1. Earth as A Sytsem

2. Closed System Earth is a closed system When thinking this:
We get all of our resources (elements) from here
We are not losing any matter (we cannot exchange matter) ; we can take matter in

3. Greenhouse Gases GHG’s
Move between the four systems:
1. geosphere
2. atmosphere
3. hydrosphere
4. biosphere
GHG’s include: water vapor, nitrous oxide, carbon dioxide, methane, and chlorofluorocarbons

4. Example H2O vapor →condensation→precipitate↓
↑returned to Earth ← drank by animal

5. One change in one system can affect other systems.
Ex:
Clear cutting a forest = more CO2 in the atmosphere because less plants use CO2 in photosynthesis.