Earth Systems Overview

1. 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……… https://www.youtube.com/watch?v=BJgE7O0i0vk

2. 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 560 kilometers (348 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.

3. 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 the food chain (all life is dependant on the first tier – mainly the primary producers that are capable of photosynthesis). • Energy and mass is transferred from one level of the food chain to the next.

4. Hydrosphere The hydrosphere contains all the water found on our planet. • Water found on the surface of our planet includes the ocean as well as water from lakes and rivers, streams, and creeks. • Water found under the surface of our planet includes water trapped in the soil and groundwater. • Water found in our atmosphere includes water vapor. • Frozen water on our planet includes ice caps and glaciers. • 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.

5. Geosphere The geosphere is the solid Earth that includes the continental and ocean crust as well the various layers of Earth’s interior. • 94% of the Earth is composed of the elements oxygen, silicon, and magnesium. • The geopsphere is not static (unchanging), but its surface (crust) is in a constant state of motion. • Mineral resources are mined from the geosphere.

6. Earth System Science Earth System Science is the study of how the four spheres of the Earth system interact continually, each affecting the others. Let’s look at a couple of examples of how a change in one system (or sphere) affects other Earth systems.

7. System Interactions Volcanoes (geosphere) erupt, sending ash and gases into the air (atmosphere) and sending lava and ash down onto surrounding forests (biosphere) and human habitations (biosphere). Geosphere Atmosphere Biosphere

8. System Interactions Hurricanes (atmosphere) sweep across the ocean (hydrosphere) and onto the land (geosphere), damaging the dwellings of people (biosphere) who live along the coast. Hydrosphere Atmosphere Geosphere Biosphere

9. System Interactions Earthquakes (geosphere) can damage buildings which may kill people (biosphere), as well as cause fires which release gases into the air (atmosphere). Earthquakes in the ocean may cause a tsunami (hydrosphere) which can eventually hit land and kill both animals and people (biosphere). Biosphere Geosphere Atmosphere Hydrosphere

10. Earth’s Spheres Review https://www.youtube.com/watch?v=VMxjzWHbyFM

11. Constructive and Destructive Forces https://www.youtube.com/watch?v=fwFLc9ah5sE

12. Constructive ForcesIdentify surface features caused by destructive forces. • Construct means to build up. • Forces that build up features on the surface of the Earth. • Sediment (Deltas, sand dunes, etc.) • Volcanoes (makes Islands) • Tectonic Plates (Mountains) • Crust deformation (Folding or Faulting)

13. Sediment • The process of sediment being carried causes new landforms. • Wind – sand transported by the wind creates sand dunes. • Water – bits of soil and rock can be carried downstream and deposited causing deltas. • Ice – glaciers pick up and move rock and other materials, depositing it elsewhere.

14. Wind DepositionSand Dune Cumberland Island, GA

15. Water Deposition Sediment is carried by river

16. Glacial Deposition

17. Volcanoes • A volcano is an opening in the Earth's surface or crust, which allows hot, molten rock, ash and gases to escape from deep below the surface. • Volcanic activity involving the extrusion of rock tends to form mountains or features like mountains over a period of time. • Magma (inside) • Lava (outside)

18. Tectonic Plates • Mountains can be formed because of moving tectonic plates.

19. Destructive ForcesIdentify examples of surface features caused by destructive processes. • Destruct means to destroy. • Forces that destroy features on the Earth’s surface. • Erosion (water - rivers and oceans, wind) • Weathering (chemical or mechanical) • Impact of organisms • Earthquake

20. Earthquakes • An earthquake is a phenomenon that results from the sudden release of stored energy in the Earth’s crust. • It is caused by a strain on the fault lines of the Earth’s crust. When the energy of the strain is released, similar to a rubber band snapping, the earthquake occurs. • At the Earth's surface, earthquakes cause a shaking or displacement of the ground and sometimes cause the ground to break apart and change shape. Earthquake Animation!

21. Weathering and Erosion • Weathering is the breakdown of the continents and the land around you. The breaking down of these rocks and land due to forces such as wind and water is weathering. When it rains, rocks are washed down a mountain or down a stream. Soils are washed away. The ocean beats against a cliff and breaks it apart. If it is moved elsewhere it is called erosion. https://www.youtube.com/watch?v=R-Iak3Wvh9c

22. Mechanical Weathering • Mechanical weathering is the process of breaking big rocks into little ones. This process usually happens near the surface of the planet. Temperature also affects the land. The cool nights and hot days always cause things to expand and contract. That movement can cause rocks to crack and break apart. Roots and plants also push into the rocks and break them apart. They act like wedges and push the rocks apart. Little animals also help by burrowing and digging through the ground.

23. Chemical Weathering • Chemical weathering includes the effect of weathering on molecules and atoms. As with all chemistry, the greater the surface area of an object, the more chemical reactions can take place. For these chemical reactions to happen in nature, moisture, and heat must be present.

24. Earthquakes • More than buildings collapse when an earthquake hits. The land itself is totally changed. You can see scars across the landscape. Those scars appear when one block of land has moved compared to another. Roads often change their placement. They either become uneven or just crack. Streams can also change course. Sometimes rocks can fall and block the stream. Other times, the land is even lowered in certain areas. When it's lower, it's easier for the water to flow in the new direction .