TRANSFER OF HEAT ENERGY Heat –the energy transferred between objects that are at different temperatures Heat energy always moves from warmer areas to cooler ones. When objects of different temperatures are near each other, they will exchange heat and may reach thermal equilibrium (the same temperature) over time.

TRANSFER OF HEAT ENERGY Heat energy moves or is transferred throughout the earth’s system in 3 ways: 1. Radiation 2. Conduction 3. Convection

CONDUCTION Conduction The transfer of heat energy through a substance (from particle to particle).

It can take place within the same material. CONDUCTION CONTINUED It can take place between two different materials that are touching (direct contact). Example: your hand gets warm when holding a hot cup of cocoa It can take place within the same material. Example: the handle of a spoon soon gets hot when it is placed in a hot liquid see it in action The heat transfers from atom to atom within the spoon.

CONDUCTORS AND INSULATORS Heat travels easily through some materials. These materials are called conductors. metals are good conductors of heat energy. Solids conduct heat better than liquids or gases. See it. INSULATORS are materials that delay (slow down) the transfer of heat. Most materials are better insulators than conductors. Examples: air, wood, wool, paper, Styrofoam, fur, feathers, glass, plastic, etc.

How do materials get hot through conduction? The atoms and molecules of the substance that are in contact with the heat vibrate, speed up, and bump into nearby molecules transferring their energy. The fast molecules (in the hot substance) slow down and the slow molecules (in the cooler substance) speed up until all of the molecules are all moving at the same speed. This is known thermal equilibrium.

CONVECTION Convection is the transfer of heat from one place to another by the movement of fluids. Fluids can either be liquids or gases. Fluids flow. Convection is caused by uneven heating of a fluid.

CONVECTION When a fluid is heated, it expands, becomes less dense and rises. The cooler fluid moves to the bottom because it is more dense. This exchange of warmer and colder materials creates a convection current. When the fluids move, heat energy is carried from the warm area to the cold.  

CONVECTION, continued . Density refers to how much matter is packed into a space. The more particles in a space, the heavier it becomes, making it more dense.

How does heat get transferred by convection? Convection currents allow fluids to move over great distances such as those which moves heat and air around the globe from the equator to the poles and back to the equator. These are called Hadley Convection Cells

Convection currents in the Ocean and Earth Convection Currents allow fluids to move over large areas Some helpful convection currents on Earth are found in the: Atmosphere. Hydrosphere (ocean) Asthenosphere (mantle)

SEA AND LAND BREEZES DURING THE DAY Because the air over the land is warmer than air over the ocean during the day, a sea breeze is formed. See it. AT NIGHT the land loses heat (cools off) faster than the ocean, so the air over the ocean is now warmer than the air over the land. This causes the convection currents to move in the opposite direction (than in the day) and forms a land breeze.

SEA AND LAND BREEZES

CONVECTION CURRENTS IN THE OCEAN Convection currents can also be found in the ocean, carrying cold water from the polar regions to warmer climates near the equator and from equatorial regions to higher latitudes with cooler climates.

CONVECTION CURRENTS IN THE EARTH They can also be found in the earth’s mantle. This causes the continents to move over the surface of the earth slowly over time. video animation Simulation model Pangaea, an ancient continent, broke up over 200,000,000 years ago and formed the current arrangement of continents as a result of those convection currents.

http://webgeology. alfaweb http://webgeology.alfaweb.no/webgeology_files/english/plate%20tectonics.html

RADIATION Radiation is energy transferred as electromagnetic waves (visible and invisible light such as infrared and ultraviolet light) See ems. Heat can transfer by radiation without touching or moving through any matter. Waves can travel very long distances through empty space (a vacuum). This is how the sun’s energy reaches earth.

INFRARED RADIATION Infrared photo of an ice cube melting Electromagnetic spectrum—infrared waves are larger than visible waves

RADIATION When radiant energy is absorbed by an object it changes to thermal energy and the temperature goes up  Dark colored objects absorb more radiant energy than light colored objects. Light colored objects and shiny objects reflect radiant energy. All objects radiate or give off some amount of electromagnetic energy. Examples: the Sun, light bulbs, fire, people and anything above absolute zero! If you want to keep cool, which would you wear on a sunny day?

Greenhouse Effect—Why does earth experience the greenhouse effect?

Heat budget

http://stephanieloo789.blogspot.com/