3 - Earth's Subsystem

Atmosphere

Atmosphere

- gases (the air)

- the layers of gases around the Earth

- traps heat and shields Earth from harmful radiation

Troposphere

- weather occurs on this layer

- 0-12 km distance from the Earth

- the higher the altitude, the lower the temperature

Stratosphere

- where the ozone layer resides

- 12-50 km distance from the Earth

- higher altitudes, higher temperature

Mesosphere

- the coldest layer; it is also the middle layer, far enough from the sun and the Earth’s core

- 50-80 km distance from the Earth

- destroys and breaks down the meteors getting close to Earth

Meso

- means ‘middle’

Thermosphere

- 80-700 km distance from the Earth

- higher altitudes, higher temperature

- protects Earth from some of the sun’s most harmful radiation, x-rays, and some UV rays

Ionosphere

- from the word ‘ion’, it has highly charged particles causing lights

- auroras occur here

Aurora Borealis

- northern lights

Aurora Australis

- southern lights

Exosphere

- outermost layer

- 700-10,000 km distance from the Earth

- higher altitude, higher temperature

- is hit by solar flares and solar wind

- most satellites orbit here

Lithosphere

- solid earth

- the rigid outer shell of Earth

- consists of the crust and upper mantle

Oceanic Crust

- the ocean floors

- is thinner and denser than continental crust

Continental Crust

- forms large landmasses

- thicker than the oceanic crust

Sial

- silicone and aluminum

- the uppermost crust

Siam

- silicone and magnesium

- lowermost part of the crust

Mantle

- 84% of the Earth

- 2,900 km thick

Asthenosphere

- weakest layer of the Earth, found between the crust and upper mantle

- from the pressure, the solid becomes semi-liquid

Hydrosphere

- all water, no matter the state

Saltwater

- composes 97% of the Earth’s water

Freshwater

- composes 3% of the Earth’s water

Biosphere

- all life

- can be found in all three subsystems