Everything You Know How Deep Is The Ocean
water covers about 71% of the Earth’s surface. That liquid takes up more than 332,519,000 cubic miles of that total surface, or 1,386,000,000 cubic kilometers.
The official website of the National Oceanic and Atmospheric Administration says there’s enough water in the ocean to fill about 352,670,000,000,000,000,000 gallon milk containers!
Now let’s assume you don’t have that many milk containers. Here’s another amazing image: theoretically, you could cover the entire United States (yes, Alaska and Hawaii included) in ocean, with a water column more than 82 miles (132 kilometers) high.
Not surprisingly, some of the most common questions about the ocean concern how deep it is. How deep is the ocean? Where is its deepest point located? What is its average depth?
Today you’ll learn the answers to these questions about the deep ocean, and the bonus is that you don’t even need to pack your scuba gear.
What is Average Ocean Depth?
Technically, Earth has only one ocean. So, somewhat confusingly, five major regions within this vast body of water are all called “oceans”: the Pacific, Atlantic, Indian, Arctic, and South China Seas.
Together, these regions make up what’s known as the “global ocean.” When people talk about “the ocean” as a whole, this is what they usually mean. (It’s also what we meant in the two hypothetical scenarios we described earlier.)
Of course, the depth of the ocean isn’t uniform. It varies greatly depending on geographic location. At any random point on a map, the distance between the seafloor and the surface of the water above might be affected by underwater valleys, mountains, or a variety of other features.
Using tools like sonar, radar, and satellite technology, scientists have calculated that the how deep is the ocean is about 12,785 feet (3,897 meters). That’s about 2.4 miles, or 3.8 kilometers.
What is the Deepest point in the ocean?
The Mariana Trench is deeper than Mount Everest. The deepest point in the Arctic Ocean is called Challenger Deep, named after the British naval ship Challenger, which discovered the Mariana Trench in 1875. The samples collected by the Challenger crew laid the foundation for deep-sea research. VectorMine/Shutterstock
We can also compare different sites. A 2019 study published in Earth Science Reviews used existing data and research to divide the deepest areas in five sub-regions of the world’s oceans. Here’s what the researchers found:
The deepest point in the Arctic Ocean is Molloy Hole. It is 18,599 feet (5,669 meters) below the surface.
The deepest point in the Indian Ocean? According to the study authors, it is most likely an unnamed part of the Java Trench, which is 23,917 feet (7,290 meters) below the water. As for the Southern Ocean, which surrounds Antarctica, its deepest point is in the South Sandwich Trench, which is 7,385 meters (24,229 feet).
The Puerto Rico Trench, also known as the Milwaukee Abyss, is 8,408 meters (27,585 feet) deep, making it the deepest point in the Atlantic Ocean.
“But wait!” you might say. “What about the Pacific Ocean?” Don’t worry, we saved the best for last. East of the Mariana Islands in the Pacific Ocean, there is a deep undersea rift that has fascinated adventurers and science fiction writers alike.
It’s called the Mariana Trench, and it’s not only the deepest point in the Pacific Ocean, but also the deepest point in the entire world’s oceans, a location that’s marked on our maps as Challenger Deep. The trench is located in the western Pacific Ocean.
Measuring its exact depth has always been difficult, but a more conservative estimate, supported by a 2019 study, puts the seafloor here at a whopping 35,843 feet (10,925 meters).
How deep is Challenger Deep? Quite deep. In fact, this point in the Pacific Ocean is deeper than Mount Everest. The summit of this landmark in the Himalayas is only about 29,026 feet (8,848 meters) above sea level. The movement and interaction of Earth’s plates formed these steep trenches, as well as the tallest mountains.
What techniques are used to measure the depth of oceans such as the Mariana Trench?
Modern techniques for measuring ocean depth include sonar mapping, which uses sound waves to detect features on the seafloor, and deep-sea submersibles equipped with pressure-resistant depth gauges. Satellite altimetry, which measures surface outcrops in deep water, also provides indirect measurements of depth.
How does deep-sea exploration impact our understanding of terrestrial biology?
Exploring the deep ocean can uncover unique ecosystems, such as hydrothermal vent communities, that thrive in harsh conditions without sunlight. These discoveries contribute to science and conservation efforts by expanding our understanding of biodiversity, biological resilience, and the potential for life in extreme environments.
