Which of the following statements regarding the greenhouse effect has the lowest degree of certainty?

Options

A. Global warming will result in an increase in the number of tropical storms.
B. Addition of greenhouse gases to the atmosphere results in increased heat energy in the atmosphere.
C. Global warming will result in rising sea levels.
D. Full recovery from the enhanced greenhouse effect will require many centuries.

Answer

To determine which statement regarding the greenhouse effect has the lowest degree of certainty, we need to analyze each statement provided in the question. Here’s a step-by-step breakdown of the reasoning:

### Step 1: Understand the Statements
We have four statements to evaluate:
1. Global warming will result in an increase in the number of tropical storms.
2. Addition of greenhouse gases to the atmosphere results in increased heat energy in the atmosphere.
3. Global warming will result in rising sea levels.
4. Full recovery from the enhanced greenhouse effect will require many centuries.

### Step 2: Evaluate Each Statement
- **Statement 1**: Global warming will result in an increase in the number of tropical storms.
- This statement is based on projections and models, but there is still debate among scientists about the extent and certainty of this increase. Thus, it has a lower degree of certainty.

- **Statement 2**: Addition of greenhouse gases to the atmosphere results in increased heat energy in the atmosphere.
- This statement is well-supported by scientific evidence. The greenhouse effect is a well-established phenomenon.

- **Statement 3**: Global warming will result in rising sea levels.
- This statement is also supported by scientific data, as the melting of polar ice caps and thermal expansion of seawater due to warming are well-documented.

- **Statement 4**: Full recovery from the enhanced greenhouse effect will require many centuries.
- This statement is based on current understanding of climate processes and is generally accepted by scientists.

### Step 3: Identify the Statement with the Lowest Certainty
After evaluating the statements, it is clear that **Statement 1** has the lowest degree of certainty. While there is a possibility that global warming could lead to an increase in tropical storms, the evidence is not as strong or conclusive compared to the other statements.

### Conclusion
The statement regarding the greenhouse effect that has the lowest degree of certainty is:
**Global warming will result in an increase in the number of tropical storms.**

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