Interesting And Increduble Facts about Seas and Oceans

Life originated in the seas between 3.1 billion to 3.4 billion years ago. Terrestrial life appeared around 400 million years ago, which is relatively recent in geological time.

It is estimated that 50-80% of all life on Earth resides beneath the ocean’s surface, with oceans accounting for 99% of the planet’s living space. Less than 10% of this space has been explored by humans. Of this, 85% of the area and 90% of the volume are represented by the dark, cold environment we call the deep sea. The average depth of the ocean is 3,795 meters, while the average land elevation is 840 meters.

Currently, scientists have named and successfully classified over 1.5 million species of living organisms. It is estimated that 2 to 50 million species remain undiscovered and/or incorrectly classified.

According to the World Register of Marine Species (WoRMS), there are currently 199,146 named marine species. There are likely at least 750,000 marine species (50% of the 1.5 million existing species) and possibly up to 25 million marine species (50% of the 25 million).

Interesting Facts About Seas and Oceans

1. The swordfish and marlin are the fastest fish in the ocean, reaching speeds up to 121 km/h in bursts. The bluefin tuna can maintain speeds up to 90 km/h.
2. The blue whale is the largest animal ever to have lived on our planet, surpassing even the largest known dinosaurs, with a heart the size of a small car.
3. The oarfish, with a snake-like body and a stunning red fin running the length of its body, can reach up to 15.25 meters in length.
4. Many fish can change sex during their lifetimes. Some, especially rare deep-sea fish, possess both male and female reproductive organs.
5. Deep-sea exploration has revealed 898 species from more than 100 families and a dozen phyla in an area roughly the size of half a tennis court, with over half of these organisms being new to science.
6. A new form of life based on chemical energy rather than light energy exists in deep-sea hydrothermal vents along mid-ocean ridge systems.
7. A mouthful of seawater contains millions of bacterial cells, hundreds of thousands of phytoplankton, and tens of thousands of zooplankton.
8. The gray whale travels more than 10,000 miles annually, making it the longest migration of any animal.

Ocean Geology

The ocean covers 71% of the Earth’s surface and contains 97% of the world’s water. Less than 1% is fresh water, and 2-3% is locked in ice caps and glaciers.

• 90% of Earth’s volcanic activity occurs in the oceans.
• The speed of sound in water is 1,435 meters per second, almost five times faster than in air.
• The highest tides in the world occur in the Bay of Fundy, Canada, with differences between high and low tide reaching up to 16.3 meters, taller than a three-story building.

Notable Features

• The Mid-Ocean Ridge is the longest mountain range on Earth, stretching over 50,000 km, encircling the globe from the Arctic Ocean to the Atlantic, around Africa, Asia, Australia, through the Pacific to the west coast of North America. It is four times longer than the Andes, Rockies, and Himalayas combined.
• The pressure at the ocean’s deepest point is over 11,318 tons per square meter, equivalent to a human trying to lift 50 airplanes.
• The Challenger Deep in the Mariana Trench is the Earth’s lowest point, 11,034 meters deep in the western Pacific Ocean. If Mount Everest were placed at the trench’s bottom, there would still be a mile of water above it.
• Underwater earthquakes, volcanoes, and landslides cause tsunamis, with the highest recorded tsunami wave reaching 60 meters above sea level in Alaska’s Lituya Bay in 1899.

Atlantic and Pacific Oceans

• The average depth of the Atlantic Ocean and adjacent seas is 3,332 meters, or 3,926 meters without them. The deepest point is the Puerto Rico Trench at 8,381 meters.
• The Pacific Ocean, the largest water body, covers a third of the Earth’s surface, containing about 25,000 islands, mostly south of the equator, and spans an area of 179.7 million square kilometers.
• The Kuroshio Current near Japan is the strongest current, moving at 40-121 kilometers per day and reaching depths of 1,006 meters. The Gulf Stream in the Atlantic moves similarly fast and carries 100 times more water than all the world’s rivers combined.

Sea Level and Ecology

• The sea level has risen at an average rate of 10-25 cm over the past 100 years, and scientists expect this rate to increase.
• The world’s oceans contain nearly 20 million tons of gold.
• The blue color is the least absorbed by seawater and is most absorbed by microscopic plants, phytoplankton, floating in the water.

