Lecture 9: Atmospheric Temperature, Pressure, Density, and Gases

A collection of vocabulary flashcards based on atmospheric science concepts from Lecture 9.

Atmospheric Pressure

The force exerted by air molecules pressing down against Earth's surface, typically around 1000 millibars.

Equilibrium

A state where the inward pressure from bodily fluids is balanced by external atmospheric pressure.

Altitude

The height above sea level; atmospheric pressure decreases with increasing altitude.

Tropopause

The upper boundary of the troposphere, its height varies with latitude.

Troposphere

The lowest layer of Earth's atmosphere, where most weather phenomena occur.

Conduction

Heat transfer through direct contact; it is inefficient in atmospheric processes.

Convection

Heat transfer by the movement of air, which is an efficient process in the atmosphere.

Exponential Decay

A decrease at a rate proportional to its current value; a concept relevant to atmospheric pressure changes with height.

Adiabatic Expansion

The process where air rises and cools without heat exchange with the environment.

Adiabatic Compression

The increase in air temperature that occurs when air is pushed down without adding heat.

Lapse Rate

The rate of temperature change in the atmosphere with increasing height.

Sensible Heat

The heat that can be felt and measured; related to air temperature.

Latent Heat

The heat absorbed or released during phase changes of water.

Saturation Point

The maximum amount of water vapor air can hold at a given temperature.

Supersaturation

A condition where air holds more moisture than it can typically sustain, leading to condensation.

Nitrogen (N₂)

The most abundant gas in the atmosphere, making up approximately 78%.

Oxygen (O₂)

The second most abundant gas in the atmosphere, comprising about 21%.

Carbon Dioxide (CO₂)

A trace greenhouse gas in the atmosphere, currently around 420 parts per million.

Chlorofluorocarbons (CFCs)

Gases that contribute to ozone layer depletion and increase skin cancer risks.

Ozone Layer

A layer in the atmosphere that absorbs most of the sun's harmful ultraviolet radiation.

Seasonal Variation of CO₂ Levels

Fluctuations in CO₂ concentration that typically peak in late spring and decline in summer.

Ozone Hole

Regions with significantly lower ozone concentrations found primarily at the South Pole.