

CRAIG HILL; The News Tribune

Published: November 16th, 2006 01:00 AM

 

 

Eight hours after we stood on the roof of Washington last summer, our guides rewarded us with certificates that read “Mount Rainier, 14,410 feet.”

 

Aware many others believe the mountain is actually a foot taller, I raised my hand to get the scoop from Alex Van Steen, our lead guide from Rainier Mountaineering Inc.

 

“Hey, what happened to the extra foot?” I asked. “I’m pretty sure I felt it up there.”

 

“Nope,” Van Steen said with a smile. “The official height is 14,410 and 13 inches.”

 

Van Steen isn’t the only person who has his bases covered.

 

Ashford resident Steve Miller has vanity plates with Rainier’s elevation for his cars. The plates read “14410” on his Toyota pickup and “14411” on his Subaru Forester.

 

So what’s in a foot?

 

Most people – including career climbers and the U.S. Geological Survey – don’t really seem to care.

 

In fact, it doesn’t have official summit elevations for most mountains, including Rainier, said Steve Reiter of the USGS. The 14,410 USGS listing on maps is calculated from the agency’s highest Rainier benchmark, which is at 14,399 feet. A benchmark is a permanent point whose known elevation is part of a national network.

 

Mount Rainier National Park climbing ranger Mike Gauthier recently made the mistake of saying he didn’t care about the differing elevations during a slide-show presentation.

 

“Sure enough, some guy raised his hand,” Gauthier said. “It’s a big issue to some people. … It’s the state’s icon. It’s on the license plate.”

 

That’s precisely why people like Paul White think there should be an agreed-upon official elevation.

 

“If it was some other mountain, it wouldn’t be that important,” said White, a Lakewood resident. “But it’s our symbol. It’s going to be on the Washington quarter. They wouldn’t have remeasured it if it wasn’t important.”

 

In fact, it was the remeasurements in 1989 and 1999 for the state and national park’s respective centennials that tacked on the extra foot to the USGS 1956 measurement.

 

Using Global Positioning Satellites, the Land Surveyors Association of Washington calculated Rainier’s elevation at 14,411.1 in ’89 and 14,411.05 in ’99.

 

After the measurements, many changed their references for Rainier, but others stuck with the USGS calculation.

 

The result has been a sometimes humorous, often overlooked discrepancy that has become a curious Rainier footnote.

 

When two climbing guidebooks to Rainier were published in 1999, the first, written by Van Steen and Fred Beckey, listed the summit at 14,411 feet. A few months later, Gauthier’s version said 14,410.

 

Eric Simonson says his company, International Mountain Guides, uses 14,411 feet, even though his Web site says 14,410.

 

“I guess it depends on the day of the week and who you are talking to,” Simonson said.

 

Even the USGS has one reference to the higher elevation on its Web site, and Reiter says the GPS measurement is likely more accurate.

 

Wikipdia.com lists both elevations in the same article.

 

And, for good measure, the Smithsonian lists the elevation at 14,409 feet.

 

“Which elevation is most accurate?” said Dave Doyle of the National Geodetic Survey. “Well, that’s the stuff graduate degrees are made off.”

 

NOT OFFICIAL

 

Reiter says it’s a common misconception that there is a USGS benchmark at the summit of every mountain. In fact, the exact summit elevation isn’t vital to the USGS, he says.

 

The highest benchmark on Rainier is 14,399 feet, placed in the highest exposed rock outcropping.

 

“We place the benchmarks at known locations and elevations that are ideal for surveyors,” Reiter said, adding that precise summit elevations often aren’t necessary for making accurate maps.

 

From these benchmarks, the USGS calculates summit elevations.

 

Doyle says the USGS’ calculation of Rainier’s summit has a margin of error of plus or minus 5 feet.

 

“Most people are surprised to learn that quite a few famous peaks like Rainier don’t have official elevations,” Reiter said.

 

The USGS hasn’t measured any mountains in Washington since the arrival of GPS technology in the late 1970s, although they do use GPS.

 

Mount Rainier National Park uses 14,410 feet for the elevation because it uses USGS numbers, said park natural resources manager Roger Andrascik.

 

THE 1956 MEASUREMENT

 

Before Enumclaw’s Larry Signani led the GPS measurements of Rainier, he got hold of the notes from the USGS’ 1956 measurement.

 

According to the notes, the summit’s elevation was set based on the average of several triangulation measurements. And because of the margin of error, Signani says the elevation was rounded up as much as 2 feet, to 14,410.

 

“This is not saying anything negative about past measurements,” Signani said. “This is the best they had at the time.”

 

GPS: 14,411.05

 

Rainier was the first mountain measured using GPS technology in 1989. The Land Surveyors of Washington, led by Signani, hauled two suitcase-size GPS receivers to the summit.

 

For reference, 12 more receivers were placed at known elevations on and around Rainier.

 

“The more reference sites you use, the more accurate the reading,” Signani said.

 

In 1999, the surveyors used 16 reference receivers in measuring an elevation 1.5 centimeters shorter than their first measurement.

 

“Our measurements are accurate within a centimeter,” Signani said. “That’s pretty accurate.”

 

RIGHT ROUND, FOR THE RECORD

 

The Smithsonian Institution lists the summit of Rainier at 14,409 feet.

 

Lee Siebert, the Smithsonian’s volcano data specialist, says the difference is likely a rounding issue.

