Maybe the folks at the Commission know something we don’t.
A recent item in the Federal Register caught our eye. According to an “informational” notice published by the National Geodetic Survey (an office within the Commerce Department’s National Oceanic and Atmospheric Administration), new realizations of the North American Datum of 1983 (you may recognize that as “NAD83”) have now been finalized. These new realizations supersede all previous NAD83 realizations.
(Possibly helpful aside: the North American Datum defines the geodetic network in North America. Geographical coordinates are based on it. The two major Datums – or should that be “Data”? – currently available are NAD27, computed in 1927 using whatever hand-crank methods were available back then, and NAD83, computed in 1983 using whiz-bang satellite technology and refined periodically since then. The smart money figures that NAD83 is probably the more reliable of the two.)
In geodetic circles, the new realizations are probably a Very Big Deal, although it appears from at least one explanatory item we found on the Internet that any variations between the latest version and its most recent predecessor involve only a couple of centimeters one way or the other.
But talk of NAD83 got us to thinking about an item we posted here more than two years ago.
There we reported on an effort by the Society of Broadcast Engineers (SBE) to get the Commission to convert CDBS to NAD83, instead of NAD27. After all, as the recent Federal Register item points out, since 1989 NAD83 has been “the official civilian horizontal datum for the United States surveying and mapping activities performed or financed by the Federal Government.” As we pointed out in our earlier post, the FAA has used NAD83 since 1992 and the FCC’s Wireless Bureau has used it since 1999.
So we looked around and could find no evidence that the Commission has taken any action on the SBE petition, which was filed in 2007 (although for some reason it wasn’t stamped “received and inspected” by the FCC Mail Room until 2011). FWIW, the SBE petition still shows up in ECFS as a pending petition for rulemaking. [Blogmeister’s Note: For an interesting glimpse into the odd “in limbo” status of numerous petitions for rulemaking such as SBE’s, check out our friend Dr. Michael Marcus’s blog post on the topic.]
The Commission’s glacial – or should that be tectonic? – pace with respect to transitioning to NAD83 is puzzling. Maybe they’re waiting for the day when CDBS is merged into the other Commission databases, another plan whose pace has seemed decidedly snail-like. Maybe it has something to do with the incentive spectrum auction, which seems to be absorbing the majority of the FCC’s energy these days. Maybe the folks at the Commission know something we don’t know about, like, maybe, some imminent topography-altering event – perhaps an impending asteroid strike, or a nationwide rash of giant sinkholes – that could render NAD83 inaccurate and necessitate the computation of a whole new NAD.
Whatever the reason, the bottom line is the same: CDBS remains tied to a geographical coordinate system which is fast approaching its centenary. We’ll keep an eye out for any changes as NAD27’s Big 100th approaches. Check back here for updates.