Chapter 1 Our Planet Earth Chapter 2 Earth Systems

Earth is a complex place Earth is a complex place. It is made up of air, water, land, and living things. Earth is divided into five separate “Systems” to help better understand it. Although each system is very different, they all interact with each other. What happens in one system affects the others.

Hydrosphere Frozen Water Cryosphere Atmosphere Biosphere Geosphere

Atmosphere A layer of invisible gases, solids and some water vapor that surrounds the planet It extends from Earth’s surface up to the edge of space and is pulled to Earth’s surface by the force of gravity It helps regulate Earth’s temperature by trapping and releasing thermal energy from the Sun

Composition of Earth’s Atmosphere Gases – 78% Nitrogen, 21% Oxygen, 1% trace gases such as argon, carbon dioxide and ozone. Solids – small particles of dust, pollution, salt, ash, pollen

Liquids – water vapor ranges from 0-4% depending on the location example: the air over a large body of water will have more water vapor

Layers of the Atmosphere The atmosphere is divided in layers according to differences in temperature Different layers absorb or reflect the thermal energy from the Sun differently

Altitude is the distance from Earth’s surface. Density describes how tightly packed the molecules are As altitude increases, the density of air molecules decrease. This means the air gets “thinner.”

Troposphere The first layer extends to approximately 10km (6 miles) from Earth’s surface Contains all weather and living things Temperature decreases (colder) as the altitude increases

Stratosphere The second layer extends to approximately 50 km (30 miles) from Earth’s surface The gases are stable (calm) and form flat layers

The stratosphere contains a gas known as ozone, which protects Earth by absorbing some of the harmful rays of the Sun. Because ozone absorbs solar radiation, temperatures in the stratosphere increase as altitude in the stratosphere increases

The upper three layers of the Atmosphere Mesosphere -middle layer and coldest layer Thermosphere - hottest layer Exosphere - beyond is outer space

all the water on Earth’s surface and underground Hydrosphere all the water on Earth’s surface and underground the amount of water on Earth never changes, it just flows from one location to another

A reservoir is a natural location of water. 97% of all water on Earth is salty Fresh water picks up minerals and flows into the ocean making it salty

Only 3% of all water is fresh water and able to sustain life It is found in lakes, rivers and underground

Cryosphere All the frozen (solid) water on Earth 79% of all freshwater is trapped in icebergs and glaciers Snow is also considered a solid

Geosphere The largest of Earth’s systems All the solid parts of Earth found on the surface, underground and on the ocean floor Consists of soil, metals, minerals and rocks

Biosphere all living things on Earth This system has no boundaries, living things are found in all the other systems, such as air, water, and soil