Weather and Climate; Temperature and Heat

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Weather and ClimateTemperature and Heat

• Earth and Space Science

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Weather

• The state of the atmosphere at a given time and
  place.

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The 11 Weather Variables

• Air temperature degrees Fahrenheit or Celsius.
• Dewpoint temperature degrees Fahrenheit or
  Celsius. The closer this temperature is to the
  actual air temperature the less dry the air
  feels.
• Relative humidity a between 0 and 100.

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The 11 Weather Variables

• Cloudiness partly cloudy, mostly cloudy,
  overcast, broken, scattered, etc.
• Precipitation Rain, snow, sleet, hail, freezing
  rain, showers, drizzle, ice pellets, etc.
  Measured in inches. 10 inches of snow usually
  melts down to 1 inch of liquid.

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More on the 11 Variables

• Air Pressure Usually measured in millibars (mb).
  Average pressure 1013.2 mb. Low pressures
  950 mb to 1005mb. High pressures 1015mb to
  1040 mb. Under a low pressure area, air is
  rising and as a result, the surface has less air
  molecules than before. Under a high pressure
  area, air is sinking towards the surface and
  piles up before spreading out.

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More on the 11 Variables

• Wind speed Created due to a difference in air
  pressure. Usually measured in miles per hour.
  Most wind speeds range from calm to 20 mph.
  Windiest in between a high and low.
• Visibility how far you can see. Ranges between
  0 and 10 miles. Less in fog and on days when
  there is precipitation. More on days when you
  can see the Sun.

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More on the 11 Variables

• Wind direction The direction the wind is coming
  from. This can be N, S, E, W, NE, NW, SE, SW,
  ENE, SSW, NNW, NNE, etc.
• Wind chill A combination of air temperature and
  winds speed in order to show what the temperature
  feels like.

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More on the 11 Variables

• UV index an index that ranges from 0 to 10. 10
  means your skin may burn very fast due to
  ultraviolet radiation from the Sun. 0 indicates
  a low risk of sunburn.

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The 11 Weather Variables

• Air temperature --click here or click here
• Dewpoint temperature --click here
• Relative humidity --click here
• Cloudiness --click here
• Precipitation --click here
• Visibility --click here
• Air pressure --click here
• Wind speed --click here
• Wind direction --click here
• Wind chill --click here
• UV index --click here or click here

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Abington JR HI Weather

• http//www.instaweather.com/WCAU/default.asp?cid9
  0idABGTNobsfull

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Climate

• Weather conditions at some locality averaged over
  a specified period of time. (example the
  average high temperature for July is 78 degrees
  Fahrenheit.)

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Climate

• Departures from long term averages. (example
  over the past year we are 4.3 inches above normal
  for our precipitation.)
• Weather extremes. (the lowest temperature ever
  recorded in the state of Pennsylvania is -42
  degrees Fahrenheit.)

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Temperature and Heat

• Hey.what is the difference
• between temperature and heat?

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Temperature and Heat

• Heat the amount of kinetic energy in a system.
  Energy in the atmosphere moves in 3 ways.
  Radiation (from the Sun to Earth), conduction (by
  touching something), and convection (air masses
  moving around such as opening a window in the
  winter and making your house cooler.)

• Temperature measurement of the average kinetic
  energy (molecules in motion)in a system.
  Measured in degrees.

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Did You Know

• There is no such thing as cold, only an absence
  of heat.
• There is no such things as darkness, only an
  absence of light.
• There is no such thing as evil, only an absence
  of good.