L4: Atmospheric Composition and Radiative Balance

Troposphere

Lowest atmospheric layer, temperature decreases with altitude.

Stratosphere

Layer above troposphere, temperature increases with altitude.

Residence Time

Average duration an atom spends in a reservoir.

Coefficient of Variation

Standard deviation divided by mean.

Nitrogen Gas (N2)

Major atmospheric component, inert with long residence time.

Water Vapor

Varies 0-4% in atmosphere, short residence time.

Carbon Dioxide (CO2)

Residence time of 3-5 years, influenced by natural processes.

Ozone (O3)

Blocks UV radiation, produced and destroyed in cycles.

Volatile Organic Carbon (VOC)

Gaseous organic compounds affecting air quality.

Electromagnetic Radiation

Radiation emitted by objects based on temperature.

Greenhouse Effect

Traps IR radiation, warming Earth's surface.

Radiative Balance

Equilibrium of incoming solar and outgoing IR radiation.

UV Radiation

High-energy light damaging to living organisms.

Infrared Radiation (IR)

Longer wavelengths emitted by Earth, absorbed by gases.

Ozone Depletion

Reduction of stratospheric ozone due to human activities.

Ozone Formation

O2 splits into radicals, forms O3 in stratosphere.

Atmospheric Composition

Mixture of gases defining atmospheric properties.

Solar Radiation

Energy from the sun, crucial for Earth's climate.

Aerosols

Tiny particles in the atmosphere, can be natural or human-made.

Primary Aerosols

Directly emitted particles like soot and dust.

Secondary Aerosols

Formed from chemical reactions in the atmosphere.

Albedo

Reflectivity of Earth's surface affecting energy balance.

Chemical Processes

Reactions in the atmosphere influenced by solar radiation.

Long-lived Constituents

Atmospheric components with residence times over 7,000 years.

Short-lived Constituents

Atmospheric components with residence times under 10 years.

Dynamic Equilibrium

State where inputs and outputs balance over time.

Heat Release

Energy emitted as heat during atmospheric reactions.

Atmospheric Reservoir

Storage of gases within the atmosphere.

Photochemistry

Chemical reactions initiated by light, affecting air quality.