Meteorology Study Guide

Exam Notes and Study Guide

A. What gases make up the atmosphere? Which have uniform distribution? Which vary in concentration? What are aerosols?

  1. Nitrogen, Oxygen, and Argon have uniform distribution while gasses like methane, ozone, water vapor, and carbon dioxide vary

B. How does temperature vary with height in the atmosphere?

  1. As altitude increases, temperature decreases

C. What do weather instruments do? Thermometer, hygrometer, barometer, radiosonde, radar, satellites, etc….

  1. Thermometer
    1. Measures the air temperature
  2. Hygrometer
    1. Moisture content in the air
  3. Barometer
    1. Measures air pressure
  4. Radiosonde
    1. Measures altitude, air pressure, relative humidity, wind, and cosmic rays at higher altitudes

Terms

  1. Define heat and temperature.
  2. Heat is a form of energy transferred between systems by their temperature
  3. Temperature is the average speed of molecules and atoms
    1. Hot means that the molecules are moving at a faster rate
  4. Define absolute zero.
    1. The lowest temperature that is theoretically possible

Concepts

  • Know the boiling and freezing point of water on various temperature scales.

Boiling Points Freezing Points

212 Farenheight 32 Degrees Farenheight

100 Degrees Celsius 0 Degrees Celsius

  1. Know the difference between a conductor and an insulator (heat).
    • A conductor allows heat to transfer/travel through it while an insulator traps heat
  2. How is heat or energy transferred?
    • Through conduction, heat travels from hotter areas to colder areas (this is also known as the law of entropy in thermodynamics)
  3. Be familiar with Stefan Boltzman’s Law (how are energy and temperature related) and Wein’s Law (how is temperature related to the wavelength of energy emitted by an object).
  4. Stefan Boltzman’s Law
    1. The amount of radiant energy emitted from a unit surface area of an object is proportional to the fourth power of the object's absolute temperature
  5. Wein’s Law
    1. The wavelength of maximum emitted radiation by an object is inversely proportional to the object’s absolute temperature

Describe the relationship between wavelength and frequency of radiation.

The more light an object absorbs of a given wavelength the more likely that object is an emitter of that particular wavelength

Chapter 3

Terms

  1. Define perihelion and aphelion.
    1. Perihelion
      1. The Point in Orbit in which a planet, asteroid, or object is the closest in relation to the sun
    2. Aphelion
      1. The Point in Orbit in which a planet, asteroid, or object is the farthest in relation to the sun
  2. What is reflection (albedo), transmission, and absorption?
    1. Reflection Albedo
      1. The fraction of solar energy that is reflected by an object
    2. Transmission
      1. The ability of light to penetrate an object
        1. The light may either reflect or scatter based on the wavelength
  3. What is Raleigh and Mie scattering?
    1. Raleigh
      1. The scattering of light by particles in a wavelength without a change in wavelength
    2. Mie
      1. Elastic scattered light of particles that have a diameter similar or larger than the wavelength of the incident light
        1. Mie signal is proportional to the square of the particle diameter

Concepts

  1. What are the dates for the seasons in the northern and southern hemispheres? How does that influence the length of the day?
    1. Northern Hemisphere
      1. March 21ish - Spring
      2. June 21 - Summer Solstice
      3. September 22 - Autumn
      4. December 21 - Winter Solstice
    2. Southern Hemisphere
      1. March 21ish - Autumn
      2. June 21st - Winter Solstice
      3. September 22nd - Spring
      4. December 21st - Summer
  2. What is the difference between a continental and maritime climate?
    1. Maritime
      1. Influenced by the surrounding ocean
    2. Continental
      1. Influenced by surrounding land mass
  3. What happens to radiation in the atmosphere?
    1. Some is reflected off clouds, some is absorbed into atmosphere, and the rest hits Earth
  4. The sun emits in the visible portion of the electromagnetic spectrum, while Earth emits in the infrared.

Chapter 4

Terms

  1. Define evaporation, condensation, precipitation, and sublimation(phase changes of water).
    1. Evaporation
      1. Water droplets rise due to heat
    2. Condensation
      1. Water droplets/vapor transform into liquid
    3. Precipitation
      1. Water falls down in form of hail, snow, or rain
    4. Sublimation
      1. The conversion of an object from solid to gaseous form without the stage of a liquid
  2. Define saturation(saturation → evaporation = condensation).
    1. Saturation
      1. The condition at which the air has the capacity to contain all the water vapor possible in a given area
  3. Define dewpoint and wet-bulb temperature.
    1. Dewpoint
      1. The temperature to which air would have to be cooled for saturation to occur
    2. Wet bulb Temperature
      1. The temperature of thermometer that is covered in a wet cloth at 100% humidity, this temperature will always be lower than the actual air temperature

Concepts

  1. For water vapor → What is mixing ratio, specific humidity, and vapor pressure?
    1. Mixing ratio is the ratio of water to air in a given parcel
    2. Specific Humidity is the mass of water droplets in a parcel of air
    3. Vapor Pressure is the pressure that water vapor molecules would exert if the air were saturated with vapor at a given temperature
  2. How is water vapor in the atmosphere measured?
    1. Water vapor in the atmosphere is measured through hygrometers
  3. How is relative humidity calculated? Know the formula.
    1. Relative Humidity is the humidity that is measured in comparison to the maximum amount of humidity that can exist in a given space
    2. The formula is relative humidity = (specific humidity) / (saturation point) x 100.
  4. How does the saturated mixing ratio or vapor pressure relate to temperature? How does mixing ratio or vapor pressure relate to dewpoint?
    1. As vapor pressure increases, so does the temperature
    2. Mixing ratio and vapor pressure relates to temperature because as the pressure increases, the dew point rises
  5. How does water vapor affect the density of air?
    1. The amount of water vapor in the air determines how dense the air is because it takes up space
  6. How do temperature and humidity change during the day?
    1. Temperature and humidity change as the temperature changes due to the rising and setting of the sun
  7. How does saturation vapor pressure relate to temperature?
    1. Saturation vapor pressure relates to temperature because as temperature increases, saturation vapor pressure drastically rises

Chapter 5

Terms

  1. Low, Middle, and High clouds → What are they composed of? What are their general heights?
    1. Low
      1. Surface to 6500 Ft, composed of water droplets
    2. Middle
      1. 6500-25000 Ft
    3. High Clouds
      1. 16,000 to 43,000 Ft.
      2. Composed of ice crystals
  2. Know what “cirro” → feathery “alto” → high “strato” → sheetlike “cumulo” → heaped “nimbo” → dark mean.
    1. Cirro Clouds
      1. Latin for curly hair, relating to wispy clouds
    2. Stratus Clouds
      1. Latin for layer or sheetlike
    3. Cumulo Clouds
      1. Heaps, wide clouds that appear to be stacked on one another in a wide expansion
    4. Nimbo
      1. Dark clouds, carry precipitation
  3. Know what various unusual clouds are: lenticular, noctilucent, etc.
    1. Lenticular Clouds
      1. Clouds that form into the shape of a lens, people most likely mistake these for UFOs
    2. Pileus
      1. The cloud that forms a cap over a mountain
    3. Mammatus Clouds
      1. Clouds that appear to have sacks hanging from under them
    4. Noctilucent Clouds
      1. Wavy thin clouds appear during twilight hours