Carbon dioxide (or CO2) is a gas generated mainly as a result of the combustion (burning) of organic matter. It is a greenhouse gas and causes global warming and hence is a cause of concern.
Greenhouse gases, like carbon dioxide, methane, etc., absorb some of the infrared emissions generated by the earth's surface when it becomes hot (due to heating by sunlight). The molecules of these greenhouse gases emit some of this heat back at Earth in the form of infrared emissions and this causes an increase in Earth's temperature. The rise in production of carbon dioxide due (chiefly) to the increased use of fossil fuels, higher crop production, higher population, etc. is a cause of global concern. The carbon dioxide levels in our atmosphere have been steadily increasing and have caused an increase in global average temperature. If continued unchecked, this rising carbon dioxide concentration will cause climate changes, shifts in crops, higher evaporation rates from surface water sources, the migration of plant & animal species, etc. Hence, global efforts are being carried out to cut down on the emissions of carbon dioxide.
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