Transcript Geothermal
What’s the Earth made of? Heat flows outward from Earth's interior. The crust insulates us from Earth's interior heat. The mantle is semi-molten, the outer core is liquid and the inner core is solid. Let’s look at an egg. What is Geothermal Energy? Did you know? • Animals have always known to burrow into the earth, where the temperature is stable compared to the air temperature to get shelter from winter’s cold and summer’s heat. • Today, with geothermal heat pumps, we take advantage of the stable temperature of the earth- about 45-58 degrees F. • These pumps go just a view feet below the Earth’s surface to help keep our indoor temperatures comfortable. Depending on the weather, the system is used for heating or cooling. • The pumps circulate water or other liquids through pipes buried in a loop next to a building. • Geothermal power plants run 24 hours a day, all year. These plants sit right on top of their fuel source and are resistant to interruptions due to weather, natural disasters, or transportation problems. • The United States alone produces 2700 megawatts of electricity from geothermal energy. That’s the same as burning sixty million barrels of oil each year. • When hot water and steam reach the surface, they can form fumaroles, hot springs, mud pots and other interesting phenomena. Too cool… • In Oregon, they pipe geothermal water under the roads and sidewalks to keep them from icing over in freezing weather- no snow days for them! • In New Mexico, they pipe geothermal water under soil where flowers and vegetables are growing. This keeps the ground from freezing, providing a longer growing season – more $$$$$ Let’s talk about the crust. • CRUST thin outermost layer of the Earth, solid rock which makes up the continents and the ocean floor. Mountains, hills, valleys, and plains look as if they have been in place forever. But all Earth’s landscapes are being worn away slowly. • Mountains crumble • Hills are worn flat • Valleys get wider What causes this? Erosion • Erosion is the process of breaking up rock and carrying off the fragments. • There are 3 types of erosion. • Can you guess them? Water Erosion • Water is a powerful agent of erosion. Rivers can carve out deep valleys, coastal waves beat the shore and create cliffs, and water can also split rocks apart. Wind Erosion • The power of the wind plays little part in shaping the land. But in dry landscapes, such as deserts, the wind can blast sand and dust at rocks and trees with devastating effect. Glacial Erosion • On some mountains it is so cold that snow never melts and over the years slowly compacts into a mass of ice. Eventually, this mass becomes so heavy that it starts to flow slowly downhill, forming a river of ice called a glacier. The glaciers are so strong they have the power to shape the land. What is a cycle? The seasons are a good example of a cycle. Now that you know what a cycle is what do you think a rock cycle is? Rocks can change into other rocks! The stuff that rocks are made from stays the same, but the rocks do not. Over time rocks are recycled into new rocks. Moving parts of Earth's surface layer help rocks recycle! This is the rock cycle. What do you notice about the cycle? Rocks are always on the move through the rock cycle. How does the rock cycle work? Like this!