How deep is the ocean? Interesting facts

Have you ever wondered how deep the ocean is? Or what is the deepest place on earth? As divers, we should know such interesting facts. Today I will take you into the deep (very deep) world of the ocean.

The ocean has always been the focus of many people and different subjects: visual artists, merchants, military men, mythologists, painters, singers, athletes or romantics. Despite its power and unpredictability, it has always magically attracted people.

As humanity, we have always wanted to explore the unknown, and in the 21st century, there are few undiscovered places left on Earth. However, things are different under the water’s surface. One of the interesting questions is how deep the ocean is.

What can you find in this post?

Oceans, seas, lakes – all this water covers as much as 71% of the Earth’s surface. That’s a lot, and we know so little about the oceans and their inhabitants.

Today we’re going to talk about how deep the ocean is, which animals are the most persistent when it comes to reaching depths, and what else we have to discover.

When did people become interested in the oceans?

Surely you know the story of Christopher Columbus and his discovery of America. Now we know that he was not the first visitor from the western world to set foot in America. We know that before Columbus, there were already Vikings here, led by Leif Erikson.

And they may not have been the first ones here either…. It just goes to show that mankind has been using the ocean for centuries, learning to understand it and use it for their purposes.

The history of scientific ocean exploration can be traced back as far as 1200 BC, when Phoenicians began ocean voyages using celestial navigation. I’m sure they’ve wondered more than once how deep the ocean they’re sailing on is.

First measurements of ocean depths

The science that deals with measuring the depth of water is called bathymetry. It is a branch of hydrology that deals with measuring the depth of watercourses and bodies of water. Nowadays, various measuring devices, pressure probes, acoustic probes and even satellites are used for measurements.

These devices are very precise and provide accurate data. The results of these measurements are usually presented on bathymetric maps. Looks complicated? Then how about the fact that the first documented evidence of water depth measurements dates back to ancient Egypt over 3,000 years ago….

As I mentioned earlier, people have always been fascinated by the ocean and wanted to know the answer to how deep the ocean is.

Today we know that the average depth of the ocean is about 3.7 kilometers (or 2.3 miles)

So what is the deepest place on earth?

You already know that people have long been interested in the depth of the ocean. You also know that we now have the technical ability to make reasonably accurate measurements. So what currently known place is considered to be the deepest on earth?

How deep is the ocean?
How deep is the ocean?

The Mariana Trench

This place is located in the western Pacific Ocean, about 200 km (124 miles) east of the Mariana Islands.

The Mariana Trench was discovered during the Challenger expedition in 1875. Then, using a very simple method, i.e. a rope with a weight, it was discovered that the depth in this place reaches 8184 meters (26 850 feet).

A few years later, in 1899, another expedition has determined the depth of this place at 9,636 meters (31,614 feet). You have to admit that these are really admirable results, especially with such simple tools.

The Challenger Deep

There is one particular point in the Mariana Trench that is now recognized as the deepest on Earth. It is called the Challenger Deep. According to the latest data, the Challenger Deep is 10,994 m (36 069 ft) ±10 m (33 ft). Pretty deep, huh?

So to answer your question – how deep is the ocean – around 10,994 m.

Can’t you imagine that? Think of the tallest mountain on Earth – Mt. Everest, which is 8848 m. If we took that entire mountain and plunged it into the depths of the Challenger Deep, there would still be over 2 km from the surface of the water to the top of Everest!

How deep can we go?

We’ve already figured out how deep the ocean is. The question to ask now is whether we, as humanity, are capable of descending to such depths?

Recreational diving – max 40m

Let’s start with the diving equipment. After completing a basic scuba diving course, you will be licensed to 18m, and in recreational diving the maximum depth is 40m. This is still very far from the maximum depth of the ocean. Diving to this depth with this set of equipment will not work.

Technical diving – max 332m

In 2014. Ahmed Gabr dived to a depth of 332.35 m (1,090 ft) and thus made history as the first person to dive that deep. It was a bravura performance and we probably won’t see another daredevil anytime soon. Still… it was only 3% of the maximum depth of the ocean…

Serious military equipment – up to 700m

An ADS (atmospheric diving suit) is a rather small underwater vehicle that allows one to theoretically dive to depths of up to 700 m without feeling the effects of such depth.

Atmospheric diving suit
Atmospheric diving suit

Deep dive simulation – 701m

In 1992, a simulated plunge to a depth of 701 m was performed in a suitably prepared hyperbaric chamber. Theo Mavrostomos was subjected to conditions and pressures that prevail at such a depth and came out alive.

So we can assume that theoretically we are able to dive to a depth of 700 meters. This is an incredible depth that I can’t imagine, but it’s still very far from the maximum depth of the ocean!

Can we go even deeper?

Yes, but it won’t have much to do with diving anymore. In 2012, James Cameron (yes, the guy from Avatar) descended to a depth of 10898.42m (35756ft) in the Deepsea Challenger.

However, many years before him, in 1960 Jacques Piccard and Don Walsh descended to a depth of 10910.92 m (35797 ft)

James Cameron in Deepsea Challenger
James Cameron in Deepsea Challenger

Why can’t we just dive that deep?

Well… there are many reasons, but the main one is the increase in pressure. At the surface there is a pressure of 1 atmosphere (more or less). But every 10 meters of water is another atmosphere. So already at a depth of 50 m the pressure will be 6 atmospheres!

Now calculate the pressure at the depth of the Mariana Trench. By the time you reach the bottom, the pressure would have long since crushed you, just as you crush an empty soda can.

Do any animals live at such great depths?

Although animals are much more capable of traversing great depths, they also have their limitations. We are unlikely to encounter animals at such great depths, unless there are still some undiscovered creatures that have adapted to such depths.

Below you can see a very cool animation about how deep the ocean is and what animals can be found in it:

Let’s recap. How deep is the ocean?

Thanks to reading our blog you already know how deep the ocean is and that there is still much to discover. You too can take part in this wonderful adventure, and it all starts with a basic scuba diving course.

If it suits you, you can come to us at costaricadivers to get your license and talk over coffee about the ocean and its mysteries. In any case, bookmark our site as we will be covering many other interesting topics on our blog. Stay tuned!