Earth as a System

Three Types of Systems Isolated Closed Open

Three Types of Systems 1. Isolated System Completely sealed off from its environment , neither matter nor energy passes through its boundaries. This is an imaginary construct, it is impossible to create a situation in which no energy is exchanged between the system and the environment. Earth is NOT an Isolated system. Under the right conditions it is perhaps conceivable that matter could be sealed out so completely that not even an atom could pass through a barrier, but some transfer of energy is inevitable. The reason is that electromagnetic energy, such as that emitted by the Sun, requires no material medium in which to travel.

Three Types of Systems 2. Closed System Energy can be exchanged with other systems, but not any actual matter. Maintains itself on a limited amount of resources that are enclosed in that particular system. On Earth, chemicals (matter) important to life move in cycles (Water, Carbon, Nitrogen, and Rock Cycles)

Three Types of Systems 3. Open System A material system in which mass or energy can be lost to or gained from the environment. Resources are renewed and exchanged on a regular basis. Energy is added and lost from the Earth. Energy from sun enters system (Earth) Heat energy flows out to space.

4 Spheres of the Earth

Atmosphere Mixture of Mostly Invisible Gases Extends outward 500-600km from Earth’s surface 90% of all gases are within the first 16 km of the atmosphere. Composition: 78% Nitrogen, 21% Oxygen, 1% other gases Allows life (O2 , CO2) Protects from UV (Ozone Layer = O3) CO2 regulates temperature

Lithosphere Physical Features, (mountains, rocks, beaches, ocean floor) 7-70 km thick Composition: Aluminum Potassium Calcium Iron Magnesium Silicates

Hydrosphere Oceans cover about 70-75% of surface. ½ of 1% is useable fresh water Formed from degassing and comet impact All water is recycled (closed system)

Biosphere Made up of all living things of the planet Ex. Protozoa, fish, plants, people, etc. Encompasses hydrosphere, lower atmosphere, upper lithosphere

How many parts of the Earth system can you identify in this image How many parts of the Earth system can you identify in this image? How do they interact?

How do Earth’s spheres interact? All of the spheres of Earth interact as matter and energy change and cycle through the Earth system. A result of these interactions is that they make life on Earth possible

Review What are the three types of systems? What are Earth’s spheres? How do satellites help us understand the Earth as a system? Biosphere 2 Scientists hope that incorporating global satellite data into their computer models will help them better understand the interactive roles of Earth's systems, and help them predict how the Earth's environment will change over time.

BIOSPHERE ATMOSPHERE GEOSPHERE HYDROSPHERE