What makes the world's biggest waves?

The biggest ocean waves in the world, which regularly reach between 80 and 100 feet, are primarily caused by a 140-mile-long submarine canyon that reaches a maximum depth of 16,000 feet.

The Atlantic Ocean is home to the world's largest waterfall—the Denmark Strait cataract—which is more than three times the height of the largest land-based waterfall.

Although earthquakes cause about 80% of tsunamis, almost all earthquakes lack sufficient energy to cause the sudden shift in the ocean floor needed to substantially displace enormous volumes of water.

A tsunami—Japanese for 'harbor wave'—can begin with a drop in sea level before rising, which has contributed to its mistaken categorization as a tidal wave, despite being unrelated to the moon's gravity.

The world's largest species of marine algae is giant kelp, which can grow as much as two feet per day from depths of about 100 feet up to the ocean surface.

Lake Sørvágsvatn sits about 32 meters (105 feet) above sea level, but the taller surrounding cliffs create an optical illusion that makes it appear to float much higher above the ocean.

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.

Tsunamis are a series of waves rather than a single one, and boats are safer from them in deeper waters, where tsunami waves are smaller.

Whirlpool Rapids formed in a matter of days during the last ice age

Niagara Falls' dramatic whirlpool rapids were created in a matter of weeks when the retreating Falls intersected a buried ice age riverbed—generating North America's largest standing waves.

20 of the world's most iconic big rock wall climbs

Big wall climbs are tall rock faces that require climbers to "pitch" multiple times during the ascent—that is, reuse a rope. They also often portaledge, or sleep, at least once during the climb. Topping the list is California's El Capitan.

The tallest tsunami in recorded history was 524 meters (1,720 feet) high—taller than the Empire State Building—and occurred in Lituya Bay, Alaska, in 1958 after an earthquake dislodged a rockface into the water.

As of 2026, the Great Atlantic Sargassum Belt is the world's largest macroalgal bloom, with seaweed stretching from the Caribbean to West Africa.

Rather than being triggered by a massive displacement of water from a geological event, meteotsunamis are caused by rapid changes in air pressure from fast-moving weather systems.

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.

Deep Blue is the largest great white shark ever caught on camera

In 2019, Deep Blue was one of three huge great whites spotted off the coast of Oahu, Hawaii, an uncommon place for sightings of white sharks. The unique series of sightings aroused curiosity and amazement from islanders and scientists alike.

The massive sinkholes of China

Parts of China's limestone-rich terrain is fertile ground for massive caves, where some of the world's largest sinkholes are located. Hidden away in dense, lush forests, geologists are frequently discovering new sinkholes to explore. This piece...

Portugal's 1775 earthquake is considered Europe's first modern natural disaster.

The Southern Ocean features the Antarctic Circumpolar Current—the largest ocean current on Earth—which encircles Antarctica and creates a unique biogeographical zone.

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.

See an anamorphic illusion of a massive crashing wave in South Korea

An enormous aquarium with perpetually crashing waves has popped up amidst an urban landscape in South Korea, but don’t expect to hear the water sloshing around if you walk by. Designed by District, the elevated tank is actually a massive anamorphic illusion. The digital media company created the pub

What we know about the mysterious colossal squid

The colossal squid, the world's largest invertebrate, remained hidden from human discovery until nearly a century ago. Explore the world of the enormous and mysterious creature, including its features, habitat, and scientific significance. You can even plan a visit to the Museum of New Zealand Te Papa Tongarewa and marvel at a real-life display.

The world's largest garbage patch, explained

The Great Pacific Garbage Patch is the largest accumulation of ocean plastic in the world and is located between Hawaii and California. Scientists of The Ocean Cleanup Foundation have conducted the most extensive analysis ever of this area.

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.

The world's largest coral, as seen from space

The world’s largest individual coral colony—measuring over 100 feet wide and 100 feet long—was discovered in the Solomon Islands. This coral is so large it can be seen from space, and is estimated to be between 300 and 500 years old. The coral's size and health provide hope amidst a global coral bleaching crisis, wherein three-quarters of coral reefs have experienced significant bleaching in recent decades. See the photos from space and learn more here.

As of 2025, wave power projects remain in early research and testing phases

Waves can become a steady source of renewable energy because they do not pause like wind and solar power do. However, funding gaps and the effects of storms, salt exposure, and biofouling—mussels and other sea creatures attaching to wave machines—have presented challenges in scaling the technology beyond testing sites.

