Atmospheric Composition and Structure

Vocabulary flashcards detailing the atmospheric divisions, constant gases, variable gases, inert gases, non-gaseous particles, and pollutants based on the lecture notes.

Heterosphere

The upper section of the atmosphere located above $100\,\text{km}$ above the Earth's surface, where the chemical composition of the different gases varies.

Turbopause

The boundary surface situated between the divisions of the atmosphere, separating the lower atmospheric layer from the heterosphere.

Nitrogen ($N_2$)

A constant atmospheric gas making up $78{,}09\%$ by volume; it is mainly passive regarding weather and climate, and is needed for plant growth.

Oxygen ($O_2$)

A constant atmospheric gas comprising $20{,}95\%$ by volume that is produced by photosynthesis and reduced by deforestation.

Water vapour ($H_2O$)

A variable gas making up $0{,}03\%$ (which can rise to $4{,}0\%$) by volume; it acts as the source of cloud formation and precipitation, reflects/absorbs incoming radiation, keeps global temperatures constant, is essential for life on Earth, and can be stored as ice or snow.

Carbon dioxide ($CO_2$)

A variable gas accounting for $0{,}03\%$ by volume; it absorbs long-wave radiation from the Earth contributing to the 'greenhouse effect', is used by plants for photosynthesis, and is increased by burning fossil fuels and deforestation.

Ozone ($O_3$)

A variable gas constituting $0{,}00005\%$ by volume that absorbs incoming ultraviolet radiation and is reduced or destroyed by chlorofluorocarbons (CFCs).

Argon ($Ar$)

An inert or noble gas that constitutes $0{,}93\%$ of the atmosphere by volume.

Non-gases (dust, salt, and smoke particles)

Trace atmospheric particulates derived from volcanoes, meteorites, and wind soil erosion; they absorb/reflect incoming radiation and form condensation nuclei necessary for cloud formation.

Pollutants (sulphur dioxide, lead)

Trace atmospheric substances originating from industry, power stations, and car exhausts that affect radiation and cause acid rain.