Overview
This lecture covers the Earth's subsystems, their definitions, examples, and how they interact within the planet's system.
Earth's Subsystems
- The Earth is composed of four main subsystems: geosphere, hydrosphere, atmosphere, and biosphere.
- These subsystems interact to support life and create environmental processes.
Geosphere
- The geosphere includes all solid parts of the Earth, such as rocks, soil, and landforms.
- It consists of the crust, mantle, and core.
Hydrosphere
- The hydrosphere encompasses all of Earth's water, including oceans, rivers, lakes, groundwater, and glaciers.
- It regulates temperature and supports aquatic life.
Atmosphere
- The atmosphere is the layer of gases surrounding Earth, mainly nitrogen, oxygen, and trace gases.
- It protects against harmful solar radiation and enables weather and climate.
Biosphere
- The biosphere includes all living organisms and the environments where they live.
- It relies on and influences the other subsystems for energy and resources.
Interaction Between Subsystems
- Energy and matter are exchanged among the subsystems, creating complex cycles (e.g., water cycle).
- Changes in one subsystem (e.g., volcanic eruption) can impact the others (e.g., atmosphere, biosphere).
Key Terms & Definitions
- Geosphere — solid parts of Earth (rocks, soil, crust, mantle, core)
- Hydrosphere — all water on Earth (liquid, solid, vapor)
- Atmosphere — layer of gases around Earth
- Biosphere — all living organisms and their environments
Action Items / Next Steps
- Review the four subsystems and their characteristics
- Prepare examples of each subsystem for class discussion