How do you research and explore the deep ocean?


Exploring the deep ocean is a tricky business.


The most immediate barrier is its darkness. Beneath 1000m, it is entirely dark and even in the ‘Twilight’ or mesopelagic zone below 200m, there is very little natural light and little that scientists can do without introducing artificial light sources.


The more pressing problem (literally) is pressure. Humans can only travel into the deep ocean in hollow pressure hulls of extraordinary strength.

Life in the deep ocean lives under pressure. On land we are subjected to pressure from the air around us of around 6.5 kilos (14.5 pounds) per square inch – known as ‘one atmosphere’. The deeper you go in the ocean the greater the pressure becomes.  For every 10 meters of additional depth, the pressure increases by ‘one atmosphere’.  Marine creatures such as whales deal with these rapid pressure changes by having highly flexible bodies which can collapse to absorb the change but for a human, the pressure in the deepest ocean would be the equivalent of trying to hold up 50 jumbo jets. At the deepest point, approximately 11km down, the pressure is 1200 atmospheres - 1 million kilograms per square metre (18,000 pounds per square inch) – a bull elephant on your smallest toe.

Humanity’s journey down… from the first deep dives to full ocean depth:

The first submersible dives to the deep ocean took place in June 1930 when William Beebe and Otis Barton descended below 400m in a bathysphere near Bermuda.

‘Anyone who has actually seen this universe will keep an image of it in his memory forever, for its isolation, its cosmic cold, its eternal obscurity - and above all, for the indescribable beauty of the denizens of those regions”

William Beebe, 1935

In 1960, US Navy Captain Don Walsh and the Swiss engineer Jacques Piccard (father of the explorer Bertrand Piccard), achieved the ultimate feat, descending in the bathyscaphe Trieste to Challenger Deep, the deepest point in the Marianas Trench. The US Navy gave it the codename ‘Project Nekton’. No human had been back until film-director James Cameron repeated the dive in 2012.

“By breaking the seal of the surface, penetrating the mirror that reflects the sky, and entering the watery inner space, man will reap a bountiful and incredible harvest in the decades ahead. We are to speak of conquering nature. If man has a weakness, it is this vanity. The best we can hope to do is to understand nature and obey it”. Jacques Piccard

Since 1960, several governments and university scientists have begun scientific research programmes in the deep ocean. However, relative to the size and significance of the deep ocean ecosystem, the world’s submersible fleet and capabilities have far to go. There are currently only five government run and owned submersible scientific programmes in various states of activity:

1.     Pisces IV and Pisces V2000m, 2-person, Hawai’i Undersea Research Laboratory (HURL), USA, Commissioned: 1980. 

2.     Alvin: 4500m, 3-person, Woods Hole Oceanographic Institute (WHOI), USA, Commissioned: 1964, Refit 2014.

3.     Nautile: 6000m, 3-person, French Research Institute for Exploitation of the Sea (IFREMER), France, Commissioned: 1984.  

4.     Mir 1 and Mir 2: 6000m, 3-person, P. P. Shirshov Institute of Oceanology (PPSIO), Commissioned:1987.

5.     Shinkai 6500: 6500m, 3-person, Japan Agency for Marine Earth Science and Technology (JAMSTEC), Japan, Commissioned: 1989. Jialong: 7000m, 3 person, China Ship Scientific Research Center (CSSRC), China, Commissioned: 2009.