Thursday, April 23, 2009

More errors

And this one is serious - the Four Corners marker is in the wrong place!

According to readings by the National Geodetic Survey, the Four Corners marker showing the intersection of Arizona, Colorado, New Mexico and Utah is about 2.5 miles west of where it should be.

Update from ABC:
Four Corners marker off by only 1,807 feet

Doyle said some confusion over how far off the monument is from the "true" Four Corners has stemmed from how it's measured.

The measurement should be taken as 32 degrees longitude west of the Washington Meridian, which passes through the old Naval Observatory in the Foggy Bottom neighborhood of Washington, D.C. That calculation yields the 1,800 foot disparity.

Measuring instead to the 109th meridian west of Greenwich would suggest a much larger difference of about 2.5 miles.

* snip*

Besides, the measurement differences don't matter anymore, Doyle said, because "the monument controls."

"Where the marker is now is accepted," Doyle said. "Even if it's 10 miles off, once it's adopted by the states, which it has been, the numerical errors are irrelevant. It becomes the legal definition" of the Four Corners.

Thanks to the Maps-L listserv

1 comment:

Cranberry Necklace said...

I hope some of the map spots I have blindly placed in my census work (when the visual of the map has not displayed because the handheld computer with GPS in it is on the fritz) do not become the legal definition of where the residences I'm documenting actually exist! I'm trying my best, but the equipment fails in cold, wet weather; and Cleveland in April is usually cold and wet. Good enough for government work is just the best I can do with what I have at the moment. I hope the government plans to do successive approximations to improve the data, rather than leaving the imperfect data I've collected as "the truth."