Question

Without____A___,the average temperature at surface of Earth would have been -18°C rather than the present average of ______.

• A. A: greenhouse effect, B: 15°C
• B. A: global warming, B: 10°C
• C. A: greenhouse gases, B: 20°C
• D. A: global warming, B: 5°C

Answer 1

The correct option is A A: greenhouse effect, B: 15°C

The greenhouse effect is a natural phenomenon that occurs when certain gases in Earth's atmosphere trap the sun's heat. These gases are called greenhouse gases (Carbon dioxide, methane, nitrous oxide and CFCs).

This phenomenon makes Earth much warmer than it would be without an atmosphere and makes Earth a comfortable place to live.

In the absence of the greenhouse effect the average temperature of the surface of Earth would have been a chilly -18°C. However, due to the greenhouse effect, the average temperature of Earth is 15°C.


The increase in concentration of greenhouse gases in the atmosphere leads to an increase in Earth’s average temperature. This is called global warming.