Weather and Climate Ch2

  1. Energy
    An agent capabe of setting an object in motion
  2. Joule
    Standanrd unit of measurement of energy in scientific applications
  3. Power
    rate at which energy is released, transferred, or received.
  4. Watt
    The unit of power
  5. Electromagnetic Radiation
    The energy emitted by the sun and transferred to the Earth. Provides energy for movement of the atmosphere, growth of plants, evaporation of water etc.
  6. Kinetic Energy
    (as opposed to Potential Energy) Energy in use/of motion
  7. Potential Energy
    (as opposed to Kinetic Energy) Energy that hasn't yet been used
  8. Conduction
    (one of 3 energy transfer mecahnisms) The movement of heat through a substance without the movement of molecules in the direction of heat transfer (ex. - a metal rod held partially over fire, part of rod over fire heats, which makes the part of rod not over fire heat as well by heating the molecules next to the ones over the fire)
  9. Convection
    (one of 3 energy transfer mechanisms) The transfer of heat by the mixing of a fluid
  10. Buoyancy
    The tendency for a light fluid (liquid or gas) to float upward when surrounded by a heavier fluid
  11. Radiation
    (one of 3 energy transfer mechanisms) [The only one of the 3 that can occur without a transfer medium] The transfer of energy through empty space.
  12. Wavelength
    the distance between any two corresponding points along the wave
  13. micrometers (microns)
    unit measurement of wavelengths
  14. Blackbodies
    perfect emitters of radiation that emit the maximum possible radiation at every wavelength, purely hypothetical, do not really exist
  15. Stefan-Boltzmann Law
    states that a doubling of temperature produces MORE than a doubling of the amount of radiation emitted.
  16. graybodies
    emit some percentage of the maximum radiation possible at a given temperature (most liquids and solids are graybodies, as blackbodies don't exist)
  17. emissivity
    The percentage of energy radiated by a substance relative to that of a blackbody.
  18. Wien's Law
    tells us that hotter objects radiate at shorter wavelengths than do cool objects.
  19. shortwave radiation
    radiation with wavelengths less than 4 um (microns)
  20. longwave radiation
    radiation with wavelengths longer than 4 um (microns)
  21. Core
    Interior of the sun, where nuclear fusion is produces energy that is ultimately radiated to the Earth.
  22. inverse square law
    states that as the distance of the sun increases, the intensity of the radiation deminishes in porportion of the distnace squared.
  23. solar constant
    the "constant" (steady) solar output of an object
  24. insolation
    the seasonal and latitudinal receipt of incoming solar radiation
  25. ecliptic plane
    The imaginary plane on which Earth orbits the sun for 365 1/4 days (1 year)
  26. revolution
    Earth's annual trip around the ecliptic plane (around the sun)
  27. perihelion
    the point at which Earth is nearest to the sun (around Jan 4)
  28. aphelion
    the point at which Earthh is farthest from the sun (Around July 4)
  29. rotation
    the spinning motion Earth undergoes around its axis every 24 hours
  30. Polaris
    Earth's axis is always pointed in the same direction and always at the same star. This star is called Polaris (The North Star)
  31. June Solstice
    (summer solstice for northern hem, winter for southern hem) The point at which the Northern Hemisphere has its maximum tilt rowards the sun (around June 21), first day of summer
  32. December Solstice
    (winter solstice for Northern Hem, summer sol for southern hem) The point at which Earth is at its minimum availibility of solar radiation
  33. March Equinox and September Equinox
    Intermediate between the two soltices, every place on Earth has 12 hours of day and 12 hours of night
  34. Tropic of Cancer
    23.5 degrees N., the most northward lattitude at which the subsolar point (the point at which the earth and the sun's rays meet at a right angle) is located during the summer solstice. The sun never appears directly overhead above this point.
  35. Tropic of Capricorn
    23.5 degrees S., same as Tropic of Cancer only to the south and occurs during the winter solstice
  36. solar declination
    the latitudinal position of the subsolar point
  37. Arctic Circle
    line of lattitude of 66.5 degrees N.), northern limit of which experiences 24 hours of daylight or darkness
  38. Antartic Circle
    line of lattitude of 66.5 degrees S.), southern limit of which experiences 24 hours of daylight or darkness
  39. Beam Spreading
    the increase in the surface area over which radiation is distributed in response to a decrease in of solar angle. The greater the spreading, the less intense the radiation is.
Card Set
Weather and Climate Ch2
Weather and Climate Ch2