We live in troposphere.we breathe air.as a result the air we breathe exists in troposphere

Troposphere
The troposphere is the lowest layer of the Earth's atmosphere, extending from the surface up to an average height of about 7-20 kilometers (4-12 miles). This layer is where weather occurs and where we live and breathe. It is characterized by a decrease in temperature with increasing altitude.

Explanation:
The air we breathe primarily exists in the troposphere. This layer contains the highest concentration of atmospheric gases, including nitrogen (78%) and oxygen (21%). Other trace gases such as carbon dioxide, water vapor, and various pollutants are also present in this layer.

Importance of the Troposphere:
1. Oxygen for respiration: The troposphere contains a significant amount of oxygen, which is essential for the process of respiration in living organisms, including humans. Oxygen is used by our bodies to produce energy through cellular respiration.

2. Weather phenomena: The troposphere is where weather occurs. It is the layer where clouds form, precipitation takes place, and most of the Earth's weather patterns develop. The interaction of air masses, temperature variations, and moisture content in this layer creates the diverse weather conditions we experience on Earth.

3. Air pressure and temperature regulation: The troposphere plays a crucial role in regulating air pressure and temperature. As we move higher in the troposphere, the air pressure decreases, and the temperature drops. This decrease in temperature with altitude is known as the lapse rate.

4. Pollution and greenhouse gases: The troposphere is also the layer where pollutants and greenhouse gases accumulate. Human activities, such as burning fossil fuels and industrial processes, release pollutants and greenhouse gases into the troposphere. This leads to air pollution and contributes to global warming and climate change.

Conclusion:
In summary, the air we breathe primarily exists in the troposphere, which is the lowest layer of the Earth's atmosphere. This layer is essential for sustaining life, regulating weather patterns, and influencing climate. Understanding the troposphere helps us comprehend the dynamics of our atmosphere and the impact of human activities on it.