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Home arrow Archives   The American Surveyor     

Just Say You've Been There Print E-mail
Written by Eric Stahlke, LS, CFedS   
Thursday, 21 October 2010

A 1.273Mb PDF of this article as it appeared in the magazine—complete with images—is available by clicking HERE

Fellow surveyors, who among us has not, at some point in our careers, lost a little sleep thinking about an error in our work that others may not even notice? After all, the public trusts our judgment in matter of boundaries and we have certain responsibilities.

I can remember early in my career when that particular responsibility had not fully established itself in my value system. At that time I was working with the BLM as a second year trainee on a cadastral survey crew and we happened to be based in a small town in the four corners area, so named for that single point which is common to the corners of the states of Utah, Colorado, New Mexico and Arizona. Today this point is easily accessible by paved road and is probably the most visited survey monument in the United States, with thousands of tourists making the journey annually. But in 1971, before the area had been developed into a major tourist attraction, the monument was not easy to visit, located as it was at the end of a rutted unimproved road where you were likely as not to get lost or stuck in the drifting sand. But even then the people came. There is just something about straddling the boundaries of four states simultaneously that is irresistible.

Supplying directions to this monument was a responsibility that the local gas station apparently did not want on its conscience, especially when this task could be shifted to the BLM survey crew staying in town. After all, what good is a survey crew if they can't provide directions? So inevitably there would be somebody knocking on our motel room door inquiring which way to the "monument". Seeing a bunch of little kids and Grandma looking hopefully at us from the inside of a low slung station wagon, the last thing we wanted was to send them on a snipe hunt to the middle of nowhere where they were likely to get stuck or die of thirst. So we would try and talk them out of it.

"Why do you want to go to that godforsaken place? It's in the middle of nowhere," we would implore, to inevitably be rebuffed with the answer, "To say we've been there!" Who can argue with this logic?

Fortunately, not too far out of town was a shiny new township corner our crew had recently monumented, and next to this was a large rock cairn that had been constructed 75 years earlier during the original survey. It looked authoritatively official, and it was easy to drive to. So we gave directions to this spot to all but the most savvy. A cynical thing to do, I admit, but nobody was going to get stuck or die of thirst, and, most important, all could faithfully say with a clear conscience that they've "been there". If you can't trust a surveyor for this kind of information, who can you trust?

Instead it was my own conscience that took a beating. Years later, having acquired greater respect for boundaries, I regretted our actions at Four Corners. People had placed their faith in surveyors to help them out and we sold them snake oil instead.

I was reminded of this exactly 30 years later while surveying in the small Athabascan village of Allakaket, located on the Koyukuk River in north central Alaska. Allakaket is unique because the Arctic Circle passes through the village (at least it does according to most globes and state maps). The locals, on the other hand, were blissfully unaware of this fact. The moment of truth came one rainy afternoon while our crew was digging around town for some old lot corners when the village chief appeared in his pickup truck. He was accompanied by a well-dressed German tourist who had apparently arrived on the morning mail plane. The German seemed like a nice enough guy, but he couldn't speak any English other than to articulate the words "Arctic Circle". Apparently the poor man had flown all the way to Allakaket to see the Arctic Circle and nobody could help. In a flash of inspiration the chief brought him directly to us—thank God there were surveyors in town that could save the day!

Of course, we didn't have a clue either, but I wasn't going to ruin this guy's vacation. I drove him about a mile to where there was a nice clean brush line marking the boundary of a newly planned airstrip, and, with a majestic sweep of the hand, declared "the Arctic Circle!" Lots of smiles, handshakes and photography ensued and it was one satisfied tourist that returned to Germany with his quest successfully concluded.

Meanwhile, I was once again feeling like a cad and vowed this was the last time that this particular surveyor would engage in misleading the public. I pledged that before we left Allakaket I would monument the true location of the Arctic Circle to atone for my former sins. Problem was, we didn't have an Internet connection and had no means to research the precise latitude. So I called my friend Eric Gabrielson, a surveyor in Fairbanks, and begged a favor--could he research the exact latitude of the Arctic Circle and call me back in a couple of days? Eric said sure, no problem.

Days went by; no answer. Eric wouldn't even return my messages. When I finally managed to reach him he was in a noticeably sour mood, "Look, I know you're not going to want to hear this, but I can't find that latitude. I've spent a week researching twenty different sources and have found ten different answers. There is no fixed location. It moves. End of story." I pleaded for a value, any value, something was better than nothing. After all, the State of Alaska had recently constructed a tourist wayside marking the Arctic Circle on the Dalton Highway (route of the Ice Road Truckers), and people come from the world over to have their pictures taken while standing on it.

Eric eventually relented and produced a value based on an average of the best information he could put together. With differential GPS our crews could nail this latitude to within a centimeter, so off we went. Before long we had the Arctic Circle scratched onto the surface of a gravel road near the edge of the village. Alongside was a convenient utility pole, so we attached our wooden sign that was lettered with the only color paint we had, florescent orange. We then oriented our total station due East and West to see if the line intersected anything interesting.

Indeed it did. The Arctic Circle transected Henzie Jr.'s outhouse, dead center. Henzie Jr. was a pretty cool local guy whom we had hired earlier as a trainee. After we had explained the significance, he beamed with pride knowing that he was probably the only person in the entire world whose daily ritual consisted of squatting over such an important line of demarcation.

