Earth: water

• Science
• 1st Grade

How do you use water in your daily life?

Where is water found on Earth?

Where does that water come from?

Water On Earth

Earth is called the blue planet. Do you know why?  

Are any other planets like Earth? What makes it so different? In this unit, we are going to be discovering all about Earth and what makes it so unique. Today, we are going to be investigating the blue part of Earth. We are going to be finding out about the forms of water.

70% of Earth is WATER!!!

What is water?

Water is a basic molecule that’s made up of two hydrogen atoms and one oxygen atom. When these three atoms come together, they form a super strong bond that is difficult to break. The strength of this bond keeps a water molecule together for millions and even billions of years. That’s incredible! Let’s explore some fascinating and perhaps shocking facts about water!

Water On Earth

Water is literally all over the Earth!  Around 70% of the Earth's surface is covered in water.  Around 97% of the Earth's water is in the oceans.  This is salt water and we can't drink it.  Less than 3% of the water on Earth is freshwater!  

Freshwater

2.4 % of the Earth's water is frozen water in glaciers and polar ice caps.  This leaves around 0.6  % of the water as freshwater in rivers and lakes that we can drink!

Freshwater

Rivers, creeks, lakes, ponds, and streams are all freshwater habitats. So are wetlands like swamps, which have woody plants and trees; and marshes, which have no trees but lots of grasses and reeds. Freshwater accounts for only three percent of the world’s water. (The rest is saltwater.)

Rivers 

Rivers are created when melting snow or ice runs down mountains, following the grooves and channels of the land on the way to the sea—rivers always flow to an ocean. Wetlands, areas where the land is covered with water most of the time, often form in the land surrounding rivers that flood, or in areas where groundwater seeps up through the bedrock underneath the soil. Bedrock is made of different types of rocks like granite, sandstone and limestone. Water can seep through the cracks between these rocks, and it can dissolve limestone. Beavers can even create wetlands by building dams on rivers and streams.

Lakes

Lakes are formed by different acts of nature. Many appeared after glaciers moved across Earth during the last ice age, between 12,000 and 1.8 million years ago, and left giant bowl-shaped hollows in the land that filled with rainwater and runoff. Others were created when Earth’s crust shifted, leaving grooves and ridges to catch water. And sometimes when a volcano erupts, all the magma flows out. If the land collapses into the empty crater, it leaves holes that can turn into huge lakes. Crater Lake in Oregon was made this way.

Glaciers

Glaciers begin to form when snow remains in the same area year-round, where enough snow builds up to transform into ice. Each year, new layers of snow bury and compress the previous layers. Each year, new layers of snow bury and compress the previous layers.

Polar Ice Caps

Polar ice caps are dome-shaped sheets of ice found near the North and South Poles. They form because high-latitude polar regions receive less heat from the Sun than other areas on Earth. As a result, average temperatures at the poles can be very cold. The polar ice caps contain the majority of Earth's supply of freshwater.

Freshwater Animals

Freshwater accounts for only three percent of the world’s water.  Despite that tiny amount, freshwater habitats are homes for more than 100,000 species of plants and animals.

More Than Just Fish

Fish living in freshwater habitats have plenty of company. Snails, worms, turtles, frogs, marsh birds, mollusks, alligators, beavers, otters, snakes, and many types of insects live there too. Some unusual animals, like the river dolphin and the diving bell spider, are freshwater creatures. Plants such as algae, cattails, water lilies, and aspen and willow trees help keep the water clean by using their root systems to filter pollution and excess nutrients from the water.

The Largest Freshwater Habitat

The largest freshwater habitat in the world is the Everglades, a 1.5 million acre wetlands in southern Florida. The Amazon River in South America begins in the Andes Mountains and goes 4,000 miles (6,400 km) to the Atlantic Ocean; it flows through six countries, including Peru and Ecuador. Lake Baikal in Siberia, a region in Russia, is the world’s biggest lake. This North Asian body of water contains one-fifth of all the freshwater on the planet.

So whether you’re a hungry turtle, a pollutant-sucking plant, or a thirsty human who also likes to play in the water, freshwater habitats are vital ecosystems for our planet!

Saltwater

From outer space Earth looks like an awesome blue marble. That’s because most of Earth’s surface—more than 70 percent—is covered by oceans.  Even though Earth has one continuous body of saltwater, scientists and geographers divide it into five different sections. From biggest to smallest, they are the Pacific, the Atlantic, the Indian, the Antarctic (sometimes called the Southern), and the Arctic Oceans.

How the Ocean Helps Earth

Oceans help keep Earth’s climate habitable. By moving water around the globe, the oceans help to keep places from getting too hot or too cold.

Water in the Atmosphere

Trees and other plants release water into the atmosphere—something called transpiration—then the water falls back to Earth as rain. Rain forest trees can release a lot of water, up to 200 gallons each year. The water forms a thick cloud-cover over the rain forest, so it is always warm and humid.

Ocean Animals

Scientists estimate that about one million species of animals live in the ocean. But most of them—95 percent—are invertebrates, animals that don’t have a backbone, such as jellyfish and shrimp. The most common vertebrate (an animal with a backbone) on Earth is the bristlemouth, a tiny ocean fish that glows in the dark and has needlelike fangs.

Ocean Animals

Some of the smallest animals on Earth can be found in the ocean. Sea animals like zooplankton are so small you can see them only with a microscope. Big fish swim through these waters too, such as great white sharks, manta rays, and ocean sunfish.

The largest animal ever to live on Earth is an ocean mammal called the blue whale. It’s as long as two school buses! Dolphins, porpoises, and sea lions are also ocean-dwelling mammals.

Ocean Plants

The ocean teems with plant life. Most are tiny algae called phytoplankton—and these microscopic plants have a big job. Through photosynthesis, they produce about half of the oxygen that humans and other land-dwelling creatures breathe. Bigger algae like seaweed and kelp also grow in the ocean and provide food and shelter for marine animals.

Ocean Tides

Tides are the rise and fall of the levels of the ocean. They are caused by the gravitational pull of the Sun and Moon as well as the rotation of the Earth.

Tsuanmis

Tsunami (soo-NAH-mee) is a Japanese word meaning harbor wave.

Tsunamis are NOT tidal waves!

Tidal waves are caused by the forces of the moon, sun, and planets upon the tides, as well as the wind as it moves over the water. 

TSUNAMIS

With typical waves, water flows in circles, but with a tsunami, water flows straight. This is why tsunamis cause so much damage!

Tsunamis are generated by any large, impulsive displacement of the sea level. The most common cause of a tsunami is sea floor uplift associated with an earthquake. Tsunamis are also triggered by landslides into or under the water surface, and can be generated by volcanic activity and meteorite impacts.

How often do tsunamis occur?

On the average, two tsunamis occur per year throughout the world which inflict damage near the source. Approximately every 15 years a destructive, ocean-wide tsunami occurs.

TSUNAMI CHALLENGE!

Simulate (create an artificial) TSUNAMI wave using water, a block, ruler, and a stopwatch.

Objective: To investigate and model the effect that water depth has on wave velocity.

Fill the water tank after your practice runs until you have 1 cm of water in the tank. Use the metric ruler for accuracy.

Have one team member ready with the stopwatch to start timing how long it takes a wave to travel from one end of the tank to the other.  

Place the block under one side of the container and when ready start stopwatch and pull the block away.  When the block is pulled away the wave is created! Make sure to stop the stopwatch when the wave hits the other end of the tank. Record the time in the data table.

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