Interesting ocean facts for World Oceans Day

Here are some fun facts for students for World Oceans Day on 8 June 2010.

• The oceans moderate global climate, acting as the Earth’s climate control. They house the greatest number of living things.They are the Earth’s most prominent feature covering 362 million square kilometres, or nearly 71 per cent of the Earth’s surface. This is more than twice the area of Mars and nine times that of the Moon. More than 97 per cent of all our planet’s water is contained in the ocean and the top three metres holds as much heat as our entire atmosphere.
• The longest continuous mountain chain on Earth is in the ocean and is more than 55,000 kilometres long.
• The average ocean depth is 3720 metres. The deepest point of the ocean is 11,033 metres in Mariana Trench in the western Pacific Ocean. By comparison Mount Everest is 8848 metres above sea level. Its lowest point is in Challenger Deep, a small slot-shaped valley floor at the trench's southern end. Click here to see the trench. http://www.youtube.com/watch?v=5D3VkGkU5Dw
• Nearly one third of the world’s oil comes from offshore fields in our oceans. A large proportion comes from Western Australian waters. Millions of years ago, marine microscopic plants (phytoplankton) and animals (zooplankton) lived in the sea. When they died their skeletal remains settled to the sea floor, mixed with mud and silt and over millions of years formed organic rich sedimentary layers. Other layers covered them and as the depth of the burial increased, pressure increased, along with the temperature. Over long periods of time the original skeletal remains changed, breaking down into simpler substances called hydrocarbons – compounds of hydrogen and carbon which are now our oil supplies.
• If the salt in the ocean could be removed and spread evenly over the Earth’s land surface it would form a layer more than 166 metres thick, about the height of a 40-storey building.
• Atlantic sea water is heavier than Pacific sea water because its salt content is higher.
• Oceans contain nearly 20 million tonnes of gold.
• The blue whale is the largest animal on the planet – exceeding the size of the greatest dinosaurs. It s heart is the size of a Volkswagen car!
• Although coral reefs comprise less than 0.5 per cent of the ocean floor, it is estimated that more than 90 per cent of marine species are directly or indirectly dependent on them. This is thought to include about 4000 coral reef fish species worldwide, accounting for abut a quarter of all marine fish species. Tropical coral reefs border the shores of 109 countries and significant reef damage has occurred in 93 of these countries. Most of those countries are among the world’s least developed. Nearly 60 per cent of the world’s reefs – from tropical to temperate – are at significant risk of being lost in the next three decades. The Great Barrier Reef in Queensland is the largest living structure on Earth and can be seen from the Moon.
• Latest figures from Western Australia show 126 million barrels (20 gigalitres) of crude oil/condensate, and 30 billion cubic metres of gas, is produced annually. About 65 per cent of the gas is transformed into 12 million tonnes of LNG, all of which is exported by sea.
• An amazing 470 million tonnes of iron ore is exported from Western Australia each year, crossing the ocean in large iron ore carriers.
• Western Australia's overseas exports account for 36 per cent the nation's total. The state's major export commodities include iron-ore, alumina, crude oil and liquefied natural gas (LNG), nickel, gold, ammonia, wheat, wool, and live sheep and cattle. All are exported via shipping.
• Most of the world’s fisheries are being fished at levels above their maximum sustainable yield.
• Three quarters of the world’s largest cities are by the ocean or sea, and 80 per cent of all marine pollution comes from land-based activities. Plastic waste kills up to a million sea birds, 100,000 sea mammals and countless fish each year and remains in our ecosystem for many years, harming thousands of sea creatures every day.
• Less than half of one per cent of marine habitats are protected compared with 11.5 per cent of coastal land.
• Each year, illegal longline fishing, which involves lines up to 100 kilometres long, with thousands of baited hooks, kills more than 300,000 sea birds including 100,000 albatrosses.
• Oceans, seas and waters outside national jurisdiction are called the High Seas, where there are no protected areas for marine species.
• The total length of the world’s coastlines is enough to circle the Equator 12 times.
• The sea provides the biggest source of wild or domestic protein in the world. However, in one year, three times as much rubbish is dumped into the world’s oceans as the weight of fish caught.
• It is estimated that oceans contain as much as 50 quadrillion tonnes (50 million billion tonnes – 50,000,000,000,000,000) of dissolved solids. These include several salts including sodium, calcium, potassium and magnesium salts.

WAMSI would like to acknowledge that much of this information was sourced from the organisation, Saving the Sea.