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The Greenhouse Effect
A greenhouse gas is a gas in an atmosphere that absorbs and emits radiation within the thermal
infrared range. This process is the fundamental cause of the greenhouse effect.
Greenhouse effect is often confused with global warming. It is believed that greenhouse effect causes
global warming however, the truth couldn't be far from this.
What is the greenhouse effect?
The greenhouse effect warms the Earth naturally. To warm the Earth, it relies on the Sun's energy.
When the Sun's energy reaches the Earth's surface, around 49% of it is absorbed and the rest is
reflected back to space. This absorbed energy warms the Earth's surface, which in turn radiates heat
energy back towards the space. While this warm energy is travelling towards space, it is partially
trapped by greenhouse gases. The trapped energy is then released in all directions, warming the earth's
surface and atmosphere. This process of warming the Earth is known as the greenhouse effect.
The greenhouse effect is a process by which thermal radiation from a planetary surface is absorbed by
atmospheric greenhouse gases, and is reradiated in all directions. Since part of this reradiation is back
towards the surface, energy is transferred to the surface and the lower atmosphere. As a result, the
temperature there is higher than it would be if direct heating by solar radiation were the only warming
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Many of the greenhouse gases are naturally occurring, which is the cause of natural global
warming. Without naturally occurring greenhouse gases, the earth's
surface temperature would average 33 degrees Celsius cooler.
Over the past 250 years, carbon dioxide levels have increased by 25%.
In the past 15 to 20 years, there has been an overall rise in temperatures.
The first person to predict the greenhouse effect was a Swedish chemist
named Svante Arrhenius.…read more