The correct Answer is 1 and 3 only
Explanation
The Earth's atmosphere is composed of several distinct layers, each characterized by specific temperature profiles, atmospheric composition, and physical phenomena. Understanding these layers and their properties is fundamental to atmospheric science.
Statement-wise Analysis
- Stratosphere : Contains the ozone layer
- Correct. The stratosphere is the second major layer of Earth's atmosphere, situated above the troposphere. It extends from about 10 km to 50 km above the Earth's surface. This layer is characterized by the presence of the ozone layer, which absorbs most of the Sun's ultraviolet (UV) radiation.
- Mesosphere : Temperature increases with altitude
- Incorrect. The mesosphere is the layer above the stratosphere, extending from about 50 km to 80 km. In the mesosphere, temperature generally decreases with increasing altitude, reaching its lowest point (mesopause) at the top of the layer.
- Ionosphere : Reflects radio waves back to earth
- Correct. The ionosphere is not a distinct layer but rather a region of the upper atmosphere (encompassing parts of the mesosphere, thermosphere, and exosphere) where solar radiation ionizes atoms and molecules, creating a layer of free electrons and ions. This ionized layer is crucial for radio communication as it reflects radio waves, particularly shortwave radio waves, back to Earth, enabling long-distance communication.
Key Takeaway
The stratosphere contains the ozone layer, and the ionosphere reflects radio waves, while the mesosphere experiences a decrease in temperature with increasing altitude.