How deep is the ocean?

Oliver Denker/

It is now a well-known fact that 71% of the Earth’s surface is water. However, most of us have no idea how deep the ocean really is. If you had to guess how deep it is? What would you think? 1 kilometer? 100 kilometers? 1000 kilometers? It is a question that our minds struggle to comprehend as we have difficulty grasping the vast nature of something like the ocean.

When you think about humankind, so much has been conquered. All land on Earth has now been discovered. Someone has laid claim to every piece of land there is. Space is the next area of exploration and it has already begun in places like the Moon and Mars. At times it can make you feel like there is so little unknown about our cozy little planet.

The truth is very different. While the land is well explored, the sea is still a mystery to most. When you consider that the oceans cover 71% of the surface of the earth it shows how vast and enormous they are. Unlike the earth’s surface, the oceans expand vertically down as well. There really is an incredible amount to discover.

Today we know that the ocean is on average 3.7 kilometers deep, although with huge variances, with areas closer to the land being much shallower and those in the middle of the ocean much deeper. In addition, there exist narrow trenches in the water that are small narrow openings that continue many more kilometers deep. The Mariana Trench is believed to be the deepest trench in the world (although we can’t be sure) and it measures around 11 kilometers deep

Scientists use sonar to measure the ocean depths by sending out pulses of sound and measuring how quickly they bounce back. While this is a fantastic and clever method of measuring depth it means that there are still large areas of the Earth that are yet to be measured using sonar. This suggests there could be deeper trenches out there and many more things to discover. The method is still far superior to the previous method of measuring which involved bringing a really long rope to the ocean, tying a weight to it and seeing how far down it went. This is actually how the Mariana Trench was discovered in 1872. 

For those of you looking to claim an adventure, something that remains to be discovered, the oceans await.