Depth sounding

High school (ages 12+)
Geography

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/depth-sounding

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What is the historical method?Lead line sounding, a direct measurement using a weighted rope or wire
2. What is the key applications?Maritime navigation, geological surveys, oceanographic research, environmental monitoring, and resource management
3. How did people measure ocean depth before sonar?Before sonar, sailors lowered a rope with a heavy lead weight, called a lead line, until it touched the sea floor. They counted marks on the rope to estimate the depth, but it was slow and sometimes inaccurate.
4. What is a single-beam echo sounder and how does it work?A single-beam echo sounder sends one sound pulse, or "ping," straight down. It waits for the echo from the bottom and uses the travel time to calculate depth.

Depth sounding: The measurement of the depth of a body of water, a fundamental aspect of hydrographic surveying.
Sonar: Acronym for SOund Navigation And Ranging; a technique using sound propagation to navigate or detect objects underwater.
Bathymetry: The measurement and mapping of the depth of the ocean floor or other bodies of water.
Multibeam echo sounder: An acoustic instrument that emits multiple sound beams to map a wide area of the seafloor simultaneously.