Temperature

• Seawater becomes denser as it cools, freezing at -1.9°C, while freshwater is densest at 4°C and freezes at 0°C. The average ocean water temperature is 3.5°C.
• The upper 10 feet of ocean water contain as much heat as the entire atmosphere.
• Deep ocean water can reach high temperatures without boiling due to incredible pressure. Temperatures of 400°C have been recorded in hydrothermal vents.

Ice

• Almost all deep ocean water is only slightly above freezing.
• Ice covers 10% of the Earth’s surface.
• Antarctica holds as much ice as the water in the Atlantic Ocean.
• The Arctic produces 10,000 to 50,000 icebergs yearly, and estimating those produced around Antarctica is impossible. Icebergs typically last four years, entering shipping lanes after three years.

Pollution

• Air pollution causes 33% of all toxic waste in oceans and coastal waters, and 44% of all pollution comes from rivers and streams.
• Each year, three times more garbage is dumped into the ocean by weight than fish are caught.
• Oil, one of the world’s richest resources, is extracted from offshore sites, with popular drilling locations including the Arabian Gulf, the North Sea, and the Gulf of Mexico.

Coral Reefs

• The Great Barrier Reef is the world’s largest living structure, visible from space, comprising 400 coral species, 2,000 fish species, 4,000 mollusk species, and countless other invertebrates. Other large reefs include the New Caledonian Barrier Reef, the Mesoamerican (Belize) Barrier Reef, and the Great Barrier Reef of Fiji.
• Coral is similar in architecture and chemistry to human bones and is used as bone grafts to help bones heal quickly and cleanly.
• Tropical coral reefs fringe the coasts of 109 countries, most of which are among the least developed. Significant reef decline has been observed in 93 countries.
• Coral reefs cover less than 0.5% of the ocean floor but are estimated to support over 90% of marine species directly or indirectly.
• There are about 4,000 coral fish species worldwide, accounting for roughly 25% of all marine fish species.
• Nearly 60% of all coral reefs are at risk of disappearing within the next 30 years.
• The main reasons for reef decline include coastal development, sedimentation, destructive fishing practices, pollution, tourism, and global warming.

Human Interaction with Oceans

• Three-quarters of the world’s largest cities are located on coastlines.
• 80% of the Earth’s population lives within 60 miles of the coast.
• The high seas, areas of the ocean outside national jurisdiction, account for nearly 50% of the Earth’s surface and are the least protected part of the world.
• Although there are agreements protecting ocean inhabitants like whales and fishery agreements, there are no agreements to protect the high seas.
• Nearly 3.5 billion people rely on oceans as their primary food source. This number could increase to 7 billion in 20 years.
• Fish provide the highest percentage of the world’s protein consumed by humans, and many fish species are overfished beyond sustainable levels.
• The record for the deepest dive belongs to Jacques Mayol, who dived to an astonishing depth of 105 meters without any equipment.
• Over 90% of international trade is carried out by ships, and over half of inter-country communication is done through underwater cables.

Sharks

• Sharks attack about 50-75 people worldwide annually, with 8-12 fatalities, according to the International Shark Attack File (ISAF). Despite the attention shark attacks receive, they are much less frequent than deaths caused by elephants, bees, crocodiles, lightning, and many other natural hazards. Conversely, humans kill approximately 20-100 million sharks annually due to fishing.
• Of the 350 shark species, about 80% grow to less than 1.6 meters and are not harmful to humans, rarely encountering them. Only 32 species have been recorded attacking humans, and another 36 are considered potentially dangerous.
• Nearly any shark 1.8 meters or longer is potentially dangerous, but three species are most likely to attack humans: the great white shark, tiger shark, and bull shark. All three are found worldwide, reach large sizes, and prey on large animals like marine mammals and sea turtles.

Great white sharks are more likely to attack swimmers, divers, surfers, and boats than any other species. However, about 80% of shark attacks occur in the tropics and subtropics, where other shark species are more common, and great whites are relatively rare