When blood enters the ocean, its red blood cells shrink and shrivel (crenation) due to the salty water drawing water out through osmosis; the blood rapidly disperses and loses its red color, appearing green or blue underwater as light absorption filters out red wavelengths, making it hard to detect by animals unless a large amount is present. Clotting is hindered by strong currents washing away factors, and the blood eventually breaks down, mixing with the saltwater environment.
Putrefaction and scavenging creatures will dismember the corpse in a week or two and the bones will sink to the seabed. There they may be slowly buried by marine silt or broken down further over months or years, depending on the acidity of the water.
Most of the ocean remains unexplored (around 80-95%) due to its immense size, extreme darkness, near-freezing temperatures, crushing pressure (over 1,000 times surface pressure in the deep), and the high cost and technological challenges of developing specialized equipment to withstand these harsh, hostile conditions. Sunlight can't penetrate far, visibility is near zero, and deep-sea life is adapted to pressure that would crush most vessels, making direct human study difficult and expensive.
The Science Behind the Color Change:
By the time you're about 30 feet underwater, most red light is gone, leaving mostly blue and green light. Blood appears red because it reflects red light. Without red light present, the blood reflects the green and blue light, making it look greenish or bluish.
However, the truth is that sharks don't go into a frenzy as soon as they smell blood. A few experiments conducted by brave individuals have proven this myth wrong. Feeding frenzies do occur; however, they are typically caused by too many sharks competing for too little prey.
We have a great deal more to learn about our ocean and what resides within it, but progress IS being made. We learn more and more each year. We continue to discover new features and creatures, clues to our past, and resources that can improve our future. But the ocean will never be fully explored.
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More than 70% of our planet is ocean – and 90% of that ocean is deep sea.
Summary: 2025 is a transformative year for ocean governance, marked by three landmark events: the UN BBNJ Convention entering into force, new WTO fisheries subsidies regulations taking effect, and the adoption of a historic political declaration at the 2025 UN Ocean Conference.
The wreck of the Titanic wasn't discovered until 1985, and in the years since, no trace of human remains has been found on or near it, most likely due to the sea's inhospitality to flesh and bones.
Scientists have found a hidden world deep beneath the Arctic Ocean that is changing how we understand life in the deep sea and how carbon moves through the Earth. This newly discovered ecosystem lies far below the ocean surface, in complete darkness and freezing cold, yet it is full of life, reported Newsweek.
Yes, human blood is green in the deep ocean. We have to be careful about what we mean by color.
Blood is 6 times thicker than water.
According to Revelation 16 verse 6 this is the retribution for the shedding of the blood of the holy people and the prophets. The changing of water into blood in Exodus 7 may be likewise retribution for the drowning of the new-born Hebrew boys in the Nile. In this first plague water is changed into blood.
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Ninety-five percent of the ocean remains unexplored not because it is empty… But because it is too powerful, too deep, too mysterious for us to rush into carelessly. The ocean is not hiding from us. We are slowly gathering the courage to meet it.
Geography. Lost City is located in the North Atlantic Ocean on the seafloor mountain Atlantis Massif, which is approximately the size of Mount Rainier. The site is described as a long-lived vent field, estimated to be older than 120,000 years by radiocarbon dating the oldest chimney deposits of the field.
Psalm 104:25-26 – “There is the sea, vast and spacious, teeming with creatures beyond number-living things both large and small. There the ships go to and fro, and Leviathan, which you formed to frolic there.” Psalm 95:5 – “The sea is his, for he made it, and his hands formed the dry land.”
The ocean floor covers more than 70 percent of the planet's surface. Like dry land, the ocean floor has various features including flat plains, sharp mountains, and rugged canyons (Fig. 7.1). However, the lowest point in the world ocean is much deeper than the highest point on land.
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It has traditionally been believed that sharks are repelled by the smell of a dead shark. However, modern research has had mixed results. Semiochemicals have shown some efficacy at getting sharks to leave a feeding area for a few minutes.
This constant movement means they don't sleep like humans do. However, when touched on the nose, a shark can enter a state called *tonic immobility*, a temporary sleep that lasts a few seconds. During this state, the shark may drop its lower jaw, resembling a yawn rather than aggression.
Tamayo Perry was fatally attacked by a shark on June 23, 2024, while surfing near Goat Island off Oahu's North Shore, sustaining multiple bites, including severe injuries to his arm and leg, after which fellow surfers brought him to shore, where he was pronounced dead by paramedics. He was on a break from his job as a lifeguard when the incident occurred, and officials later posted shark warnings in the area.