Download notes distribution and transformation of solar energy

NOTES- 4/25 and 4/27
Distribution and transformation of solar energy on Earth
1. Describe the various pathways solar energy can follow as it reaches Earth.
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Reflected:
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Does NOT transform/change into heat energy
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Transforms into heat energy
by clouds= 20%
surface of earth= 4%
Atmosphere = 6%
Total = 30%
Absorbed:
by clouds and atmosphere= 19%
by the earth= 51%
Total = 70%
Plants
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Use light energy through photosynthesis and make oxygen and chemical energy
Plants, animals, humans use the chemical energy stored in food and through cellular respiration the chemical energy
is transformed into mechanical and heat energy
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Radiation: energy in waves through space or medium = electromagnetic radiation
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Sun = visible light, IR (heat), UV
Eventually all radiation is returned to space
2. What surfaces best convert light energy into heat?
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Dark surfaces: ocean, forests, asphalt
3. Describe the greenhouse effect and it's importance to Earth.
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Atmosphere (green house gasses within the atmosphere - CO2, H2O, methane) trap the heat
Natural
Keeps Earth warm - without the earth would be too cold for life