Where in the Atmosphere Does Most Weather Occur?

Almost all weather experienced at the Earth's surface is the result of what is occurring in the troposphere, which is the lowest layer of the atmosphere. Rising to a level between 4 to 12 miles above the Earth's surface, the troposphere contains 75 to 80 percent of the entire mass of the atmosphere. Nearly all of the atmosphere's dust particles and water vapor are within the troposphere, which results in this layer also containing the greatest number of clouds.

Water vapor plays a major role in the creation of weather. Air pressure, temperature and the concentration of particulates in the troposphere also drive weather patterns. Particulates in the troposphere actually consist of much more than dust. Pollution, fossil fuel combustion, pollen, spores and volcanic eruptions are some of the sources of the particulates that are concentrated in the troposphere.

The temperature in the troposphere is the result of heat originally absorbed from sunlight radiating from the ground. As the air is heated, it expands and lowers the air pressure. The heated air also rises and causes the movement of air masses. The different pressure systems, their movements and their interactions with each other combine with varying degrees of moisture content to create many of the weather patterns occurring in the troposphere.