How water pressure affects the body

Some marine life can survive the extreme pressure of the deep ocean because of specialized molecules that strengthen proteins, enzymes, and cellular membranes.

NASA explores Earth's deepest oceans to prepare for space

By studying extreme environments in Earth's hadal zone—the deepest part of the ocean —NASA tests technologies, probes life under crushing pressure, and gathers clues about potential oceans and possible life on worlds like Europa and Enceladus.

View a gallery of animals found on abyssal plains, hydrothermal vents, seamounts, and other deep-sea habitats.

Explore the deepest parts of the ocean

The deeps of the Earth's oceans are some of the most extreme environments on the planet. Take a trip 36,000 feet to the deepest parts of the sea in this informative, 10-minute animated video.

How specialized oxygen mixtures like heliox enable deep diving without feeling drunk

Beyond a depth of about 30 meters (98 feet), if divers are breathing surface air, which is about 78% nitrogen, underwater pressure forces more nitrogen into the bloodstream and induces nitrogen narcosis, whose symptoms resemble alcohol intoxication. Through saturation diving, where nitrogen is replaced with helium—an inert gas—deep divers can maintain cognitive function while working for extended periods.

Although consuming saltwater can dehydrate and kill organisms, some fish survive by using specialized gills that leach excess salt from their bodies back into the surrounding water.

Explaining deep-sea mining, including its economic benefits and potential biomedical risks

Extraction via machines sweeping the ocean floor would reduce child labor and human rights violations currently occurring in land-based operations that collect the minerals needed for modern-day electronics. However, these sweeps may kill undiscovered organisms that possess biologies from which antibiotics could be derived and destabilize deep-sea ecosystems.

How the loss of Earth's atmosphere would cause oceans to boil at freezing temperatures

Many phenomena requiring air pressure, from the flight of birds and aircraft to the act of breathing, would no longer be possible. Because sound travels through vibrating air molecules, the loss of the planet's atmosphere would also create a silent environment. Even during daytime hours, the sky would resemble a clear night sky.

A look at hydrothermal vents, where barophiles and hyperthermophiles survive boiling water

Discovered in 1977 during an exploration of the Galapagos Rift, these seafloor openings spew hot magma and chemicals that heat seawater to hundreds of degrees. Without the sunlight found at depths of less than 1,000 meters (3,281 feet), extremophiles in these environments convert released chemicals into energy to survive, alongside surviving extreme pressures.

The warmest waters in the ocean are found at hydrothermal vents—hot springs on the seafloor that discharge plumes of mineral-rich water.

Blood pressure readings correspond to the peaks and valleys of heart beats

Pushing 2,000 gallons of blood through the body every day exerts a force known as blood pressure. Blood pressure is highest during the heart's contractile phase, known as systole, which forces blood through the circulatory system, and lowest during the heart's resting phase between beats, known as diastole.

An interactive of the deep sea

An overview of extremophiles and the biochemical adaptations employed by various types

These organisms thrive in environments that would normally be inhospitable to most living things by using molecules that help counter deadly environmental factors. These include antifreeze-like proteins that prevent psychrophiles from freezing and rupturing in polar regions, and osmoprotectants that prevent some extremophiles from losing water to salty environments.

Beyond a certain pressure and temperature, matter can become a supercritical fluid—an exotic state of matter that simultaneously exhibits properties of gases and liquids.

The boiling temperature of water decreases with increasing elevation because the molecules need less energy to overcome the lower atmospheric pressure associated with thinner air.

Quicksand—a mixture of sand with clay or silt soaked in water that gives way when enough pressure is applied—is denser than the human body, meaning you naturally float inside it.

The impact of gravitational force on our bodies surprised early coaster riders and engineers

There is only a certain amount of gravitational force that the body can handle before dealing with consequences like short-term vision loss or unconsciousness. Increased scientific understanding has largely reduced these impacts, with engineers combining periods of intense pressure with periods of relief.

The moon's gravity exerts an overall pressure that displaces the oceans toward the opposite sides of Earth's equator, producing tides.

Since the Industrial Revolution, surface ocean waters have become 30% more acidic due to the absorption of carbon dioxide.

Reduced inflammation from cold plunges lacks scientific support

The cold water triggers immediate cold shock, increasing heart rate and blood pressure, and prolonged exposure can lead to cold-water incapacitation and hypothermia. Plungers are encouraged to enter the water slowly and manage their breathing to reduce the risk of shock. Warm baths post-plunge are discouraged, and exercise is generally better for recovery.

Located in the Pacific Ocean, the Challenger Deep is the deepest point on Earth, extending to depths a mile deeper than Mount Everest is tall.

The deep-sea fangtooth has the largest teeth of any marine species relative to body size

From transparent fish to the heaviest worms on the planet, these seven creepy creatures lurk in the deep sea. Learn all about them and the unique traits that help them survive and hunt.

A chemical overview of water, whose uncommon properties help sustain life on Earth

The uneven distribution of charge in water molecules allows them to bond to each other and to surfaces, enabling them to move against gravity, including up plants through roots and stems. These bonds also keep water in a liquid state over a wider temperature range and make it less dense as it freezes. This causes ice to float and form an insulating layer for underwater ecosystems, from which all life originated.

Earth's oceans, which have an average depth of 3.7 kilometers (2.3 miles), may be divided into zones based on depth or the abundance of light.

The weight of Earth's atmosphere is equivalent to a 33-foot deep, global ocean

Because air is made up of gas molecules with mass, it is not weightless. On the planet's surface, we are effectively living in what is the equivalent of the bottom of an invisible ocean of these particles pressing against us, just as water molecules do when we are submerged.

