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How Deep is the Ocean REALLY?

Nothing causes big mysterious waves quite like our oceans. Covering over 70% of the world’s surface
and providing depths upon depths of exploration for divers, let’s find out just how deep our oceans
really are.
The Shallow End
Thousands of explorers dive deep in the ocean to get a look at some of the most beautiful creatures
in the world. The official scuba-diving limit is 100m – that’s bigger than the size of Big Ben!
A diving limit was put in place because with every 10m under the water, the pressure rises by one
atmosphere. This means that at 50m the pressure is actually FIVE times higher that it is on the
surface. The pressure is caused by water pushing down on a diver and humans can safely withstand
3 to 4 atmospheres of pressure – that’s a maximum of 40m beneath the surface.
The pressure affects the oxygen tanks that scuba divers carry, and can affect their breathing. Most
diving associations don’t allow recreational divers to go deeper than 60m for safety reasons.
Seeing in the Sea
The ocean is split into three different zones, based on its depth and light: euphotic (sunlight),
dysphotic (twilight), and aphotic (midnight).

  • Euphotic: The upper level of the ocean – which is closest to the surface – receives the majority of
  • Dysphotic: Found between depths of 200m and 1,000m, the intensity of light rapidly decreases as
    the ocean’s depth increases. Due to only a small amount of light being able to penetrate beyond
    these depths, photosynthesis is impossible.
  • Aphotic: The third zone – which reaches depths below 1,000m – does not receive any sunlight, and
    waters at this depth are bathed in darkness.

Famous Dives
In 1947, Maurice Fargues reached a depth of over 120m and was the first diver to die whilst scuba
diving. The diving volunteer carved his signature in a rock before losing consciousness. The reason
for his dive was to establish the safe diving limit for future divers. The depth Fargues reached is two
times as tall as the leaning tower of Pisa.
The deepest dive ever made with scuba-diving gear was completed by Ahmed Gabr in 2015. He
dived to an astonishing depth that is the entire length of the Eiffel Tower – that’s 324m!
Deep Sea Creatures
The deeper we delve into the depths of the ocean, the more fascinating the waters become. At
1,500m below the surface, you will find creatures such as the frilled shark – the oldest living species
of shark.
Only discovered in 1976, the megamouth shark resides at these depths too, which is why scientists
are still having trouble classifying this creature. We may not know much about this species of shark,
but we know a lot about its friends – have a jawsome time discovering all seven of our shark
displays .
At an astonishing depth of over 3,000m, the deepest whale dive was recorded by a Cuvier’s beaked
whale – that’s the same length as eight Empire State Buildings.
The Deep Blue Sea
The deepest, darkest, most mysterious place on earth: the ocean floor. Almost an astonishing
11,000m below the surface, the Mariana Trench is the deepest part of the ocean. It is around THREE
times the length of the Hollywood Walk of Fame – now, that’s a long, long way to get a picture with
Dolly Parton’s famous star.
Located in the Pacific Ocean, Mariana Trench was first discovered by the British Royal Navy in the
1870s. Due to its depth and its atmosphere pressure, humans were unable to explore the ocean’s
floor until 1960, when a purpose-built bathyscaphe called Trieste was made. The journey took five
hours, and the explorers were only allowed to stay there for 20 minutes.
The second and only other time people have visited the Mariana Trench was in 2012. Famous for his
ocean direction in the hit film Titanic, there was no time for letting go as director James Cameron
spent around three hours on the ocean floor. Using a deep submergence vehicle (DSV) called Deep
Sea Challenger, the ocean descend was two times faster than the previous dive.
Dive Right In
Did you know that over 500 people and six different species of animals have been to space, yet there
has only ever been TWO trips to the deepest part of the ocean?
Fancy diving into the deep and having an underwater adventure like you’re in your very own
Mariana Trench? Swim on over and walk our Ocean Tunnel and start your exploration of the biggest
mystery in the world – the ocean.

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