What is the purpose of using a LAT-WGS84 ellipsoid separation model?

Using a LAT-WGS84 ellipsoid separation model serves a crucial function in hydrographic surveying by relating data to chart datum accurately. The separation model provides the necessary adjustments to transform geoidal heights (which are based on the Earth’s gravitational field) into ellipsoidal heights (which are based on mathematical models of the Earth). This is essential for ensuring that survey measurements align with standard chart datums, specifically Lowest Astronomical Tide (LAT), which is vital for maritime navigation and safety.

Accurate relation of survey data to established chart datum allows for consistent depth readings and reliable navigation. Without a proper separation model, discrepancies could arise between the actual water depths measured and what is presented on nautical charts, leading to potential hazards for vessels navigating these waters. Thus, the integration of the LAT-WGS84 ellipsoid separation model is fundamental to maintaining the accuracy and safety of hydrographic data.