Question

The greenhouse effect is caused by:
A) Greenhouse gases in the lower atmosphere absorbing solar radiation
B) Greenhouse gases in the lower atmosphere absorbing radiation from the Earth's surface, and preventing much of it from escaping into space
C) Too much heat in the atmosphere
D) Too much sunshine reaching Earth

Answer 1

Hint: Some gases tend to absorb solar radiation. There are about 1% of such gases that are present in our atmosphere which absorb the solar radiation fallen on earth and emitted back by the earth. Thus, it maintains the ideal temperature of the earth.

Complete solution:
The greenhouse effect describes the role our atmosphere plays in sustaining life on Earth. Energy from the sun in the form of Light passes through our atmosphere and warms the surface of the Earth which is then emitted back into the atmosphere in the form of infrared radiation. Greenhouse gases, which make up about one percent of the atmosphere, absorb and re-emitted heat, preventing much of it from leaving the Earth's atmosphere. This keeps our planet at a life-sustaining temperature to sustain life. There is a natural balance of these gases in the earth's atmosphere but due to human activities the amount of these gases are increasing in our atmosphere leading to more trapping of remitted energy leading to rising in temperature
Over time it is seen that our atmosphere has accumulated more greenhouse gases particularly carbon dioxide, methane, nitrous oxide, and fluorocarbons. This increased proportion of atmospheric gases traps more heat closer to the Earth's surface in the lower atmosphere and increases the average global temperature. This process called the 'enhanced greenhouse effect', is the reason for global warming.
Final Answer: (B), The greenhouse effect is caused by Greenhouse gases in the lower atmosphere absorbing radiation from the Earth's surface, and preventing much of it from escaping into space.

Note: The gases which are present in automobile emissions and the industrial chimney emission have a considerable amount of greenhouse gases which get accumulated into the lower atmosphere because due to their weight they cannot rise in the atmosphere. now as per their tendency, they absorb the energy emitted back by earth surface, as now their concentration in our atmosphere is increased the amount of energy they absorb will also be increased this leads to rising on average global temperature and this phenomenon is called global warming