 

The Smithsonian uses USGS measurements; however, many USGS maps list Rainier at 4,392 meters. Sure enough, the conversion gives you an elevation of 14,409.4 feet. However, the USGS had already rounded down from about 4,392.2 meters – a difference of about 8 inches.

 

The North Dakota Space Grant Consortium uses Smithsonian data. However, after being contacted by The News Tribune, the consortium’s content editor – Oregon State University geosciences graduate student Chris Harpel – said the organization plans to switch to 14,410 feet to match the USGS.

 

Siebert did not indicate if the Smithsonian will change its elevation.

 

WHERE’S ZERO?

 

You aren’t going to get college credit for reading this section, but you probably should.

 

We’ll start with a quiz.

 

Mount Rainier is 14,411 (or 14,410) feet above what?

 

A. Mean sea level.

 

B. The geoid.

 

C. The reference ellipsoid.

 

If you said A or B you are correct. If you said C, you are off by 63.1 feet.

 

The USGS has always used height above sea level for its elevations, and as a result that has become the popular reference.

 

However, because the ocean’s surface rises and falls depending upon gravitational pull, sea level differs by location, Reiter said. And because most mountains don’t rise directly from the sea, scientists created a reference called the geoid, which extends mean sea level over the continents.

 

GPS technology measures height above another imagined Earth surface – the reference ellipsoid.

 

This is a smooth egg-shaped reference roughly Earth’s size and figure. In some places, the ellipsoid is below mean sea level, and in others, like the United States, it is above. GPS elevation is usually converted to feet above sea level.

 

At Mount Rainier, the ellipsoid is 63.1 feet above mean sea level, according to USGS records, so you would add that figure to the GPS measurement.

 

“Basically determining the elevation comes down to ‘Where is zero?’” Reiter said. “And can you even determine where zero is.”

 

Not confusing enough? For extra credit, check out the National Geodetic Survey’s explanation at www.ngs.noaa.gov/GEOID.

 

UPS AND DOWNS

 

The elevation of Mount Rainier’s summit changes all the time.

 

Because there is no exposed rock at Rainier’s highest point, the summit rises and falls depending on the temperature, snowfall and summit traffic.

 

“Depending on if it’s summer or winter, it fluctuates a few feet,” said Peter Whittaker, RMI’s CEO. “What I know for sure is it’s a darn long way up there.”

 

For those who make a living on the mountain, the summit seemed especially low this summer.

 

“I think it was about a foot lower than normal this year because it was so warm,” said Gauthier, Mount Rainier National Park’s lead climbing ranger. “I even saw a small crevasse near the summit for the first time.”

 

HOME MEASUREMENTS

 

So, maybe you’re thinking, “I have a GPS handset; why don’t I just hike up there and put an end to the debate?”

 

Well, it’s not that simple.

 

Standing on the summit last year, I got a reading that wasn’t even close. After adding my geoid height (the difference between mean sea level and the ellipsoid), my handset said 14,151 feet above sea level.

 

“That doesn’t surprise me,” Signani said. “Those little handheld receivers only have an accuracy within about 30 meters (981/2 feet) when you are measuring elevation. Plus, it has no reference points like we do when we use survey quality GPS, so that’s going to make it even less accurate.”

 

How about an altimeter?

 

“Altimeters are unreliable, too, because they are based on barometric pressure,” Signani said. “They are effected by temperature and humidity, so your reading will be different day to day.”

 

THE FUTURE

 

Soon surveyors in Washington will be able to measure Rainier – and everything else in the state – even more accurately.

 

The state is installing a web of continuously running GPS stations called the Washington State Reference Network.

 

“This will revolutionize the way we determine elevations,” Signani said. “It allows for centimeter positioning. This is the measurement future for Washington.”

 

TNT STYLE

 

It wouldn’t be fair to point out the inconsistencies of others without taking a shot at ourselves.

 

The News Tribune has bounced between both elevations since the 1999 GPS measurement. We used 14,411 feet in stories last summer, but we’ve used the shorter height in stories as recently as last month. We don’t have an official elevation in our local stylebook.

 

Hardly the consistency you’d expect from an organization that not only prides itself on accuracy but also has the mountain in its logo.

 

However, after researching this story, we’ve decided to settle on 14,411 feet as our official style.

 

“The first rule of journalism is accuracy. It’s also the second rule. And the third,” said News Tribune editing team leader Jim Kresse. “It just makes sense to go with the survey that uses the latest technologies and most recent measurements that give the most accurate reading.”

 

Craig Hill: 253-597-8497

 

craig.hill@thenewstribune.com

 

THE EVER-CHANGING ELEVATION

 

Year, Elevation, Credit, Method

 

1841 12,333 Lt. Charles Wilkes Triangulation

 

1879 14,444 James Smyth Lawson Barometer

 

1888 14,524 E.S. Ingraham Barometer

 

1896 14,519 USGS Barometer

 

1897 14,528 Edgar McClure Barometer

 

1902 14,363 USGS Barometer

 

1905 14,394 Alexander McAdie Barometer

 

1914 14,408 USGS Triangulation

 

1956 14,410 USGS Triangulation

 

1989 14,411.1 LSAW GPS

 

1999 14,411.05 LSAW GPS

SOURCES: National Park Service and Land Surveyors of Washington

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