Unit 5: Radiation & Heat Balance Flashcards
What is energy? Where does it come from?
Energy is the ability to do work or cause change. Energy comes from the Sun in the form of electromagnetic energy (radiation, light.)
What is radiation?
Radiation is the transmission of energy in the form of electromagnetic waves. All objects lose heat (thermal energy) by radiation.
Where does shortwave radiation come from?
Shortwave radiation comes from the Sun. It is also called solar radiation.
Of all incoming solar radiation, only 30% travels directly to Earth’s surface– this is called direct radiation. There is also diffuse radiation, which is when energy is reflected and scattered.
Where does longwave radiation come from?
Longwave radiation comes from Earth. Also called terrestrial radiation. The lower the temperature, the longer the wavelength.
Outgoing longwave radiation is absorbed by gases in the atmosphere
What two things can happen when radiation strikes Earth?
It can be absorbed by - and then heat - Earth’s surface
Or it can be reflected by the surface, and there is no heating effect
What’s the different between between HEAT and TEMPERATURE?
Heat is energy being transferred between two objects because the two objects have a different temperature.
Temperature is the average kinetic energy (speed movement) of the random motion of the individual molecules that make up a substance.
What are the five methods of heat transfer?
- Conduction
- Convection
- Advection
- Latent Heat
- Radiation
What’s the difference between sensible and latent heat?
Sensible Heat: Heat transfer that takes place when air or water at one temperature moves to a location with a difference temperature.
Latent Heat: Heat transfer associated with the flow of water vapor. It can be vertical or horizontal.
Define conduction.
Conduction is an energy transfer accomplished by contact between individual molecules.
Define convection and advection.
Convection is energy transfer is accomplished by the flow itself. It is vertical. Advection is the transfer of heat by horizontal currents in either a fluid or gas.
What is albedo? What is the albedo of a snowy surface?
Albedo is the proportion of incoming radiation that is reflected by a surface. The albedo of a snowy surface is about 80%.
Where is there a surplus of energy? A deficit?
Areas within 40 degrees latitude have a surplus of energy. There’s an energy deficit between 35N and the North Pole, and 35S and the South Pole.
Why do the surplus and deficit areas not heat up/freeze?
Heat moves poleward within the Earth’s system from lower to higher latitudes to provide an energy balance.
Transporting mechanisms: wind, ocean currents, storm systems.
What’s the Atmospheric Greenhouse Effect?
It is the recycling of energy. Some outgoing radiation is absorbed by gasses in the atmosphere (Greenhouse Gases), redirect energy back to the surface of the Earth (and out to space).
What’s the Enhanced Greenhouse Effect Theory?
An increase in a certain greenhouse gases in the atmosphere may lead to an increase in the amount of longwave radiation emitted by the Earth.
