Climate And Weather

Troposphere, Stratosphere, Mesosphere, Thermosphere, and Exosphere

The troposphere, which extends from the surface to about 12 km altitude

The boundary between the troposphere and the stratosphere, where temperature stops decreasing with altitude

It contains the ozone layer, which absorbs most of the Sun's harmful ultraviolet (UV) radiation

Temperature decreases with altitude, making it the coldest layer of the atmosphere (down to about −90°C)

Approximately 78% nitrogen (N₂), 21% oxygen (O₂), and 1% other gases including argon and CO₂

Differences in air pressure caused by uneven heating of Earth's surface; air moves from high-pressure to low-pressure areas

The deflection of moving air (and water) due to Earth's rotation — rightward in the Northern Hemisphere and leftward in the Southern Hemisphere

Trade winds (0°–30°), westerlies (30°–60°), and polar easterlies (60°–90°)

A boundary between two air masses of different temperature and humidity (e.g., cold front, warm front, stationary front)

A cold air mass pushes under a warm air mass, causing rapid uplift; it often brings thunderstorms, heavy rain, and a sharp temperature drop

A large body of air with relatively uniform temperature and humidity characteristics, acquired from the region where it forms