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LIDAR lets scientists map larger areas of the sea floor in less time than multibeam or side scan sonar, but LIDAR only works in clear water.

A lot of the ocean is not clear. That's why scientists can’t use LIDAR in a lot of places.


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Bathymetric LIDAR is flown from a plane that sends out red and green laser toward the surface of the water
The plane sends out red and green laser light to the surface of the water. The red laser is reflected back from the water surface, while the green laser goes through the water and is reflected back by the sea floor. Scientists use the difference between the two lasers to calculate the water depth.

What Other Tools Do Scientists Use to Map the Sea Floor?

Another tool that surveyors use to map the sea floor is LIDAR.


LIDAR stands for Light Detection and Ranging. LIDAR sends laser light from the bottom of an airplane to the sea floor.

The light reflects back to the airplane.

LIDAR measures the time it takes for the reflections to return to the airplane.

Did you know?

Kids participating in World Hydrography Day
Kids can participate in World Hydrography Day.

The first annual World Hydrography Day was celebrated on June 21, 2006. Help spread the word about the importance of sea floor mapping every year on June 21. 

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