The Ultimate List of Underwater Fun Facts

In our opinion, the ocean is one of the most astonishing and mysterious places on Earth. Of course, this only means there's a mountain of cool facts about it! We decided to compile a list of fun facts about the ocean that you (probably) didn't know. When you are doing your scuba diving course remember these facts and use them to impress your instructor and fellow students.

Fun facts about life below water:

• 94% of Life exists in the Ocean
  More than half of the Earth is covered by water, and, therefore, a staggering majority of life exists within the oceans. It is expected that most people are surprised to learn that 94% of living species exist in the oceans.
  
  
• We now know almost a quarter of a million marine species
  Although the oceans are the most explored environments on the planet, we are still only aware of a small fraction of the species that exist in them. Based on the World Register of Marine Species, there are now 240,470 accepted marine species, but this is believed to only be a fraction of the species that exist, and as new creatures are being found every day, we are constantly gaining new insights into how life functions and what it means to be a creature in the ocean.
  
  
• Cuttlefish have 3 hearts
  Cuttlefish have not one, but three hearts! Two hearts are used to pump blood to the cuttlefish’s large gills, and the third heart is used to circulate oxygenated blood to the rest of the body.
  
  
• Only 5% of Ocean Has Been Explored
  Less than five percent of the Earth’s oceans have been explored. As researchers continue to search for more, we are learning more about the oceans with each passing day.
  
  
• Oceans Critical In Controling Green House Gases.
  Scientists suggest that the Oceans currently absorb 30-50% of the CO2 produced by the burning of fossil fuel. It’s believed that between 70 and 80 per cent of the oxygen we breathe is created by marine plants, nearly all of which are marine algae.
  
  
• The world’s longest chain of mountains is undersea.
  Earth’s longest chain of mountains, the Mid-Ocean Ridge, is almost entirely beneath the ocean, stretching across a distance of 65,000 kilometres. It’s stated that this chain of mountains is less explored than the planet surfaces of Venus or Mars.
  
  
• Coral Produce Their Own Sunscreen.
  Too much sunlight can damage the algae living inside coral at shallow depths. To protect the algae, a main source of nourishment for the coral, the corals fluoresce. This produces proteins that act as a sort of sunscreen for the algae.
  
  
• Fish can be very fast
  Swordfish and Marlin are the fastest fish in the ocean, reaching speeds up to 120 Km/h in quick bursts; Blue-fin Tuna may reach sustained speeds up to 90 km/h.
  
  
• Sound is much faster underwater
  Sound travels through water at approximately 1,435 meters per second – nearly five times faster than the speed of sound through air. This makes it nearly impossible for scuba divers to determine where a sound is coming from.
  
  
• Water travels well over 1000 years to circle the earth entirely.
  Water takes about a millennium to travel all the way around the entire globe. The oceans not only consist of waves, tides, and surface currents but also have a constantly-flowing system of ocean circulation driven by temperature and salinity. Known as the global ocean conveyor belt, it can take around a 1,000 years to complete this cycle.
  
  
• Tidal Movements can be up to 16m.
  The highest tides in the world is 16.3 m, over two-story building. This tide can be found at Bay of Fundy, which separates New Brunswick from Nova Scotia. At some times of the year the difference between high and low tide is a16.3 m.
  
  
• Success in scuba diving classes depend on smilling
  To save face out of the water, you must smile! This is so those around you know you're having a good time while they're stressed and fighting nausea.
  
  
• You can be intoxicated by just going under water
  Yup, that's right. Nitrogen narcosis, also known as ‘narks’ is a symptom that occurs to divers over 30 meters underwater. The increased pressure alters the state of the nitrogen and oxygen and breathing these gasses can make a person feel uncomfortably intoxicated. Talk about something to worry about on your next scuba dive.

You can learn more about these tidbits and more at Abyss Scuba Diving in Sydney NSW.