Last seen: May 28, 2026 2:28 pm
The only way to get real WGS 84 values is to perform an autonomous position just with respect to the satellite constellation, in which case your posit...
The use of the term "international" for the foot is derived from the 1959 Federal Register Notice by the Bureau of Standards (now the National Institu...
August 17, 2007 --
The Table 1 from the POB article is not entirely up to date. Before retiring from NGS I was the keeper of all things dealing with State Plane Coordin...
Considering the limited number of GPS on bench marks in the NGS database that contributed to GEOID12A (or any other previous model for that matter) 8 ...
Both NC and FL have done that. You would need to contact the Denver USGS office to see about getting copies of the horizontal and vertical data. Thi...
Before I retired from NGS we had a near complete collection of the old USGS horizontal and vertical control data and it was easy to get to and respond...
USGS Publications (historic)Dead on as always Loyal 🙂
USGS Publications (historic)I live in Silver Spring, MD 6.3 miles from the NGS office.
WGS 84 geoid heightsFranz,If there are a lot of GPS on BMs in Singapore than the mapping authority should have the data needed to compute a hybrid geo...
States using International foot plus conversion factorsGeeOddMike's list is correct with the exception of Utah - they rescinded the International Foot...
USGS Publications (historic)I was the geodetic liaison to the Cartographic Section when they were disbanded. I later worked for "Fast Eddie" McKay (a ...
USGS Publications (historic)The Geodetic Control Diagrams (GCDs) and the associated insert diagrams were always produced by USC&GS/NGS. They were...
As Mike said ET = Electronic Traverse. This was used by USGS. In addition to TT they also used PTS = Primary Traverse Station. Some (just a few) US...
Contact Tim Smith ([email protected]). Tim in the Park Service GPS program manager. If he doesn't have the data he should be able to point you direc...
HTDP & phantom vertical movementAnd now you see some of the issues with building a VTDP tool - what are the real subsidence rates. Vertical movem...
HTDP & phantom vertical movementAs mentioned previously, NGS does not yet have a VTDP tool. That being said you can estimate the vertical velocit...
NGS does not have a VTDP tool at this time. This is an area that was getting considerable attention and then several retirements that hit NGS a coupl...