Without green house effect, the average temperature of earth's surface would have been

Options

A. `-18^(@)C`
B. `33^(@)C`
C. `0^(@)C`
D. `15^(@)C`

Answer

To solve the question regarding the average temperature of the Earth's surface without the greenhouse effect, we can follow these steps:

### Step 1: Understand the Greenhouse Effect
The greenhouse effect is a natural process where certain gases in the Earth's atmosphere trap heat. This process keeps the Earth's surface warmer than it would be without these gases.

### Step 2: Consider the Role of Solar Radiation
Solar radiation from the sun reaches the Earth in the form of short-wave energy. This energy is absorbed by the Earth's surface, which then re-emits it as long-wave infrared radiation.

### Step 3: Analyze the Impact of the Absence of Greenhouse Gases
Without greenhouse gases, the heat that is radiated back into space would not be trapped. As a result, the Earth's surface would lose a significant amount of heat, especially during the night.

### Step 4: Determine the Average Temperature
According to the information provided, without the greenhouse effect, the average temperature of the Earth's surface would drop significantly. It is stated that the average temperature would be approximately -18 degrees Celsius, which is similar to the average temperature on the moon, where there is no atmosphere to retain heat.

### Step 5: Conclusion
Thus, the average temperature of the Earth's surface without the greenhouse effect would be -18 degrees Celsius.

### Final Answer
The average temperature of Earth's surface without the greenhouse effect would be **-18 degrees Celsius**.

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