DM-51 - 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