What is the phenomenon of gradual increase in global temperature called?

Options

A. Global cooling
B. Global warming
C. Ozone depletion
D. Atmosphere reduction

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the term used to describe the gradual increase in global temperature.

2. **Identifying the Term**: The correct term for this phenomenon is "Global Warming".

3. **Explanation of Global Warming**: Global warming refers to the long-term rise in the average temperature of the Earth's atmosphere and oceans. It is primarily caused by the increase in greenhouse gases, such as carbon dioxide (CO2), sulfur dioxide (SO2), and nitrogen dioxide (NO2), which trap heat from the sun.

4. **Mechanism of Global Warming**:
- The sun emits radiation that reaches the Earth.
- The Earth absorbs some of this radiation and then re-emits it as heat.
- Greenhouse gases in the atmosphere absorb this heat and re-radiate it back to the Earth, leading to an increase in temperature.

5. **Conclusion**: Therefore, the phenomenon of gradual increase in global temperature is called "Global Warming".

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