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Atmosphere: Composition, Structure, and Temperature

Introduction

The atmosphere is the gaseous envelope surrounding the Earth, held by gravity. It plays a critical role in sustaining life, regulating climate, and protecting the Earth from harmful solar radiation. Its composition, vertical structure, and thermal characteristics form the foundation of climatology and weather studies.

Composition of the Atmosphere

Major Constituents (by volume)

Gas	Formula	Percentage	Key Role
Nitrogen	N₂	78.08%	Diluent; essential for plant nutrition (via fixation)
Oxygen	O₂	20.95%	Respiration, combustion
Argon	Ar	0.93%	Inert gas
Carbon Dioxide	CO₂	0.04% (415 ppm)	Greenhouse gas; photosynthesis
Neon	Ne	0.0018%	Trace

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Atmosphere: Composition, Structure, and Temperature

Introduction

Composition of the Atmosphere

Major Constituents (by volume)

Gas	Formula	Percentage	Key Role
Nitrogen	N₂	78.08%	Diluent; essential for plant nutrition (via fixation)
Oxygen	O₂	20.95%	Respiration, combustion
Argon	Ar	0.93%	Inert gas
Carbon Dioxide	CO₂	0.04% (415 ppm)	Greenhouse gas; photosynthesis
Neon	Ne	0.0018%	Trace

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Atmosphere: Composition, Structure, and Temperature

Atmosphere: Composition, Structure, and Temperature

Introduction

Composition of the Atmosphere

Major Constituents (by volume)

This note is temporarily free

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Atmosphere: Composition, Structure, and Temperature

Atmosphere: Composition, Structure, and Temperature

Introduction

Composition of the Atmosphere

Major Constituents (by volume)

This note is temporarily free

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Variable Components