describe what happens to solar energy that reaches earth summarize the processes of radiation,...
TRANSCRIPT
Atmospheric Heating
S6E4.a Demonstrate that land and water absorb and lose heat at different rates and explain the resulting effects on weather patterns.
• Describe what happens to solar energy that reaches Earth• Summarize the processes of radiation,
thermal conduction, and convection• Explain the relationship between the
greenhouse effect and global warming
Energy in the Atmosphere
• Earth and it’s atmosphere are warmed by energy from the sun.• We are going to discuss the three ways that this happens: radiation, conduction, and convection.
Radiation: Energy Transfer by Waves• RADIATION is the
transfer of energy as electromagnetic waves
• Radiation is how energy from the sun reaches Earth.
• Energy from the Sun is absorbed by the atmosphere, land, and water and converted into thermal energy
• The earth receives only about 2 BILLIONTHS of the energy radiated by the sun.
Radiation: Energy Transfer by Waves
Ex.Sun’s rays
traveling through space
to Earth.
Conduction: Energy Transfer by Contact
• THERMAL CONDUCTION is the transfer of thermal energy through a material by DIRECT CONTACT
• Thermal energy is always transferred from warm to cold areas
• When air molecules come into DIRECT CONTACT with the warm surface of earth, thermal energy is transferred to the atmosphere.
Conduction: Energy Transfer by Contact
In what ways have you
experienced conduction?
Think back….what is this called?
Convection: Energy Transfer by Circulation
Convection: Energy Transfer by Circulation
• CONVECTION is the transfer of thermal energy by the circulation or movement of a liquid or gas•MOST thermal energy in the atmosphere is transferred by CONVECTION
Convection: Energy Transfer by Circulation
• Circulation of hot & cold air: •As air is heated it becomes less dense and rises•Cool air is denser so it sinks•as the cool air sinks it pushes the warm air up.
• This cycle of warm air rising and cool air sinking causes a circular movement of air called a CONVECTION CURRENT
Greenhouse Effect
GreenhouseEffect
70% of the solar radiation which enters Earth’s atmosphere is absorbed by the clouds and Earth’s surface.
Likewise, the Earth’s surface re-radiates thermal energy. Most of this thermal energy is absorbed by gases in the atmosphere and radiated back to Earth’s surface instead of into space.
Greenhouse EffectWhat is the greenhouse effect? the warming of the surface and lower atmosphere of Earth that occurs when water vapor, carbon dioxide, and other gases absorb and reradiate thermal energy.
Greenhouse EffectAnd This: Atmosphere acts like glass walls and roof of a greenhouse, allowing solar energy to enter, but prevents thermal energy from escaping.
Global WarmingGlobal Warming: a gradual increase in average
global temperature due to the increase of greenhouse gases in the atmosphere that absorb thermal energy
What has increased the greenhouse gases?1. Increased use of fossil fuels= more
carbon dioxide in air 2. Deforestation-=less trees= more
carbon dioxide in air
Add carbon dioxide molecules to the airin your drawing.
