1.3. Cycles and the Earth 1. Water Cycle Water.

1.3. Cycles and the Earth

1. Water Cycle

Water

(1)Evaporation• Heat energy from the sun causes

water in puddles, streams, rivers, seas or lakes to change from a liquid to a water vapor.

• This is called evaporation.

• The vapor rises into the air and collects in clouds.  

(2)Condensation• Water vapor collects in clouds. As the

clouds cool the water vapor condenses into water drops.

• This is called condensation. • These drops fall to the earth as rain,

snow or hail.

(3)Precipitation

• Water falls to the earth from clouds. Mainly as rain, but sometimes as snow and hail.

• This is called precipitation.

(4)Transpiration• Transpiration is the process by which

plants lose water out of their leaves. 

• Transpiration gives evaporation a bit of a hand in getting the water vapor back up into the air.

EvaporationThe vapor rises

CondensationThe Clouds form

PrecipitationThe rain falls

Transpiration

The movement through plants

2. Carbon Cycle

Carbon

Carbon exists in the nonliving environment as:

• Carbon dioxide (CO2)

• Carbonic acid ( HCO3−)

• Carbonate rocks (limestone and coral = CaCO3)

• Deposits of Fossil fuels• Dead organic matter

Organic Carbon

• Hydrocarbons: CH4

• Carbohydrate: CH2O

Inorganic carbon

• Carbon Dioxide: CO2

• Calcium Carbonate: CaCO3

Mandale Limestone Quarry

Carbon reservoirs

Carbon is taken from the atmosphere in several ways

①Photosynthesis.

②The oceans when the seawater becomes cooler, more CO2 dissolve and become carbonic acid.

• In the upper ocean areas organisms convert reduced carbon to tissues, or carbonates.

Photosynthesis

• CO2 + H2O + sunlight CH2O + O2

Respiration

• CH2O + O2 CO2 + H2O + energy

Combustion or Oxidization of hydrocarbon

CH4 + 2 O2 CO2 + 2 H2O + energy

Human Impacts on the Carbon Cycle

Burning fossil fuels have serious impact on the carbon cycle.

Fossil Fuel

86% of global primary energy consumption is fossil fuels.

Fossil Fuels

• Petroleum

• Natural Gas

• Coal

3. The Energy Cycle

• The amount of energy that enters the system should equal the amount that is removed.

• Because of the balance-scale nature of Earth’s energy cycle, scientists also call it Earth’s energy budget.

Three main sources of energy in Earth’s energy budget

• Solar Energy

• Geothermal Energy

• Tidal Energy

<The Law of Thermodynamics>

• Energy can never be created or destroyed, only changed from one form to another.

• When energy changes, it is converted from a more useful, more concentrated form to a less useful, less concentrated form.

→Energy can never be recycled completely.