Carbon dioxide traps heat in the atmosphere. This is called the ______.

Answer

**Step-by-Step Solution:**

1. **Understanding the Role of Carbon Dioxide**: Carbon dioxide (CO2) is a gas that is present in the Earth's atmosphere. It plays a crucial role in regulating the Earth's temperature.

2. **Identifying the Layers of the Atmosphere**: The Earth's atmosphere consists of several layers. The first layer is called the troposphere, where most weather events occur. Above this is the stratosphere, which contains the ozone layer.

3. **The Process of Heat Absorption**: When sunlight reaches the Earth, it warms the surface. Carbon dioxide in the atmosphere absorbs some of this heat. This process helps to keep the Earth's surface warm.

4. **The Function of CO2**: The absorbed heat is then re-radiated back into the atmosphere, which helps maintain a stable temperature on Earth, especially during the night when temperatures tend to drop.

5. **Defining the Concept**: The overall process of CO2 trapping heat in the atmosphere and maintaining the Earth's temperature is known as the "Greenhouse Effect."

6. **Conclusion**: Therefore, the answer to the question is that carbon dioxide traps heat in the atmosphere, and this is called the **Greenhouse Effect**.

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