1. Saturated (cloudy) air at a temperature of 20 °C (68 °F) has a relative humidity of _________%.
2. Compute the relative humidity (RH) to nearest percent for each of the following atmospheric conditions:
a. vapor pressure = 6 mb, saturation vapor pressure = 18 mb, RH = __________ %
b. mixing ratio = 4.5 g/kg, saturation mixing ratio = 9.0 g/kg, RH = __________ %
c. mixing ratio = 12.0 g/kg, saturation mixing ratio = 12.0 g/kg, RH = __________ %
3. Outdoors, the air temperature is 5 °C (44 °F) and the relative humidity is 70%. What is the relative humidity of the air if it is drawn indoors and heated to 20 °C (68 °F)? Assume that no water vapor is added to or removed from the air. (This is the situation with heating homes in the winter season.)
Answer: _______%
4. If the relative humidity is 68% and the vapor pressure is 16 mb, what is the vapor pressure at
saturation?
Answer: _________ mb
What is the approximate saturation air temperature? Answer: _________ °C.
5. On a clear and calm day, the air temperature at sunrise is 5 °C (41 °F) with a relative humidity of 90%. The air temperature reaches a maximum of 15 °C (59 °F) at 3 p.m. Assuming that no water vapor is added to or removed from the air, predict the value of the relative humidity at 3 p.m.
Answer: _____ %
3 answers
2a.33
2b.50
2c.100
3.60
4a.24
4b.12
5.46
1.) 100%
2.) a. 25%
b. 33%
c. 100%
3.) 17%
4.) a. 24mb
b. 20
5.) 42%