The largest river on Earth is actually in the sky

High above the canopy of the Amazon rainforest drifts an airborne river fed by the towering trees below. The trees pull water from their roots into their trunks, pushing any excess water out of their leaves and into the atmosphere as vapor. Watch this six-minute video to learn how.

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.

The world's largest deserts—areas that receive less than 10 inches of annual rainfall—are led by the Antarctic and Arctic regions.

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.

Various types of tornadoes are distinguished by their shape, size, and location

Waterspouts form over water as long, thin columns of mist and air, while elephant trunks are tornadoes that elongate vertically as they become tilted during their formation, resembling the mammal's appendage. Wedge tornadoes are among the most powerful, often spanning a mile or more in width.

Reaching 2,400 kilometers per hour (1,500 miles per hour), Neptune's winds are the strongest in the solar system.

Due to their enormous size, wind turbines are assembled on-site using prefabricated components, advanced cranes, and vibration-damping systems to withstand the dynamic ocean environment.

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.

This Town Advertised the World’s Largest Well. It Wasn’t.

How the soccer World Cup works

The World Cup is the biggest game in the world. Watch this video to learn how it works and how it came to be such a massive world event.

Satellite imagery of the massive seaweed blob in the Atlantic

A belt of sargassum seaweed that stretches from the west coast of Africa to the Gulf of Mexico is the largest on record for March.

The Valley of Mexico sits over 7,000 feet above sea level

Once dominated by the shallow waters of Lake Texcoco, the high-altitude Valley of Mexico—surrounded by volcanic peaks—was home to the Aztec capital Tenochtitlan. This resource breaks down the region’s unique geography and why it became a cradle of Mesoamerican civilization.

How the moon creates tides

Anyone who has visited large bodies of water virtually anywhere on Earth notices low and high tides occur at regular intervals, a process primarily driven by the moon’s gravitational pull. This explainer details how the motion of the Earth and Moon interact to create tides.

Hurricane conditions are created in a University of Miami wind-wave tank

The SUrge-STructure-Atmosphere INteraction Wind Wave Laboratory contains a 38,000-gallon wave pool connected to a wind tunnel that can generate air currents of up to 155 mph. SUSTAIN allows scientists to study how the atmosphere interacts with the ocean in extreme weather.

Why is sea level rising?

Rising global sea level is one of the most commonly cited consequences of climate change, but it’s often unclear how it might affect people living on the coasts. Read this explanation of why global sea level is rising and why sea level rise happens at different rates in different locations.

Infrastructure built to limit tsunami damage includes channels to divert water, floodgates, and seawalls, such as the approximately 400-kilometer (249-mile) wall built in Japan after the 2011 Tōhoku earthquake and tsunami.

Most volcanic activity occurs in submarine volcanoes on the seafloor

At divergent plate boundaries in mid-ocean ridges, volcanic activity produces new ocean crust as the seafloor spreads. These areas are home to underwater mountains with extensive biodiversity due to redirecting ocean currents and concentrating food for marine life.

Wave tanks can be used to create and study the impacts of tsunamis by building tension in an underwater object before allowing it to slip and rapidly displace water.

Dust from the Sahel and Saharan regions makes northwest Africa a hurricane nursery

NASA’s Convective Processes Experiment—Cabo Verde studied the early stages of hurricane formation, identifying how dust interacts with clouds over the ocean to produce the rainy disturbances that become tropical cyclones.

Ranking the 10 hottest places on Earth

Death Valley in California often gets the press for the hottest recorded air temperature in the world. What about the runners-up? This list compiles the rest of the Earth's hottest spots, from Jeddah in Saudi Arabia to Kebili in Tunisia.

Storm surges, not winds, are the leading cause of hurricane-related fatalities

A storm surge is an abnormal rise in water levels generated by a storm that exceeds predicted tides. It is particularly dangerous in coastal regions, where it can generate extreme flooding well before the hurricane makes landfall.

Because seismic waves travel 100 times faster than tsunami waves—waves typically travel faster through solids than liquids—measurements of geological activity help tsunami detection systems provide early warnings.

Watch a visualization of global ocean currents from NASA's Estimating the Circulation and Climate of the Ocean project.

Often considered the largest natural mirror on Earth, Bolivia's Salar de Uyuni is the world's largest salt flat—a desert formation covered in minerals.

Visualizing the 75 largest underwater animals

With so many fish in the sea, which are the largest? This infographic shows fantastic illustrations of the 75 largest sea animals, ranked by average size. The detailed visual is organized in descending order of size, starting with the blue whale,...