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The surface of the Earth is covered by land and water.

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We have special names for different kinds of natural features, or landforms, on the Earth's surface.

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Come explore with me the Earth's landforms.

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The two largest types of landforms are continents and oceans.

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Continents are any one of the largest landmasses in the world.

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Traditionally, the Earth is divided into seven continents.

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From largest to smallest, they are Asia, Africa, North America, South America, Antarctica, Europe, and Australia.

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Oceans are large areas of saltwater between the continents.

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Although all of the oceans are connected to each other, making them one big ocean, we

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divide them into five smaller oceans that are separated by their location and the way

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the water in them moves.

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These oceans are the Arctic Ocean, the Atlantic Ocean, the Indian Ocean, the Pacific Ocean,

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and the Southern Ocean.

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are huge.

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Together, the oceans cover about 70% of the Earth.

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The Pacific Ocean is both the largest and the deepest ocean. It covers one-third of

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the Earth's surface. Smaller landforms are created in a variety of ways. Erosion from

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wind and water can wear down the Earth. Volcanoes and shifting tectonic plates can create new

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land or change the shape of old land.

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Let's take a look now at some of the different landforms and bodies of water that cover our

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planet.

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Mountains are some of the biggest and most recognizable landforms.

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They have steep sides and high peaks that stand out from the land around them.

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Smaller, less steep landforms are called hills.

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Mountains are usually formed when rock layers are pushed together from opposite sides, forcing

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the land up in the middle.

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The low areas between mountains are called valleys.

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Mountains may also be formed by volcanic activity, when lava and other materials build up on

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the surface.

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But mountains aren't the only landforms that can be made by volcanoes.

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When lava flows into the sea, it can create brand new land.

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Sometimes volcanoes in the ocean create islands.

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An island is a piece of ground that is completely surrounded by water.

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Islands can be big or small in any part of the world.

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The biggest island in the world is Greenland.

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Australia is bigger than Greenland, but it is so big that it is called a continent instead

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of an island.

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Two more landforms that involve a little land and a lot of water are peninsulas and isthmuses.

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An isthmus is a narrow strip of land with water on both sides, connecting two larger

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pieces of land.

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A famous example is the Isthmus of Panama that connects North America to South America.

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A peninsula is a piece of land that has water on three sides, but is connected on the fourth

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to the mainland.

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Two well-known peninsulas are Italy and Florida.

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Coastal areas have their own types of landforms. Bays, coral reefs, and lagoons are all landforms

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that may be found on or around the coasts.

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Another type of coastal landform is the estuary. An estuary is where a river meets the sea.

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There, the salt water from the ocean mixes with the river's fresh water, and the river

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spreads out, twisting and turning, wider and wider.

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Because of the way it spreads out, water in an estuary is generally shallow, which allows

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sunlight to penetrate all the way to the bottom.

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Rivers are important natural features themselves.

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They are fed by rain or melted snow.

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The water in rivers is called freshwater because it is not salty like water in the oceans.

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They begin in high ground, usually in hills or mountains, and follow gravity's pull

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down to lower ground.

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Smaller streams meet and join together, forming larger streams and rivers.

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These large rivers join together too, becoming larger and larger until they finally reach

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the ocean.

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Sometimes rivers will flow into large bodies of water before they reach the ocean.

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A large body of water surrounded by land is called a lake.

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A small body of water surrounded by land is called a pond.

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Not all lakes and ponds get their water from rivers.

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Some are filled only by rainfall.

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Most lakes are filled with fresh water, but some lakes are salty.

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One famous example of a salty lake is the Great Salt Lake in Utah.

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Another type of landform is a plain.

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Plains are large areas of flat land, with no hills or mountains in them.

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The Great Plains in the mid-United States is a good example of a large plain.

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The last landforms we're going to learn about today are plateaus.

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Plateaus are large areas of raised land that are flat on top.

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Plateaus may be caused by volcanic activity beneath the Earth's surface.

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Sometimes the pressure of the magma beneath isn't strong enough to break through the

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crust and create a volcano, so instead the land is pushed upwards.

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may stand all by themselves in otherwise flat land, or may sometimes be close to other plateaus.

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There are many more types of landforms that we didn't have time to discuss. Landforms

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are all around us.

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I hope you enjoyed learning about landforms with me. Goodbye till next time!