Earth's Atmosphere Overview

Year 10 Combined Science Understanding our protective blanket Composition, structure, and importance

What is the Atmosphere?

A layer of gases surrounding Earth Held in place by gravity Essential for life as we know it Protects us from harmful radiation Regulates Earth's temperature

Atmospheric Composition

Nitrogen (N₂) - 78% Oxygen (O₂) - 21% Argon (Ar) - 0.9% Carbon dioxide (CO₂) - 0.04% Trace gases - water vapor, neon, helium

Layers of the Atmosphere

The Troposphere

Lowest layer (0-12 km) Where we live and breathe Contains most water vapor All weather occurs here Temperature decreases with altitude

The Stratosphere

Second layer (12-50 km) Contains the ozone layer Protects us from harmful UV radiation Temperature increases with altitude Very dry with few clouds

The Greenhouse Effect

"The atmosphere acts like a blanket, trapping heat to keep Earth warm enough for life."

Human Impact on the Atmosphere

{"left":"Burning fossil fuels increases CO₂\nDeforestation reduces CO₂ absorption\nIndustrial processes release pollutants\nVehicle emissions contribute to smog\nCFCs damage the ozone layer","right":"Enhanced greenhouse effect\nGlobal temperature rise\nAir quality problems\nOzone depletion\nClimate change effects"}

Data Analysis: CO₂ and Temperature

Work in pairs with the data worksheet Analyze historical CO₂ levels and temperature changes Look for patterns and trends Connect changes to human activities Prepare to share your findings

Quick Quiz - Test Your Knowledge!

1. What is the most abundant gas in the atmosphere? 2. Which layer contains the ozone that protects us? 3. Why is the greenhouse effect important? 4. Name two human activities that increase atmospheric CO₂ Use your mini whiteboards!