Culture Online


How much pressure builds up at the deepest point in the ocean?

That is a very cool question! Thanks for sending it in!

I should probably start by introducing you to the deepest point in the ocean – Challenger Deep in the Mariana Trench (see the map and photograph below).

graphic image of a map of the world. There is text in large black font saying Mariana Trench with an arrow pointing towards an area marked in red in the shape of a thin crescent. The area is in the Western Pacific Ocean between Japan and Papua New Guinea.

Challenger Deep in the Mariana Trench is around 11,000 metres below the sea surface – that’s deeper than flipping Mount Everest upside down!

Photograph of a yellow, cylindrical shaped underwater vessel. The top of the photograph is black from the darkness. There are lights shining from the vessel which illuminate the bottom of the sea floor bed which is white with a few rocks.

To imagine how deep this is, I would recommend watching this video:

It also shows some of my favourite ecosystems – hydrothermal vents – so keep an eye out for those and the eyeless shrimp that live there!

Right, now you know where the deepest point in the ocean is, I can answer your question…  

… the bottom of the Mariana Trench has 1,086 bars of pressure.  Bars are a unit for measuring pressure, like how we use degrees Celsius to measure temperature.  Sometimes pressure is also measured in ‘psi’ (and in the deepest point in the ocean, it is 15,750 psi).  But what does this mean to us in the real world?  Well, it’s hard to imagine.  So, whilst that is the answer to your question, perhaps it is helpful to know that the pressure at the bottom of the deepest point in the ocean would feel like 100 adult elephants standing on your head!  That’s a lot of elephants!
I hope that helps to answer your question.  

A portrait photograph of an adult elephant. The elephant is looking straight on at the camera and has large tusks. The sky in the top half of the image is blue and the ground in the bottom half of the image is dusty grassland.

I have one more cool fact to share with you to do with ocean pressure… 

… Did you know that deep-sea scientists often send coffee cups down to the bottom of the sea on deep-sea robotic vehicles, so they have a souvenir from their research trip?  The pressure makes the cups shrink before they come back up to the surface!  Here are some examples of the normal cups to the left (which the scientists decorate with information about the research dive) and the ones that have been to the bottom of the sea to the right:

Look how much they shrink with the pressure!  

I think that’s pretty cool and I hope you do too!  Have a good day!