QT6: On a clear, calm morning, water condenses on the ground in a thick
layer of dew. As the water slowly evaporates into the air, you measure a
slow increase in dew point. Explain why.
PE1: On a bitter cold, snowy morning, the air temperature and dew point
of the outside air are -7oC. If this air is brought indoors and
warmed to 21oC, with no change in vapor content, what is the
relative humidity of the air inside the home? (Hint: See Table 1, p. 98 and
the formula on the same page.)
PE2: (a) With the aid of Fig. 4.13b, p. 94,
determine the average July dew points in St. Louis, MO; New Orleans, LA;
and Los Angeles, CA. (b) If the high temperature on a particular summer day
in all three cities is 32oC (90oF), then calculate the
afternoon relative humidity at each of the three cities. (Hint: Either Fig.
4.10, p. 91 or Table 1, p. 98, will be helpful.)
QT2: Explain why icebergs are frequently surrounded by fog.
QT4: While driving from cold air (well below freezing) into much warmer
air (well above freezing), frost forms on the windshield of the car. Does
the frost form on the inside or outside of the windshield? How can the
frost form when the air is so warm?
QT10: Near the shore of an extremely large lake, explain why steam fog
is more likely to form during the autumn and advection fog in early spring.
PE1: The data in the chart below represent the dew-point temperature
and expected minimum temperature near the ground for various clear winter
mornings in a southeastern city. Assume that the dew point remains constant
throughout the night. Answer the following questions about the data. (a)
On which morning would there be the greatest likelihood of observing visible
frost? Explain why. (b) On which morning would frozen dew most likely
form? Explain why. (c) On which morning would there be black frost with no
sign of visible frost, dew, or frozen dew? Explain. (d) On which morning
would you probably only observe dew on the ground? Explain why.