LAT (Lowest Astronomical Tide)
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"LAT" in sailing primarily refers to Lowest Astronomical Tide, the lowest theoretical tide level, used in maritime navigation for safety to ensure water depth is rarely lower than charted. It is also commonly used to mean Latitude, which is the angular distance (in degrees/minutes) of a vessel north or south of the Equator.
Key Aspects of LAT (Lowest Astronomical Tide):
Safety Standard: Used on modern nautical charts as the datum for soundings (chart datum), providing a safe, conservative estimate of water depth.
Navigation: Helps sailors avoid grounding by ensuring that the depth shown on the chart is, in most cases, lower than the actual water level.
Key Aspects of Latitude (Lat):
Measurement: Lines run east-west, parallel to the Equator (0°), measuring position north or south up to 90° at the poles.
Distance Calculation: One minute (1') of latitude equals one nautical mile, or approximately 6,068 feet.
Usage: Used with longitude to fix a boat's position on a chart.
Key Aspects of LAT (Lowest Astronomical Tide):
Safety Standard: Used on modern nautical charts as the datum for soundings (chart datum), providing a safe, conservative estimate of water depth.
Navigation: Helps sailors avoid grounding by ensuring that the depth shown on the chart is, in most cases, lower than the actual water level.
Key Aspects of Latitude (Lat):
Measurement: Lines run east-west, parallel to the Equator (0°), measuring position north or south up to 90° at the poles.
Distance Calculation: One minute (1') of latitude equals one nautical mile, or approximately 6,068 feet.
Usage: Used with longitude to fix a boat's position on a chart.