What is ozone hole ? What is its significance.

Explanation

### Step-by-Step Text Solution:

1. **Definition of Ozone Hole**:
The ozone hole refers to the depletion or thinning of the ozone layer in the Earth's stratosphere, particularly over the polar regions. This depletion results in a significant reduction of ozone concentration, creating a "hole" in the protective layer that shields the Earth from harmful ultraviolet (UV) radiation from the sun.

2. **Location of the Ozone Layer**:
The ozone layer is situated in the upper atmosphere, specifically in the stratosphere. It plays a crucial role in absorbing the majority of the sun's harmful UV rays.

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