Matter, Climate, Water

• Matter


  Anything that occupies space and possesses the attributes of gravity and inertia
• Solid


  • Characterized by resistance to any change in shape
  • Caused by a strong attraction between the molecules of which it is composed
• Liquid


  • Does not resist forces that act to change its shape
  • Molecules are free to move with respect to each other
• Gas


  • Molecules are widely dispersed and freely move
  • Offers no resistance to change of shape and little resistance to change in volume
  • Tends to diffuse infinitely, increasing in volume and diminishing its density
• Plasma


  • The fourth state of matter
  • Consisting of an overall charge-neutral mix of electrons, ions, and neutral atoms
• Density


  The mass of a material divided by its volume
• Solid


  • Has a higher density than a liquid or gas because its particles are very close to one another
• Climate


  The long-term effect of the sun's radiation on the rotating earth's varied surface and atmosphere
• Weather


  The state of the atmosphere at a particular time and place
• Temperature


  A measure of the degree of hotness of the air
• Temperature scales

  • Kelvin (absolute)
  • Celsius (centigrade)
  • Fahrenheit
• Thermometer


  The common instrument used to measure temperature
• Climate


  The long-term effect of the sun's radiation on the rotating earth's varied surface and atmosphere
• Weather


  The state of the atmosphere at a particular time and place
• Elements of weather

  • Temperature
  • Humidity
  • Precipitation
  • Wind
  • Clouds
  • Pressure
• Temperature


  A measure of the degree of hotness of the air
• Temperature scales

  • Kelvin (absolute)
  • Celsius (centigrade)
  • Fahrenheit
• Thermometer


  The common instrument used to measure temperature
• Humidity

  A measure of the amount of water vapor in the air
• Relative humidity


  The amount of vapor in the air divided by the air's vapor-holding capacity
• Relative humidity


  Usually highest around dawn, when the temperature is lowest, and lowest in mid-afternoon, when the temperature is highest
• Hygrometer


  Instrument used in measuring atmospheric humidity
• Psychrometer


  Instrument used in measuring atmospheric humidity
• Precipitation


  Produced when the droplets and crystals in clouds grow large enough to fall to the ground
• Clouds do not usually produce precipitation until they are more than 1 km thick
• Forms of precipitation

  • Raindrop
  • Rain
  • Drizzle
  • Freezing rain
  • Snow
  • Hail
  • Sleet
• Rain gauge


  Instrument used to measure precipitation
• Wind


  The horizontal movement of air
• Wind direction


  Named for the direction from which it comes
• Wind vane


  Instrument used to determine wind direction
• Anemometer


  Instrument used to measure wind speed
• Clouds


  Excess water vapor in the air that condenses into liquid droplets or ice crystals
• Most clouds and almost all precipitation are produced by the cooling of air as it rises
• When air temperature is reduced, excess water vapor in the air condenses into liquid droplets or ice crystals to form clouds or fog
• Cumulus clouds


  • Form from rising masses of air, called thermals
  • Often have a flat base, corresponding to the level at which the water vapor first condenses
  • If a cumulus cloud grows large, it transforms into a cumulonimbus cloud or a thunderstorm
• Cirrus clouds


  • Consist of trails of falling ice crystals twisted by the winds
  • Usually form high in the troposphere, and their crystals never reach the ground
• Stratus clouds

  • Form when an entire layer of air cools or ascends obliquely
  • Often extend for hundreds of miles