Spheres of the Earth
- 10. A Look at Earth
- 17. Why do we need to know about Earth’s spheres?
- 18. Earth Systems Overview • The Earth is a system consisting of four major interacting components: • the atmosphere, • the biosphere, • the hydrosphere, and • the geosphere • Let’s examine each of these four spheres in detail………
- 19. The Atmosphere • The Earth is surrounded by a blanket of air, which we call the atmosphere. • The atmosphere consists of four unique layers (the troposphere, the stratosphere, the mesosphere, and the thermosphere). • The atmosphere reaches over 350 miles up from the surface of the Earth. • The atmosphere is primarily composed of nitrogen (about 78%) and oxygen (about 21%). Other components exist in small quantities.
- 20. What is the importance of the atmosphere? The atmosphere is an important part of what makes Earth livable. It blocks some of the Sun's dangerous rays from reaching Earth. It traps heat, making Earth a comfortable temperature. And the oxygen within our atmosphere is essential for life.
- 21. What destroys the atmosphere? Chlorofluorocarbons (CFCs) and other halogenated ozone depleting substances (ODS) are mainly responsible for man-made chemical ozone depletion. The total amount of effective halogens (chlorine and bromine) in the stratosphere can be calculated and are known as the equivalent effective stratospheric chlorine (EESC).
- 22. The Biosphere • The biosphere is the “life zone” of the Earth, and includes all living organisms (including humans), and all organic matter that has not yet decomposed. • The biosphere is structured into a hierarchy known as a food chain. • Energy and nutrients, like carbon, are transferred from one level of the food chain to the next.
- 23. What is the importance of the biosphere? The biosphere is as important as life itself because it is all of life. Without the biosphere, the Earth would be a lifeless planet such as Mars or Venus. ... Humans can have a huge impact on the biosphere, in both good and bad ways. The growth of the human population on Earth means there is less room for other species.
- 24. Hydrosphere • The hydrosphere contains all the water found on our planet. • Surface Water: Includes the ocean as well as water from lakes, rivers and creeks. • Ground Water: Includes water trapped in the soil and groundwater. • Atmosphere: water vapor. • Frozen water: Includes ice caps and glaciers. Also called the cryosphere. • Only about 3% of the water on Earth is “fresh” water, and about 70% of the fresh water is frozen in the form of glacial ice. (0.9% in liquid form)
- 25. Hydrosphere • The hydrosphere contains all the water found on our planet. • Surface Water: Includes the ocean as well as water from lakes, rivers and creeks. • Ground Water: Includes water trapped in the soil and groundwater. • Atmosphere: water vapor. • Frozen water: Includes ice caps and glaciers. Also called the cryosphere. • Only about 3% of the water on Earth is “fresh” water, and about 70% of the fresh water is frozen in the form of glacial ice. (0.9% in liquid form)
- 26. Geosphere The geosphere is the solid part of the earth, from the core to the surface. • Includes volcanoes, rocks, minerals, coal, oil etc. •Mineral resources are mined from the geosphere.
- 27. Earth System Science Earth System Science is the study of how the four spheres of the Earth system interact continually, each affecting the others. Example: A scientist that studies global warming is an Earth System Scientist.
- 28. System Interactions Volcanoes erupt, sending ash and gases into the air and sending lava and ash down onto surrounding forests and human habitations. Geosphere Atmosphere Biosphere
- 29. System Interactions Hurricanes sweep across the ocean and onto the land, damaging the dwellings of people who live along the coast. Atmosphere Hydrosphere Geosphere Biosphere
- 30. System Interactions Earthquakes can damage buildings which may kill people, as well as cause fires which release gases into the air. Earthquakes in the ocean may cause a tsunami which can eventually hit land and kill both animals and people. Geosphere Biosphere Atmosphere Hydrosphere