ch 18 20

  1. air pressure
    is just the pressure exerted by the weight of the air above
  2. pressure
    is defined as force per unit area
  3. barometer
    is the instrument used to measure air pressure.
  4. 2 types of barometers
    mercury(liquid ) aneroid (without liquid)
  5. mercury barometer
    the pressure rises the level of mercury in the column rises and as the pressure drops the level falls.
  6. aneroid barometer
    there is no liquid and is small and portable. It has a pointer with a dial calibrated to read in inches or millibars
  7. wind
    air moving horizontally along the earths surface.
  8. Pressure Gradient Force
    It is the driving force of wind as it has both direction and magnitude. Air pressure always moves from a region of higher air pressure to a region of lower pressure. When isobars (lines connecting points of equal pressure) are very close to one another then they indicate a sharp pressure gradient.
  9. coriolis effect
    Free moving fluids or objects are deflected to the right in the Northern Hemisphere and to the left in the Southern hemisphere because of earth’s rotation
  10. Friction with the Earth’s Surface:
    This acts to slow air movement. The frictional effect is low in flat surfaces and high in mountainous regions.
  11. lows
    are also called cyclones and arre centers of low pressure
  12. highs
    are also called anticuclones and are regions of high pressure
  13. Anticyclonic Winds
    When the wind swirls clockwise in the northern hemisphere or counter-clockwise in the southern hemisphere
  14. Cyclonic
    When the wind swirls counter-clockwise in the northern hemisphere or clockwise in the southern hemisphere,
  15. Subsidence
    associated with cloudy skies
  16. Air that is rising is associated
    with precipitation and cloudy skies.
  17. nonrotating earths circulation
    It has the upper-level air moving towards the pole and surface air moving towards the equator.
  18. Global Circulation Idealized: Encompasses the
    following zones
    • Equatorial Low
    • Subtropical High
    • Trade Winds
    • Westerlies
    • Polar Easterlies
    • Polar Front
  19. Equatorial Low
    Regions known by alot of precipitation as the air is rising
  20. Subtropical High
    Found around 30° latitude N and S of the equator. Locations of the major deserts of the world (Arabia, North Africa, Australia), owing to stable dry stable conditions.
  21. Trade Winds
    Air deflicted by the Coriolis effect associated with traid and commerce
  22. westerlies
    the air remaining from the trade winds traveling towards the poles fould in teh mid latitude regons
  23. polar easterlies
    formed as a result of westerlies moving polewards
  24. polar front
    formed as a result of warm and cold fronts
  25. influenced of contients
    Produced by high and low pressure over the oceans and pressure changes over land. Extremes of climate and ranges of temperatures.
  26. Westerlies
    In the Northern Hemisphere, these cells move from west to east that create an anticyclonic or clockwise flow or cyclonic or anticlockwise flow in their path
  27. Wind vane
    used to measure wind direction
  28. anemometer (anemo meaning wind and metron meaning instrument)
    used to measure wind speed.
  29. El nino
    Name given to periodic warming of oceans occurring in the eastern and central Pacific resulting in extreme weather.
  30. La nina
    Occurs in the central and eastern Pacific region as a result of unusually low sea-surface temperatures and strong trade winds.
    This is influenced by wind and air pressure, the distribution of water and land and latitude.
  32. air pressure
    the pressure exerted by the weight of the air above.
  33. pressure
    defined as force per unit area (pressure in tires).
