A5-9. Natural light is received from the sun and electric lamps, fire, or fluorescent tubes
produce artificial light.
A5-10. Reflection occurs when light waves that are neither transmitted nor absorbed,
but are thrown back from the surface of the medium they encounter. Refraction
occurs when a ray of light passes at an oblique angle from one transparent
substance into another substance of different density.
A5-11. Mirages are images of objects that are made to appear displaced from their
normal positions because of refraction.
A5-12. The diameter range of a mature thunderstorm cell is 1 to 6 miles.
A5-13. Rain is observed at the surface during the mature stage.
A5-14. A macroburst is a larger scale downburst with winds that can last 5 to 20 minutes
with speeds that reach 130 knots. Microbursts are smaller scale downbursts with
winds that last 2 to 5 minutes with speeds that may reach 130 knots.
A5-15. Two types of thunderstorms are air mass and frontal.
CHAPTER 6
A6-1. Climate is the average or collective state of Earth's atmosphere at any given
location or area over a long period of time.
A6-2. Descriptive climatology is typically oriented in terms of geographic regions.
A6-3. Microclimatology is measured in small-scale areas such as golf courses or
plowed fields.
A6-4. The most important climatic element is temperature.
A6-5. Wind is the climatic element that transports heat and moisture into a region.
A6-6. The mean or average is the climatological parameter that is determined by
adding all values together and dividing by the number of values calculated.
A6-7. Absolute is the term that is usually applied to the extreme highest or lowest value
ever recorded at a location.
A6-8. A degree day is the number of degrees the mean daily temperature is above or
below a standard temperature base.
A6-9. The climatic belts or zones are the torrid or tropical zone, the two temperate
zones, and the two polar zones.
A6-10. The three climatic classification types are C.W. Thornthwaite, W. Köppen, and
G.T. Trewartha.
A6-11. The five climatic types according to Köppen are tropical rain, dry, warm
temperate rainy, cool snow forest (Boreal), and polar.
A6-12. Latitude is the climatic control that has the biggest effect on climatic elements.
A6-13. Coastal areas assume the temperature characteristics of the land or water that is
on their windward side. Therefore, in the middle latitudes, the western coast of
the United States will normally receive maritime temperature characteristics
from the Pacific Ocean, and the eastern coast will normally receive continental
temperature characteristics from the mainland.
A6-14. Ocean currents transport heat by moving cold polar water equatorward into
warmer waters and moving warm equatorial water poleward into cooler waters.
AII-5