Earth System Interactions

Earth's Spheres

• Earth is divided into four interacting spheres: atmosphere, biosphere, cryosphere, geosphere, and hydrosphere.
• A change in one sphere affects all other spheres.

Atmosphere

• The atmosphere is the air surrounding Earth, extending from the surface to outer space.
• It consists of gases and particulate matter and protects Earth's surface from radiation.
• Nitrogen ($78\%$) and oxygen ($21\%$) are the most abundant gases.

Hydrosphere

• The hydrosphere includes all water on Earth (oceans, lakes, rivers, streams, ice).
• $71\%$ of Earth's surface is covered in water.
• The cryosphere is the frozen portion of the hydrosphere (icebergs, glaciers, ice caps).
• $97\%$ of Earth's water is saltwater, and less than $1\%$ is liquid freshwater.

Biosphere

• The biosphere includes all living organisms in the air, on land, and in water.
• It is made up of plants, animals, and bacteria.

Geosphere

• The geosphere is the mostly solid part of Earth, including rocks, minerals, and landforms.
• It also encompasses Earth's interior, which contains some liquid.

Sphere Interactions

• Sphere interactions are processes that move matter and energy between spheres.
• Photosynthesis: Plants (biosphere) use carbon dioxide (atmosphere), water (hydrosphere), and nutrients (geosphere) to make food, releasing oxygen (atmosphere).
• Volcanic eruptions (geosphere) release particles into the atmosphere, increasing rainfall (hydrosphere) and plant growth (biosphere).
• Human activities, like building dams (geosphere), can impact sphere interactions by altering water flow (hydrosphere) and energy use (biosphere).