Sea Level Change: Datums and Terminology

Sea Level Change: Datums and Terminology
This lesson addresses how sea level is determined and applied. It starts with a general discussion of the surfaces that form the basis of measurement, called datums, then looks more closely at the vertical datums that form the basis of height measurements. We cover tidal datums in more depth, including the different datums, their extent, period of record (called a tidal epoch), and common applications. We conclude with a look at some data resources for tidal datums and sea level trends.