Temperature gradient over earth surface is

Options

A. `6.4 "to" 6.5 ^@C` per 1000 m altitude
B. `6.4 "to" 6.5 ^@C` per 1000m latitude
C. `7.5 "to" 9.5 ^@C` per 1000m latitude
D. `7.5 "to" 9.5 ^@C` per 1000 m altitude

Answer

To solve the question regarding the temperature gradient over the Earth's surface, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Temperature Gradient**:
- The temperature gradient refers to the rate at which temperature changes with elevation or distance. It is typically expressed in degrees Celsius per unit of distance (e.g., per 1000 meters).

2. **Identify the Standard Temperature Gradient**:
- In the context of Earth's atmosphere, the standard lapse rate (temperature gradient) is approximately 6.4 to 6.5 degrees Celsius for every 1000 meters of elevation gain.

3. **Consider the Options Provided**:
- The question likely presents multiple-choice answers. We need to identify which option corresponds to the standard lapse rate of 6.4 to 6.5 degrees Celsius per 1000 meters.

4. **Select the Correct Option**:
- Based on the understanding that the temperature decreases by about 6.4 to 6.5 degrees Celsius for every 1000 meters of altitude, we can conclude that the correct answer is the option that states this gradient.

5. **Eliminate Incorrect Options**:
- Any options that do not reflect the standard lapse rate or provide different values should be disregarded as incorrect.

### Final Answer:
The correct option for the temperature gradient over the Earth's surface is **6.4 to 6.5 degrees Celsius per 1000 meters of altitude**.

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