2.2 Land, Air, and Water Geography

2.2 Land, Air, and Water Vocabulary Landform Mountain Hill Plateau Plain Plate tectonics Ring of fire Pangaea Plate Weathering Erosion atmosphere

2.2 Land, Air, and Water Journal Entry Here’s your chance to be principal for a day. Write the speech you will make to your teachers outlining how they should behave while you are boss. Start with: –Today will be a good day for all of you who follow the new rules…

2.2 Land, Air, and Water What is the Earth Made of? –Continents are unique because of their landforms (shapes and types of land) –Mountains are landforms that rise usually more than 2,000 feet above sea level. They are wide at the bottom and rise steeply to a narrow peak or ridge. –Hills are lower and less steep than mountains, with rounded tops.

2.2 Land, Air, and Water –A plateau is a large, mostly flat area that rises above the surrounding land. At least one side of a plateau has a steep slope. –Plains are large areas of flat or gently rolling land. Many are along coasts. Others are in the interiors of some continents.

2.2 Land, Air, and Water Pangaea—The Supercontinent –For hundreds of years, as geographers studied the Earth’s landforms, they asked “where” and “why” questions. When they looked at the globe, they thought they saw a relationship between landforms that were very far apart. –Geographers theorize that millions of years ago the Earth had only one huge landmass. They called it Pangaea.

2.2 Land, Air, and Water Scientists reasoned that about 200 million years ago, some force made Pangaea split into several pieces, and it began to move apart. Over millions of years the pieces formed separate continents. (I would know everything in blue in order to answer an essay question or two on the test).

2.2 Land, Air, and Water A theory called plate tectonics says the outer skin of the Earth, called the crust, is broken into huge pieces called plates. The continents and oceans are the top of the crust. Below the plates is a layer of rock called magma, which is hot enough to be fairly soft. The plates float on the magma, altering the shape of the Earth’s surface.

2.2 Land, Air, and Water Volcanoes, Earthquakes, and shifting plates. –In some places, plates move apart, and magma leaks out through cracks in the crust. –In the oceans, over time, the cooling rock builds p to form lines of underwater mountains called ridges. –On either side of the line, the plates move away from each other.

2.2 Land, Air, and Water In other places, the plates push against one another, forcing one plate under the other. Tremendous pressure and heat builds up. Molten rock races upward, exploding onto the surface and producing a volcano. Weathering is a process that breaks rocks down into tiny pieces. Three things cause weathering: wind, rain, and ice.

2.2 Land, Air, and Water Air and Water: Two ingredients for Life –The Earth is surrounded by a thick layer of special gases called the atmosphere. It provides life-giving oxygen for people and animals and life-giving carbon dioxide for plants. –The atmosphere also acts like a blanket. It holds in the amount of heat from the sun that makes life possible

2.2 Land, Air, and Water About 97 percent of the Earth’s water is found in its oceans. This water is salty. Fresh water, or water without salt, makes up only a tiny percentage of all the Earth’s water. Most fresh water is frozen at the North and South poles. People need fresh water for many things. This fresh water comes from lakes, river, and rain.

2.2 Land, Air, and Water Much fresh water, called groundwater, is stored in the soil itself. Make sure that you have completed the vocabulary. Make sure that you have completed the journal entry.