Global warming may result in :

Options

A. flood
B. cyclone
C. decrease in forest productivity
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding Global Warming:**
- Global warming refers to the gradual increase in the Earth's average temperature due to the accumulation of greenhouse gases, primarily from human activities such as burning fossil fuels and deforestation.

2. **Impact on Floods:**
- As the Earth's temperature rises, polar ice caps and glaciers begin to melt. This melting contributes to rising sea levels.
- Higher sea levels can lead to flooding in coastal areas, especially during storm surges or heavy rainfall events.

3. **Impact on Cyclones:**
- Global warming creates warmer ocean temperatures, which are conducive to the formation of tropical cyclones.
- Warmer air holds more moisture, leading to more intense storms and an increased frequency of cyclones.

4. **Impact on Forest Productivity:**
- The increase in temperature and changes in precipitation patterns can lead to disturbances in forest ecosystems.
- These disturbances may include increased frequency of storms, insect outbreaks, and wildfires, all of which can negatively affect forest health and productivity.

5. **Conclusion:**
- Given the impacts discussed, global warming can indeed result in floods, cyclones, and a decrease in forest productivity.
- Therefore, the correct answer is: **All of these.**

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