The 'greenhouse effect' is when certain gaseous molecules (ie CO2 or H2O) absorb radiation at approximately the same wavelength as Earth's emission spectra (approximately centered on 15 micrometers; i.e. the infrared region). This serves to trap some of the energy which is emitted by the Earth. When this infrared radiation is reemitted, approximately half of it will return to the Earth's surface and be absorbed by the Earth.
In doing this, it changes the radiation (or energy) balance of the Earth.
Energy Balance over long periods:
Energy Absorbed by Earth = Energy Emitted by Earth
From the previous description it can be seen that the greenhouse effect, effectively increases the amount of energy which is absorbed by the Earth. This has the result of increasing the average temperature of the Earth's surface.
Theoretically, if the Earth had no atmosphere (and thus no greenhouse effect), the average temperature of the Earth's surface would be -18 C (using the Stefan-Boltzmann law). The actual average temperature is approximately 15 C, which proves that the greenhouse effect does actually exist!
the atmosphere plays the same roll as the walls of a green house. it keeps the warmth and the moister of the air inside the atmosphere so it wont escape. the air then just travels around the world and the winds bring the warm air to the polar regions to warm them up
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The 'greenhouse effect' is when certain gaseous molecules (ie CO2 or H2O) absorb radiation at approximately the same wavelength as Earth's emission spectra (approximately centered on 15 micrometers; i.e. the infrared region). This serves to trap some of the energy which is emitted by the Earth. When this infrared radiation is reemitted, approximately half of it will return to the Earth's surface and be absorbed by the Earth.
In doing this, it changes the radiation (or energy) balance of the Earth.
Energy Balance over long periods:
Energy Absorbed by Earth = Energy Emitted by Earth
From the previous description it can be seen that the greenhouse effect, effectively increases the amount of energy which is absorbed by the Earth. This has the result of increasing the average temperature of the Earth's surface.
Theoretically, if the Earth had no atmosphere (and thus no greenhouse effect), the average temperature of the Earth's surface would be -18 C (using the Stefan-Boltzmann law). The actual average temperature is approximately 15 C, which proves that the greenhouse effect does actually exist!
the atmosphere plays the same roll as the walls of a green house. it keeps the warmth and the moister of the air inside the atmosphere so it wont escape. the air then just travels around the world and the winds bring the warm air to the polar regions to warm them up