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

Options

A. lower
B. higher
C. same as now
D. `0^(@)`

Answer

To solve the question of what the average temperature on the surface of the Earth would be 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 contains greenhouse gases that trap heat from the sun, preventing it from escaping back into space.

2. **Absence of the Atmosphere**:
- If there were no atmosphere, there would be no greenhouse gases or ozone layer. This means that the heat from the sun would not be trapped and would instead be lost to space.

3. **Effect on Temperature**:
- Without the atmosphere, the direct rays of the sun would still reach the Earth's surface during the day, but at night, there would be no atmosphere to retain any of that heat. As a result, the temperature would drop significantly during the night.

4. **Conclusion on Average Temperature**:
- The average temperature on the surface of the Earth would be much lower than it is currently. In fact, it is estimated that the average temperature could drop to around -18 degrees Celsius (0 degrees Fahrenheit) without the atmosphere.

5. **Final Answer**:
- Therefore, if there were no atmosphere, the average temperature on the surface of the Earth would be lower than it is now.