Transcript Chapter 2
Chapter 2 World Geography: Looking at the Earth Section 1 • Planet Earth View of earth from space Chapter Earth Viewed From Outer Space • The Solar System – Made up of sun and all that revolves around it – Earth has an atmosphere • The air that surrounds the earth • Earth’s Measurements – About 93 million miles from the sun – Diameter of Earth at equator is about 8,00 miles Earth Viewed From Outer Space (Con’t) • Water, Land and Air – Earth is roughly 70% water • Oceans, Lakes, Rivers make up the Hydrosphere – Earth is roughly 30% land • Earth surface and crust is called the Lithosphere – All organisms live in the Biosphere Earth’s Surface • Inside the Earth – Composed of three layers • The Core – Inner and Outer core in the center of the Earth • The Mantle – Thick layer of melting material – Material from Volcano eruptions • The Crust – Thinnest of the three Only 3-30 miles deep – Planetlike rock that floats on the mantle Chart Supplement 1.2 Earth’s Surface (Con’t) • Internal Forces – Plates move only roughly 4 inches a year – When plates pull apart, melted rock rises up • Hawaii – Shaking or sudden movements in plates are earthquakes – When plates collide, the plates bend, fold, or crack (fault lines) – Underwater, when earthquake happens, tsunamis can occur • Tsunamis are large waves that can be as fast as 400 miles/hr. and up to 100 ft.tall – Pacific Plate • So active with earthquakes and volcanoes, it is called the Ring of Fire Map Supplement 1.1 Map Supplement 1.1 External Forces • Weathering – Breaking down of rocks – Two kinds: • Chemical weathering – Water dissolves chemicals in rocks, causing disintegration or break apart • Physical weathering – Breaks rocks into large pieces External Forces (Con’t) • Erosion – Wearing away of the earth’s surface by wind, water and glaciers – Wind • Movement of dust, sand and soil from one place to another – Plants help avoid wind erosion – Water • Water flows, which cuts the land, wearing away the soil and rock • Ex. – Grand Canyon External Forces (Con’t) • Erosion (Con’t) – Glaciers • Large bodies of ice, move across the surface of the earth • Similar to water flow erosion, however with even greater magnitude • Two types: – Glacier Sheet Large sheets… Greenland and Antarctica – Mountain Glacier Snow on mountain top turns to ice and begins moving down by gravity Section 2 • Earth’s Features Landforms • Continents – 7 Continents • Map of Continents • Isthmus – Connects two large landmasses – Isthmus of Panama connects North and South America • Europe and Asia separated by the Ural Mountains Landforms (Con’t) • Major Landforms – Mountains • Have steep slopes with some kind of peak or summit – Hills • More rounded and lower than mountains – Plateau • Higher than surrounding land and has one steep side, called a cliff – Plains • Flat or gently rolling lands Chart Supplement 2.1 Other Landforms • Valley – Lowland between to steep sides • Peninsula – Land surrounded by water on three sides • Island – Land completely surrounded by water • Archipelago – Closely scattered islands • Continental Shelf – Underwater extension of a continent Water Features • Oceans and Seas – 70% Earth is water and it is mainly salt water – Four major oceans • Pacific • Atlantic • Arctic • Indian – Seas, Gulfs, Bays • Smaller forms of salt water Water Features (Con’t) • Lakes, Streams and Rivers – Lake • Water completely surrounded by land • Most are freshwater – Stream • Body of water flowing, which combines to create rivers – River • A stream of considerable volume of water • Generally started by melting glacier, top of mountain or overflowing lake Water Features (Con’t) • Groundwater – Lies beneath earth’s surface and supplies wells and springs – Main source of groundwater is rain and melted ice • Water Cycle – Regular movement of water from ocean to air to ground to Ocean – Cycle Begins with Evaporation • Changing liquid water into vapor or gas Section 2-15 Section 3 • Earth’s Resources Importance of Resources • Natural Resources – Elements from the earth that are not made by humans but can be used by them • Minerals and Fuels – Minerals • Substances from earth that are not living or from living things – Fossils Fuels • Fuels derived from the remains of plants and animals that lived millions of years ago • Example – Coal, oil, gas Importance of Resources (Con’t) • Minerals and Fuels (Con’t) – Value of Resources • Determined by the purpose of the Resource • Supply, often influenced by location, also affects value – Oil debate today Managing Resources • Renewable Resources – Replace itself naturally or farmed to create a continuous supply • Vegetables, Sun/Wind power • Non-Renewable Resources – Can never be replaced – Many minerals and fossil fuels Distribution of Resources • Most resources are not evenly distributed • throughout the earth Trade – Import • Resources or goods brought into a country – Export • Resources or goods sent from one country to another • Uneven distribution of earth’s resources has led to an interdependence between countries – Also has led to many conflicts and wars www.nationmaster.com/lps/lesson_plan_Ene rgy.htm