The relative humidity tells what percentage of the maximum amount of water is in the air. Since air is colder at higher altitudes and nearer the north and south poles, air masses do get cooled. If this air is cooled to 22 C, the hits by gas phase water molecules on a standard area cause a condensation rate equal to the larger evaporation rate of 37 C. Liquid water at the new temperature of 22 C does not have as large an evaporation rate, and until the pressure of water vapor gets down to the 22 C maximum of 0.026 atm, the condensation rate is going to be larger than the evaporation rate. This means that liquid water is going to form on any surface touched by the cooled air. If that surface is the ground, the liquid water that forms is called dew.
People use the evaporation of water to get rid of heat.
The rest ends up as molecular motion, which must be transferred to the surroundings to avoid raising body temperature. The energy transfer is done by using energy from collisions among water molecules to break some of them free from the hydrogen bonds that keep them together in liquid water. Read Sec 24.1 1. Be able to apply the vapor pressure situations for ocean water and clouds to Fig 24.2. Read Sec 25.2 2.