What are greenhouse gases?
Greenhouse gases are gases in the Earth’s atmosphere that trap heat by absorbing and re-emitting infrared radiation and raise the surface temperature of the Earth. They include Water vapor(H2O), Carbon dioxide (CO2), Methane (CH4), Nitrous Oxide (N2O), Ozone and Fluorinated gases. These greenhouse gases are emitted in to the atmosphere through various Human activities, such as burning of fossil fuels, deforestation, agricultural activities, industrial processes, waste management etc. and by Natural processes.
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How do greenhouse gases cause global warming?
Greenhouse gases are infrared active, i.e. they absorb and emit infrared radiation in the same long wavelength range as what is emitted by the Earth’s surface. When sunlight reaches the Earth’s surface some of it is absorb by the land, oceans and other surfaces, then some of this absorbed energy back into the atmosphere as infrared radiation. A planet’s surface temperature depends on this balance between incoming and outgoing energy.
Greenhouse gases like Carbon Dioxide (CO2), Methane (CH4), Nitrous Oxide (N2O) in the atmosphere absorb and re-radiate this infrared radiation as thermal energy. This thermal energy warm the atmosphere above the Earth and trapping heat in the atmosphere. This trapped heat warms the Earth’s surface and lower atmosphere, leading to an increase in global temperature and this phenomenon is known as Global Warming.
Greenhouse gases have two different atoms, such as Carbon Dioxide(CO2), Methane (CH4), Nitrous Oxide (N2O); and all gases with three or more atoms are infrared active. Gases with only one atoms, such as Oxygen (O2), Nitrogen (N2) are transparent to longwave radiation and therefore do not absorb or emit longwave radiation, hence they are not infrared active.
Water vapor being responsible for 41-67% of the greenhouse effect, because in term of volume and its ability to absorb infrared radiation. Carbon Dioxide (CO2) is one of the primary greenhouse gases causing about three-quarters of global warming due to its ability to absorb and trap heat in the Earth’s atmosphere.
Methane (CH4) contributes to global warming and can react with other atmospheric compounds to produce Ozone (O3), which further enhances its warming potential. Its impact is around 25 times greater than that of Carbon Dioxide (CO2). Humane activities such as agricultural activities, industrial processes, combustion of fossil fuels release significant amount of Nitrous Oxide (N2O). Similar to Methane (CH4), Nitrous Oxide (N2O) absorbs infrared radiation and contribute to global warming.
Frequently Asked Questions:
What are the major greenhouse gases?
What are the main causes of global warming?
Is water vapor is a greenhouse gas?
Conclusion:
In conclusion, greenhouse gases play a critical role in global warming. Carbon Dioxide(CO2), Methane (CH4), Nitrous Oxide (N2O) and other greenhouse gases emitted from natural and human activities absorb infrared radiation, preventing it from escaping into space and leading to a gradual increase in global temperature. The consequences of this warming include rising sea levels, warming global temperature, changing precipitation, expansion of deserts, retreating glaciers, loss of sea ice in the poles etc.
