Unit 2- Earth's Systems 1. The Atmosphere 2. The Lithosphere In this class, we will learn about 4 specific systems that make up the Earth. 1. The Atmosphere 2. The Lithosphere 3. The Hydrosphere 4. The Biosphere Now, there's a bunch more “spheres” that you can study in & around the Earth like the magnetosphere or ionosphere, but since this is only high school, we'll focus on these 4 basic ones. Image is from the following website: http://apod.nasa.gov/apod/ap980129.html 1

gases

The Atmosphere • The atmosphere is ALL THE GAS that is surrounding the Earth. This includes the air that you breathe. • Scientists split the atmosphere into different layers. • Extends 100's of kilometers above the planet. Images are from the following website: http://liftoff.msfc.nasa.gov/academy/space/atmosphere.html Atmo means “vapor”, so this is the sphere of (water) vapor. 3

The Atmosphere • Many different gasses are found in the Atmosphere. Check out this graph.... • Most abundant gas is... • Second most abundant is... • Others include Water Vapor Carbon Dioxide Argon Methane Images are from the following website: http://liftoff.msfc.nasa.gov/academy/space/atmosphere.html Atmo means “vapor”, so this is the sphere of (water) vapor. 4

The Lithosphere • Lithosphere is talking about the crust of the Earth and also the part of the Earth that is right under the crust that is called the Mantle. Image is from the website: http://ess.geology.ufl.edu/ess/Introduction/Geosphere.html 5

The Lithosphere • The land that makes up all the continents on earth is called CONTINENTAL CRUST. It is pretty thick, like 40-50 kilometers. • There is also crust on the floor of the ocean called OCEANIC CRUST. This is a bit skinnier, between 10-20 kilometers thick.

The Lithosphere • The Lithosphere is always in motion, but it is very gradual and usually takes hundreds to thousands of years to notice. The movement of the Earth's crust is known as PLATE TECTONICS. Image is from the website: http://ess.geology.ufl.edu/ess/Introduction/Geosphere.html 7

The Hydrosphere •Hydrosphere = ALL THE WATER on Earth, in all it’s forms (Gas, frozen, liquid) • 97% of Earth's water is in the Oceans. Most of the freshwater is frozen in glaciers & ice caps. Only a super tiny fraction of Earth's water makes up lakes + rivers. Image is from the website: http://water.tamu.edu/watercycle.html Hydro means “water”, so this is the sphere of water. 8

THE WATER CYCLE = water is always being THE WATER CYCLE = water is always being transferred from place to place

The Biosphere • “Bio” = living It includes ALL LIVING THINGS on Earth. All types of organisms are included: Archaea, Bacteria, Protists, Fungi, Plants, Animals. The places on Earth that are occupied by living things are called BIOMES. Image is from the following website: http://www.geology.ufl.edu/Biosphere.html Bio means “life”, so this is the sphere of life. 10

Modern humans? Only a few thousand... Remember: Earth's Systems are COMPLICATED and we still don't know everything about them. The Earth has been around for BILLIONS of years!!! Modern humans? Only a few thousand...

Earth's Systems Interconnected Earth systems are INTERCONNECTED – that means that they all have an effect on each other. The Earth system refers to the fact that we use models to look at parts of the Earth, helping us to describe what has happened in the past, what is currently happening, and what might happen in the future. 12