Although an estimated 99.999% of the deep ocean has not been explored, techniques such as sonar have been used to identify the deepest known point in each of Earth's five oceans.

Cold water swimming can induce positive stress

The tradition of cold water swimming (or taking a cold plunge, or even a cold shower) has been shown to release the same hormones triggered during a stress response. This can have the effect of increasing blood flow, improved mental acuity, and more.

Can coral live in cold water?

Dive deep beyond the sunlit coral reefs, and you'll discover a world of deep-sea corals. This article from the National Oceanic and Atmospheric Administration (NOAA) explores the ecosystems of deep-sea corals found way below the water's surface....

How flooding the Dead Sea could help the climate

There are many dead zones in the world with low elevation and very little rainfall that provide little to no benefits to the ecosystem or climate. This digestible, thorough article explains how piping in nearby water to flood these areas could...

Starting with red, colorful objects will appear to lose their colors the deeper they are submerged because water scatters light, reducing the amount available to reflect off objects and be observed.

Watch a visualization of how Earth's oceans impact its atmosphere, weather, and climate.

A look at the concentrations of water in the human body and various organs

When we're born, about three-quarters of our bodies are composed of water, dropping to an average of 55-60% for the average adult. The lungs are over 80% water, the kidneys and spleen about 80%, and the heart and brain are approximately three-quarters composed of water—about the same moisture as a banana.

Deep-sea trenches form when one tectonic plate subducts another underwater

Oceanic plates sink when colliding with less dense continental plates, bending the seafloor into steep depressions that can be almost 11 kilometers deep. Many of Earth’s strongest earthquakes occur at these plate boundaries, often featuring volcanic activity.

Scientists define sea level as the elevation to which water would settle on Earth's surface, given the planet's gravitational field and rotation.

A visual exploration of the environmental impacts and uncertain demand for deep-sea mining

While models suggest demand for crucial metals is expected to exceed supply through 2050, new battery technologies, such as those that require no nickel or cobalt, introduce uncertainty that opponents of deep-sea mining see as not worth the risk of certain environmental damage, which includes noise and light pollution and the release of toxic plumes from mining equipment.

At 0.01 degrees Celsius (32.02 degrees Fahrenheit) and about 0.6% of Earth's surface pressure, water simultaneously exists as a solid, liquid, and a gas.

Read a technical review of extremophile categories, including the habitats of each

Acidophiles can survive in environments with acidity greater than that of the human stomach, and some radiophiles can live in places with radiation exposure hundreds of times higher than what is lethal to humans. Piezophiles—formerly known as barophiles—have been found in the Mariana Trench, where pressures are over 1,000 times larger than those on Earth's surface.

The ocean's ability to store carbon long-term is being hindered by marine heatwaves

More than 4,000 robotic floats with biogeochemical data sensors, including oxygen, pH, nitrate, suspended particles, chlorophyll, temperature, and conductivity, have been deployed as part of the Global Ocean Biogeochemical Array. They have identified changes to ecosystem structure affecting the ocean's ability to transport carbon from surface waters into the deep.

While major oil spills result from accidental pipeline ruptures or damage to transportation vessels or rigs, as much as half the oil that reaches coastlines has naturally leaked from the seafloor.

The ocean gets its salt from runoff carrying fragments of eroded rock and from seawater dissolving salts and minerals from magma at seafloor spreading centers.

Microplastics have been found across all of Earth's depths and altitudes, from plastic debris in the Mariana Trench to fragments found in snow samples near the summit of Mount Everest.

The 10 most amazing deep sea creatures

In this video, researchers from the world-renowned Monterey Bay Aquarium discuss the most fascinating deep sea creatures, and how they developed some of their strangest features.

How salt, sunlight, and wind drive ocean currents

The Atlantic Meridional Overturning Circulation plays a critical role in regulating earth's climate, but is threatened by climate change. Explore the effects of temperature, density, and salinity on ocean currents in this 13-minute PBS video.

How we know what's deep inside the Earth, despite never traveling there

We'll likely never see the Earth's core, but we can make educated guesses about what it's like down there. Nearly as hot as the sun's surface and under impossibly high pressure, the inner Earths extreme conditions make it impossible to explore. Yet, seismic waves during earthquakes, volcanic eruptions, and light waves from the sun provide fascinating insights about our planet's mantle, crust, and core.

Drugs in space: the pharmacy orbiting the Earth

Researchers are developing pharmaceutical solutions for astronauts, whose bodies may not respond the same way in space as they would on Earth. Similar to how microgravity causes changes to astronaut physiology, the environmental shift enables new...

The top several meters of the world's oceans can hold as much thermal energy as the entire atmosphere.

Santa Barbara divers helped innovate deepwater diving technology

Divers in the Santa Barbara channel innovated a more efficient type of diving helmet in the 1960s that used helium to allow for longer, deeper excursions for oil surveying, abalone collecting, and more. These innovators have since set the standard worldwide for military and industrial diving.

Certain medications that affect blood flow or mood boost the risk of heatstroke

Drugs that narrow blood vessels, beta blockers that regulate blood pressure, diuretics, antidepressants, and antipsychotics can all affect the body's ability to regulate its internal body temperature, and so individuals taking these medications need to take special care in extreme heat and when exercising in hot conditions.

If the temperature of water continuously decreases but it is not given room to expand, it will eventually contract and form exotic forms of ice that sink in liquid water.

38 thought-provoking facts about the ocean

Coral produces its own sunscreen, tsunamis move at 500 miles per hour, one of the loudest sounds ever recorded came from an ice quake, and other interesting facts collected from sources such as National Geographic and NASA.