Earth’s Atmosphere and Climate Systems Explained — Layers, Circulation, and Weather Hazards | Chapter 20 from Earth: Portrait of a Planet
Earth’s Atmosphere and Climate Systems Explained — Layers, Circulation, and Weather Hazards | Chapter 20 from Earth: Portrait of a Planet What keeps our planet habitable, drives the weather, and shapes global climate? Chapter 20 of Earth: Portrait of a Planet by Stephen Marshak explores the Earth’s atmosphere—from its origins and structure to the global systems that produce everything from jet streams to hurricanes. For an in-depth podcast summary, watch the chapter video on YouTube , or read below for a complete educational overview. The Evolution and Composition of Earth’s Atmosphere Evolution: Earth’s atmosphere began with loss of hydrogen and helium, followed by volcanic outgassing of CO₂ and H₂O, and was transformed by the Great Oxygenation Event caused by cyanobacteria. Modern Atmosphere: Composed mostly of nitrogen and oxygen, with trace greenhouse gases and aerosols that regulate temperature. Layers of the Atmosphere and Their Functions Troposphere: Cl...