If there were no atmosphere, the average temperature on the surface of earth would be :-

Options

A. lower
B. higher
C. same
D. 0 C

Answer

To solve the question about the average temperature on the surface of Earth if there were no atmosphere, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Role of the Atmosphere**:
- The Earth's atmosphere plays a crucial role in regulating temperature. It traps heat through the greenhouse effect, which is caused by greenhouse gases like carbon dioxide and water vapor.

2. **Effect of Sunlight**:
- The Sun emits radiation, which reaches the Earth. Some of this radiation is absorbed by the Earth's surface, warming it.

3. **Heat Retention**:
- In the presence of an atmosphere, the heat that the Earth absorbs is partially trapped, preventing it from escaping back into space. This leads to a higher average temperature.

4. **Absence of Atmosphere**:
- If there were no atmosphere, there would be no medium to trap the heat. Consequently, the heat absorbed by the Earth would escape into space more readily.

5. **Conclusion on Average Temperature**:
- Without an atmosphere, the average temperature on the surface of Earth would be significantly lower than it is currently. Estimates suggest that the average temperature could drop to around -18 degrees Celsius (0 degrees Fahrenheit) or even lower.

6. **Final Answer**:
- Therefore, if there were no atmosphere, the average temperature on the surface of Earth would be much lower than the current average of approximately 15 degrees Celsius (59 degrees Fahrenheit).