Years passed by without giving this subject any further thought until the summer of 2009. We were working in the village of Fort Yukon, which, coincidentally, enjoyed quite a bit of tourist traffic based on the fact that the town was located "near the Arctic Circle". I asked around and discovered that, unlike Allakaket, where the people were clueless, here everybody claimed to know the position, which was "about six miles south of town . . . and you can't get to it except by boat [on the Yukon River]."

This time we had an Internet connection so I booted up Google Earth just to check. I was surprised to find that the latitude we used in Allakaket was not located six miles south of town, but much closer, actually crossing a village street. With evidently too little forethought for unintended consequences I mentioned this to a couple of people. Word got around, and within a day or two all kinds of folks were getting fired up with dreams of building some kind of tourist attraction to mark the spot. Of course, they wanted yours truly to show them the location. As Yogi Berra put it so well, "It was déjà vu all over again."

The ball was in our court and there was no escape. Within minutes I understood why my friend Eric Gabrielson grew grey hairs performing this investigation nine years earlier. Type Arctic Circle +latitude into Google and be prepared to be smothered with a ton of inaccurate, misleading and conflicting information. With no alternative I kept at it and eventually linked up with some reliable sources, including the U.S. Naval Observatory.

This is what I learned: the Arctic Circle, for all practical purposes, is a line whose position can never be exactly nailed down. By definition the position of the Arctic Circle depends on the tilt of Earth's axis relative to the plane of its orbit around the sun. To most people it is known as line where the sun never sets on June 21, the summer solstice, and where the sun never rises on December 21, the winter solstice. But here's the problem, the tilt of the earth is in a state of constant flux being subject to the influence of a number of celestial and terrestrial events.

First, there is the Milankovitch Cycle, a long-term wobble in the earth's spin that causes the axial tilt to fluctuate between about 22.1 degrees and 24.5 degrees with a 41,000 year periodicity. This, by itself, is currently causing the Arctic Circle to migrate towards the North Pole by about 15 meters per year. Then there is the Chandler Wobble, which has a periodicity of 433 days and adds to or subtracts from the progression of said Milankovitch Cycle. Then there are the other known components of nutation, which, according to the Naval Observatory, are currently composed of "106 non-harmonically-related sine and cosine components, mainly due to second-order torque effects from the sun and moon, plus 85 planetary correction terms." Not to mention the fluctuations caused by the internal motions of Earth's liquid core, earthquakes and the melting of snow and ice in the Northern Hemisphere in spring, etc., etc., which are not predictable and can only be monitored by observation.

The arcane formulas to calculate or predict these various wobbles are more than enough to cause a good headache. I found much smoother sailing when I typed "obliquity calculator" into Google.

Turns out, the "six miles south of town" response that most locals had fixed in their minds made sense. Fort Yukon began as an outpost of the Hudson Bay Company and was originally thought to be located in Canada. That's until Capt. Charles Raymond, U.S. Army Corps of Engineers, made his way upriver in 1869 to observe an eclipse of the sun and calculated that the fort was actually located within the newly purchased Alaska Territory. Besides raising the flag and booting out the Canadians, Capt. Raymond also noted the proximity of the Arctic Circle six miles to the south, a fact apparently preserved by oral tradition for nearly 150 years.

With the current estimated location keyed into a handheld GPS I set out on a bicycle and within a few minutes regrettably discovered that the Arctic Circle now crossed at a somewhat dismal location likely to be unappealing to tourists. Fortunately, a few hundred feet away was a nice little clearing with a view of the mountains and, better yet, intersected by a vintage East-West cleared line marking the boundary of a long abandoned military installation. Without hesitation I moved the marker to this spot. After all, like a broken clock, this particular point would be absolutely correct at least twice every 41,000 years--why get carried away?

When members of the village and city councils traveled with me later that afternoon to inspect the site, they stepped out of the truck in wonderment and looked down the cut line. "Wow," exclaimed one of the girls, "you can see it!"

Eric Stahlke is the Survey Manager of Tanana Chiefs Conference, an Alaskan Tribal corporation comprising 42 Native villages and based in Fairbanks, Alaska. A surveyor for 41 years, he specializes in managing project level surveys in the Alaska bush for both government and corporate clients.

Sidebar:
Capt. Charles Raymond
U. S. Army Corps Of Engineers
Excerpts from the captain's journal: Reconnaissance of the Yukon River


"During the journey the closest attention was paid to the proper transportation of our instruments. the chronometers were placed in a strong basket padded with felt and hair, ...they were transported on one of the large boats which we had in tow, in order that they might not be subjected to the constant jarring of the steamer. the smaller instruments were kept in the wheel-house."

"By an unfortunate occurrence on the river, however, our endeavors were nearly frustrated. During a stormy night, some of the men who had to sleep on deck, exposed to the weather, conceiving, perhaps with reason, that their bodies had quite as good a right to protection as my boxes, removed the instruments from their shelter, and placing them near the furnace, disposed themselves in their place. On our arrival at Fort Yukon I found that considerable mischief had been done. two of the seven threads had been broken from the reticule of the transit instrument, and both of the levels of the zenith telescope were utterly ruined...evaporated."

"As soon as I discovered these injuries I set about repairing them. having procured some fresh thread from a spider, I made a little frame of paper, with a handle bent vertically, and fixing the line to it, lowered them into position, adjusting them with my pocketmicroscope, and finally securing them in place, by means of a little shellac varnish.... After a great many trials, I finally succeeded in adjusting them to my satisfaction...."

A 1.273Mb PDF of this article as it appeared in the magazine—complete with images—is available by clicking HERE

 
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