Greenhouse effect is the process where emissions of infrared radiation from other sources(e.g The Sun) or the atmosphere warms a planet's surface. It comes from the analogy of internal warming of a greenhouse as compared to external heat.
Basic mechanism:
Earth receives energy from the sun mainly through radiation as conduction and convection is not possible through the vacuum conditions of outer space. The Earth primarily reflects 30% of the incoming radiation through the clouds and land masses. The remaining of about 70% is absorbed to warm the land, atmosphere and oceans. In most cases, the infrared that are not absorbed by the surface are absorbed by greenhouse gases and clouds and thus unable to escape to space. For the earth to be at a constant state of temperature, the Earth does not gain or lose heat rapidly, thus the reflection and absorption should be rather constant through infrared radiation.
Cloud cover is generally one of the mechanisms for greenhouse effect because of it capability to trap and at the same time reflect infrared radiation. Clouds are generally white in color and as everyone knows, white objects are bad conductors but good radiators, they are therefore good reflectors and bad absorbers. Yet in the situation of greenhouse effect, they aid in reflecting and absorbing due to its nature. Incoming radiation are mostly reflected by cloud cover, and those that get in are kept in due to cloud cover, which explains why in some areas of the earth, there are major temperature ranges and in come near constant temperatures.
In deserts, in the day, due to lack of evaporation, cloud cover is low, and thus most of the radiation reaches the ground causing the temperature to rise rapidly. Yet at night, due to the lack of cloud cover, radiation escapes rapidly causing the rapid fall to extreme low temperatures at night.
Yet in the tropics, temperature ranges are not too extreme. High evaporation allows good cloud cover, as most of the heat are either reflected or absorbed, the temperature reaches a certain amount. And at night, cloud cover is still evident to regulated the heat within the area and thus does not promote the extremes of temperature ranges.
Greenhouse gases:
Common gases that causes greenhouse effects are H2O (36%), CO2 (12%), O3 (3%).
These gases though not the major gases in the atmosphere as compared to oxygen and nitrogen are good absorbers due to their quantum make-up.
These gases have a linear arrangement,
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