- SOLAR ENERGY:
The Earth receives energy from the Sun all the time.
Some solar energy is absorbed as heat directly into rocks, soil, and bodies of water, raising their temperature.
Some solar energy is captured by plants in the process of Photosynthesis and is used to make biological (organic) compounds.
Many animals get their energy by eating plants; some animals eat other animals to obtain energy. Heat energy is lost at each step of this process.
Heat energy is also lost by animals and plants through respiration. The decomposition of deaqd bodies also releases heat.
- ALBEDO:
Some energy from the sun is reflected back into space.
The amount of reflection from a surface is called its albedo.
Water surfaces have a higher albedo than soil and rocks. Snow and ice have albedos even higher.
When glaciers melt and expose the soil and rocks under them, the albedo of the planet is reduced. More solar heat is captured by the rocks and soil.
When grass is paved over with asphalt to build roads and parking lots, the albedo of the planet is reduced. More solar heat is captured by dark, paved surfaces.
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