  34. air mass
    • the terms given to a large body of air about 1000 miles in extent or more and several miles thick, characterized by similar moisture and temperature patterns regardless of
    • altitude
  35. Source Regions
    the region where the air mass gains its properties of moisture and temperature
  36. Polar (P)
    air masses originate in high latitudes towards the poles
  37. tropical (T)
    which form in low latitudes
  38. Contiental (c)
    air masses that formed on land
  39. maritime (m)
    that originate over water
  40. Continental air is more
  41. maritime
    more humid
  42. continental polar air originating in Canada is responsible for
    cold temp and no precipitation
  43. lake affect
    • air masses that cross the Great Lakes during
    • winter
  44. Essay what is a front and 4 kinds
    The leading edge of an advancing air mass
  45. warm front
    When the position of a front moves such that warm air occupies the position formerly occupied by cooler air
  46. cold front
    When the position of a front moves such that cold air occupies the position, formerly occupied by warmer air
  47. stationary front
    what the flow is neither towards a warm or a cold air mass
  48. occluded front
    when a cold front actively surpasses a warm front
  49. middle latitude cyclones
    These are centers of low pressure that move from west to east and can last from a few days to a week to ten days. They are broken up into three stages: youth, maturity, and old age
    Is simply the storm associated with lightening and thunder. It also frequently produces heavy rain, hail, and gusty winds. They form when humid, warm air rises in an unstable environment.
  51. tornadoes
    Are local storms of short duration ranking among nature’s most destructive forces. They are violent windstorms that take the form of a rotating column. Can produce high winds, heavy rainfall, and damaging hail.
  52. hurricanes
    Are whirling tropical cyclones having wind speeds of about 185miles per hour and constitute one of the greatest storms on earth and can result in billions of dollars worth of damage.
  53. climate
    includes atmosphere, hydrosphere, geosphere, biosphere, and cryosphere (ice and snow on the earth’s surface).
    Temperature and precipitation are the most important features when it comes to describing climatic characteristics for any place in the world as they have an impact on people and their lifestyle and activities. This leads us to classification for climate.
  55. climate classification
    The best known climate classification system generally accepted is the Köppen classification
  56. Essay 3 classification and 6 types
  57. classification
    average monthly temperature, average monthly precipitation, and total annual precipitation
  58. 6 types of boundaries
  59. A: Humid Tropical
    No winters, temperature hardly ever falls below 64°.
  60. C: Humid Mid-Latitude (Mesothermal):
    Mild winters, the average coldest month is below 64°F but above 27°F.
  61. D: Humid Mid-Latitude (Microthermal):
    Severe winters, the average temperature of the coldest month is below 27°F.
  62. E: Polar:
    Summerless climates, the average temperature of the warmest month is below 50°F
  63. B: Deserts
    Classified on the basis of precipitation. Constitutes the warm desert regions of the world.
  64. H: Highlands:
    Is the climate associated with a region of high elevations as compared to the regions of the same latitude located at lower elevations.
  65. A: Humid Tropical:
    Most extensive, occupies 36% of the earth’s land surface. They extend from 20°N to 20°S. Consistent daylength and therefore, a constant amount of energy from the sun
  66. C-Humid Mid-Latitude:
    Occupies 27% of the earth’s land area but 55% of the earth’s population. These are regions of great weather variability and therefore, greater air mass conflicts. Differences in seasonality is evident as is reflected in the type of soil, vegetation, and human life.
  67. D-Humid Mid-Latitude
    Have long winters covers almost 21% of the earth’s land surface. They experience greater temperature ranges on the basis of continentality.
  68. E-Polar
    Have no actual summers. These are regions of permafrost. Average monthly temperatures, in the summer temperatures hardly ever rise beyond 50°F.
  69. B-Deserts:
    Covers 35% of the earth’s land surface. Classified on the basis of precipitation. The plant and animal life is unique to these regions as they have to adapt to the conditions
  70. H-Highlands
    Difference in range of temperatures are higher for elevated regions as compared to the ones of lower elevations.
  71. CO2
    levels are rising as a result of industrial activities, deforestation, and burning and combustion of fossil fuels
  72. CO2
    it is gathered that 45 to 50% remains in the atmosphere. This results in atmospheric imbalance
  73. Role of Trace Gases
    • The amount of these gases is very little as compared with CO2 but they still contribute to a worldwide increase in temperature. These gases include methane
    • (CH4), nitrous oxide (N2O), and certain chlorofluorocarbons (CFC’s). These result in the increases observed in temperatures and result in
    • melting of the ice caps creating an atmospheric imbalance.
Card Set
ch 18 20
ch 18 20