DM-51 - Vertical datums

You are currently viewing an archived version of Topic Vertical datums. If updates or revisions have been published you can find them at Vertical datums.

Learning Objectives: 
  • Explain how a vertical datum is established
  • Differentiate between NAVD 29 and NAVD 88
  • Illustrate the difference between a vertical datum and a geoid
  • Illustrate the relationship among the concepts ellipsoidal (or geodetic) height, geoidal height, and orthometric elevation
  • Outline the historical development of vertical datums