Definition

1. Noun:
   • The average level of the ocean's surface: "sea level" refers to the average height of the ocean's surface, typically measured as the midpoint between the average high tide and the average low tide.
   • A standard reference point: It is used as a baseline or zero point for measuring the elevation of land and the depth of the sea.

Usage Examples

• Noun:
  • The city is only two meters above sea level. (The city's elevation is just two meters higher than the average ocean surface.)
  • Scientists are concerned about the rise in global sea level due to climate change. (Researchers worry about the increase in the average global ocean surface height caused by warming temperatures.)

Advanced Usage

• "Mean sea level (MSL)": The average height of the sea's surface over a long period, used as the standard reference.
  • The airport's runway elevation is given relative to mean sea level.
• "Above/below sea level": Common phrases to describe elevation or depth relative to this standard.
  • The Dead Sea is approximately 430 meters below sea level.

Variants and Related Words

• Sea-level (adj): Used attributively to describe something related to this measurement.
  • The report studied sea-level rise in coastal communities.
• Sea-level datum: A specific, fixed reference point for sea level measurements.

Synonyms

• Water level: (Can be synonymous in specific geographical contexts, though less precise.)
• Ocean surface: (Refers to the physical surface, not specifically the averaged standard.)

Related Phrases

• Relative sea level: The sea level measured relative to the local land, which can change due to land sinking or rising.
  • Relative sea level rise is a major threat to this sinking delta.
• Global sea level: The average height of all the world's oceans combined.

Related Concepts

• Elevation: The height of a point above or below sea level.
• Bathymetry: The measurement of water depth, often from the sea level baseline.

Noun

1. level of the ocean's surface (especially that halfway between mean high and low tide); used as a standard in reckoning land elevation or sea depth