1. Earth’s Natural Cycles
Water (H2O) Cycle
Carbon Dioxide/Oxygen (CO2/O2) Cycle
Nitrogen Cycle

2. Water (H2O) Cycle
Water cycle-the movement of water from Earth’s surface into the atmosphere and back to the surface again.
Condensation
Precipitation
Evaporation
Transpiration

3. Water -H20- Cycle is the movement of water in the environment
75% of the Earth’s surface is water.
Most of the Earth’s fresh water is found in frozen polar ice caps and glaciers.
1% (of the 75%) is freshwater
All the water on Earth today is the same water that was here billions of years ago.
Condensation-water vapor turns back into liquid water in the process of condensation.
Precipitation - any form of water (rain, sleet, snow, etc…) that falls from the clouds
Evaporation- process by which a liquid changes into a gas.
Transpiration- The loss of moisture from the leaves of plants.

9. Carbon Dioxide/Oxygen (CO2/O2) Cycle
Carbon Dioxide- An odorless gas in the air which is made out of carbon and oxygen – CO2.
Carbon dioxide is stored mostly in oceans (90% of oxygen in the atmosphere comes from photosynthesis of microscopic plantlike organisms in the ocean) and the atmosphere – it is found in bodies of dead organisms and is a by-product of combustion.
Carbon dioxide and oxygen stay in balance through the process of photosynthesis and respiration
Green plants- take in carbon dioxide and release oxygen

13. Carbon Dioxide/Oxygen Cycle
Sun Plants Rabbit Hawk
Carbon Dioxide