Many organizations use geodesy to map the U.S. shoreline, determine land boundaries, and improve transportation and navigation safety

Coastal marine transportation

Safe and efficient marine transportation is one of the many benefits of geodesy.

Geodesists assign coordinates to points all over the Earth. Using the Global Positioning System (GPS), geodesists can accurately define the coordinates of points on the surface of the Earth in a consistent manner. This set of accurately measured points is called the National Spatial Reference System (NSRS), which allows different kinds of maps to be consistent with one another.

Developers, local officials, city planners, and many others use the National Spatial Reference System to determine land boundaries for development or conservation efforts. Government agencies also rely on the NSRS to update maps of the U.S. shoreline.

Geodesy is also critical to the transportation industry. Surveyors use the National Spatial Reference System as one of their tools to develop nautical charts. Mariners use these nautical charts and GPS to accurately position their ships. This technology, accurate down to a centimeter scale, allows mariners and commercial vessels to assess where the bottoms of their ships are relative to the bottom of the ocean. With this information, a ship can hold extra cargo, sinking deeper into the water, and still safely navigate through a channel. The ability to move more cargo at a time is direct economic benefit to the shipping industries and ultimately to the consumer.

In addition, geodetic data, specifically datum information, and water level data are critical for agency officials to properly plan, design, and engineer coastal restoration projects. These data provide baseline information that assist in the construction of phases of marsh restoration projects, for example.

Geodesy is the science of measuring and monitoring the size and shape of the Earth, including its gravity field, and determining the location of points on the Earth’s surface.

For more information:
National Geodetic Survey
National Spatial Reference System
Geodesy (audio podcast)
Geodesy Tutorial, NOS Education