S-104, formally known as Water Level Information for Surface Navigation Product Specification, also called S-104 Water Level Information for Surface Navigation, is a time-varying tidal information product specifically designed for surface navigation. It records water level data and related metadata at different times within specific geographic areas.

The basic content of S-104 data includes: location points (specific positions), time (exact moments of water level observation or prediction), water level values (height at given time), and water level trends (e.g., rising or falling). This data format is particularly suitable for describing water level conditions at specific times and locations.

S-104 data has many important practical applications, especially in maritime navigation and port management, such as:

• Port entry/exit navigation: Using S-104 data to predict tidal changes helps vessels choose optimal times for port access, avoiding grounding during low tide.

• Waterway planning and management: In complex or shallow waters, S-104 data assists port authorities and navigators in dynamically adjusting route plans to ensure safe passage under varying tidal conditions.

• Environmental monitoring and research: S-104 data supports researchers in analyzing climate change impacts on tides and monitoring coastline erosion, contributing to marine environmental studies.

S-104 Navigational Water Level Diagram

SuperMap iDesktopX supports importing S-104 navigational water level data. In this section, you will learn:

• Open S-104 data: Explains how to import *.h5 files compliant with S-104 specifications.
• Depth query: Describes how to query water depth values from S-104 navigational water level data.