Everest’s Height Was Historically Determined

Bilko von Hartenberg’s new book, Sea Level 0 Meters, traces the history of how humans established a baseline for measuring altitude. The book details how practical needs drove early sea level measurements.

In 1440, Venice gauged water depth by looking for dark algae on building foundations. Amsterdam began recording sea levels in 1556 to prevent flooding.

The French Royal Academy of Sciences first distributed official guidelines for measuring sea level as a central administrative body. Establishing a consistent standard proved difficult, requiring debate and revisions.

The book argues defining sea level wasn’t simply a scientific endeavor. It connected to the way modern nations organized and controlled the world, including canals, ports, and colonies.

From 2011 to late 2022, global average sea level rose roughly 5 centimeters, a change not felt equally across all regions. Coastal areas and islands now experience the direct impact of rising waters. The work of understanding and measuring sea level continues as the planet changes.