1. During the course of a year the sun will disappear from view at the North Pole on what date?

     a.  June 21

     b.  September 23

     c.  December 23

     d.  January 1

     e.  March 21


 2. Which of the following is correct at the time of the summer solstice in June?

     a.  it marks the beginning of astronomical summer in the Northern Hemisphere

     b.  it occurs around June 22

     c.  the noon sun is overhead at the Tropic of Cancer

     d.  all of the above


3. Between Christmas and New Year's, at middle latitudes in the Northern Hemisphere, the length of the day:

     a.  increases

     b.  decreases

     c.  does not change

     d.  is 12 hours long


4. Although the polar regions radiate away more heat energy than they receive by insolation in the course of a year, they are prevented from becoming progressively colder each year by the:

     a.  conduction of heat through the interior of the earth

     b.  concentration of earth's magnetic field lines at the poles

     c.  circulation of heat by the atmosphere and oceans

     d.  the insulating properties of snow

     e.  release of latent heat to the atmosphere when polar ice melts


5. During the afternoon the greatest temperature difference between the surface air and the air several meters above occurs on a:

     a.  clear, calm afternoon

     b.  clear, windy afternoon

     c.  cloudy, calm afternoon

     d.  cloudy, windy afternoon


6. Assuming that the night will remain clear, calm, and unsaturated, the predicted minimum temperature is 32 F. Suddenly the wind speed increases and remains gusty throughout the night. The minimum temperature will most likely be:

     a.  about the same as predicted, but will occur earlier in the night

     b.  higher than predicted due to the release of latent heat

     c.  much lower than predicted due to radiational cooling

     d.  higher than predicted due to mixing


 7. At what time during a 24-hour day would a radiation temperature inversion best be developed?

     a.  at sunset

     b.  near sunrise

     c.  toward the end of the morning

     d.  between 2 and 5 pm when the air temperature reaches a maximum


8. In a hilly region the best place to plant crops that are sensitive to low temperatures is:

     a.  on the valley floor

     b.  along the hillsides

     c.  on the top of the highest hill

     d.  in any dry location


9. Over the earth as a whole, one would expect to observe the smallest variation in temperature from day to day and from month to month:

     a.  at the North Pole

     b.  in the center of a large land mass

     c.  along the Pacific coast of North America

     d.  high in the mountains in the middle of a continent

     e.  on a small island near the equator


 10. The wind-chill factor:

     a.  relates body heat loss with wind to an equivalent temperature with no wind

     b.  indicates the temperature at which water freezes on exposed skin

     c.  takes into account humidity and air temperature in expressing the current air temperature

     d.  tells farmers when to protect crops from a freeze

     e.  determines how low the air temperature will be on any given day