Professional Use Boundary Canon

Primary evidence for spatial responsibility and boundary validation.

Global Consensus: Prohibition of Web-Map Boundary Use

The following authorities share a consistent, global consensus: Web-based maps and non-geodetic spatial tools are referential and carry no legal authority for professional use.

Authority Body Stated Limitation Reference
Google / Tech Assumption of user risk; actual conditions differ. View Canon
USGS / National Not the legal record; no authority for boundaries. View Canon
NGA / Defense Unacceptable for mission-critical operations. View Canon
GSI / OS / Regional Positional variation; no responsibility accepted. View Canon
Official Wording: Google Maps / Earth TOS
"When you use Google Maps/Google Earth's map data, traffic, directions, and other content, you may find that actual conditions differ from the map results and content, so exercise your independent judgment and use Google Maps/Google Earth at your own risk."

Primary Source (External —Content maintained by the originating authority):

https://www.google.com/help/terms_maps/
Official Wording: NGA Operational Advisory
"the use of Web Mercator and other non-WGS 84 spatial reference systems may cause geo-location / geo-coordinate errors up to 40,000 meters. ... This erroneous geospatial positioning information poses an unacceptable risk to global safety of navigation."

Primary Source (External —Content maintained by the originating authority):

NGA Advisory via GPS World
Official Wording: Regional Mapping Authority (GSI / OS)
"It is not possible for Ordnance Survey to replicate the exact position of each physical feature on the ground. ... No responsibility can be accepted for any actions carried out by users using information on this website [GSI]."

Primary Sources (External —Content maintained by the originating authorities):

GSI (Japan) OS Summary (UK)

Responsibility Verification Required

Presence of these coordinates does not constitute professional validation. You must reconcile these outputs against the Citation Canon above before use in legal or engineering projects.

Return to Coordinate ツール一覧 →

US State Plane (SPCS) Converters & Local Guides

Professional engineering and surveying transformations from state-specific conformal grids to GPS WGS84.

専門家による測地検証済み
専門的な測地基準に準拠して検証済み

The $50,000 Geodetic Drift Liability: NAD83 vs WGS84

北米プレートは年間約2cm移動するため、NAD83(2011)とWGS84(G1762)は現在2.2メートル以上乖離しています。 高精度なNAD83地籍杭打ちに「標準的な」GPS WGS84座標を使用したことで、基礎のやり直しやインフラの配置ミスによる5万ドルの専門家責任賠償請求が発生しています。

Risk Exposure Metric: 2.2-Meter Tectonic Drift & Epoch Accumulation