Greenhouse Effect and Global Warming

· It is a natural phenomenon that keeps the earth’s atmosphere warm.

Ø Without this phenomenon, the temperature of the earth would become too cold for living beings to survive.

Ø The greenhouse gases (CO₂, methane, etc.) absorb the heat of sun and the earth and emit it back to the earth’s surface.

Ø Thus, these gases prevent a part of heat rays from escaping into atmosphere.

Ø This cycle is repeated many times to maintain the earth’s temperature to an optimum 15˚C.

Sunlight energy at the outermost atmosphere

· The concentration of these gases has increased due to increased industrialisation, leading to the heating up of the earth’s surface (global warming).

· This has increased the overall temperature of the earth, resulting in changes in the earth’s climate. During the last century, the temperature of earth has increased by 0.6˚C.

· This increase in temperature is ultimately believed to cause the melting of polar ice caps, rise in the sea level, and submerging of the coastal areas.

· Greenhouse effect can be controlled by reducing the use of fossil fuels, which produce greenhouse gases on burning, afforestation, efficient energy usage, etc.

Relative contribution of various greenhouse gases to total global warming