Pacific Ocean

Can you find the Pacific Ocean on a map? You should have no trouble. It covers more than one-third of Earth’s surface! That’s more area than all of the world’s land put together.

The Pacific is the world’s biggest and deepest body of water. In fact, it is about twice the size of the Atlantic Ocean, the world’s second largest ocean.

The World’s Oceans
Ocean	square miles	square kilometers
Pacific Ocean	63,980,000	165,700,000
Atlantic Ocean	31,810,000	82,400,000
Indian Ocean	28,360,000	73,440,000
Arctic Ocean	5,430,000	14,060,000

WHERE IS THE PACIFIC OCEAN?

The Pacific Ocean stretches west of the continents of North and South America all the way to Australia and Asia. At the western end of the Pacific are many islands. Some of them, such as the islands of Japan, the Philippines, Indonesia, and New Zealand, make up countries.

Geographers often divide the Pacific into two parts at the equator, the imaginary line that circles Earth at its middle. These parts are the North Pacific Ocean and the South Pacific Ocean.

HOW BIG IS THE PACIFIC OCEAN?

At its greatest width, from Panama in the east to Asia’s Malay Peninsula in the west, the Pacific extends about 11,000 miles (17,700 kilometers). North to south, from the Bering Sea to Antarctica, the Pacific measures 9,600 miles (15,500 kilometers).

LOTS OF ISLANDS

The Pacific Ocean has more than 30,000 islands. There are more islands in the Pacific than in all other oceans combined. The largest islands are in the western part of the Pacific. But many islands lie in the middle of the ocean. Most of these are small. The Hawaiian Islands are probably the biggest and best known of these.

WHAT’S THE OCEAN BOTTOM LIKE?

If you could drain the Pacific Ocean, you would find a rugged landscape. The Mariana Trench is located in the northwestern Pacific. It is the world’s deepest canyon. One part is 36,198 feet (11,033 meters) deep. There are also underwater mountain ranges. Some of the mountains rise above the surface to form islands.

Shallow, underwater plateaus, called continental shelves, extend along the coastlines of the continents bordering the Pacific. Off North and South America, the shelves are narrow. The shelves are wider along Australia and Asia.

RING OF FIRE

The Pacific Ocean sits on a huge slab of rock called the Pacific plate. This plate grinds and rubs against other plates surrounding it. The plate movements cause earthquakes and volcanoes in a zone that circles the whole Pacific Ocean. That’s why this zone is called the Ring of Fire.

Sometimes, underwater earthquakes or volcanic explosions cause great waves, called tsunamis. Tsunamis are often called tidal waves, but they have nothing to do with tides. They can cross the Pacific Ocean at speeds up to 500 miles per hour (800 kilometers per hour)! Tsunamis can cause terrible destruction when they reach land.

OCEAN CURRENTS

The waters of the Pacific flow in currents that form great circles. These currents are caused by constant winds and by the spinning motion of Earth itself.

The currents include a cold stream called the California Current. This current flows south along the United States. They also include the warm Japan Current that flows north along the Asian coast.

WHY IS IT CALLED THE PACIFIC OCEAN?

The name Pacific means “peaceful.” Is this ocean calm? Hardly. The Portuguese explorer Ferdinand Magellan named the ocean in 1520. He had just sailed around the tip of South America through violent storms. Magellan was grateful to find mild weather when he entered the ocean, so he named it Pacific.