Humidity Flashcards
What is a cloud?
A large collection of very tiny droplets of water and ice crystals. Formed from water vapor, decreased temperature (to dew point temperature), and condensation nuclei (solid surface).
What is air pressure?
A force is exerted on a surface by the air above it as gravity pulls it to earth.
What 3 things are needed for a cloud to form?
Water vapor, decreased temperature (to dew point temperature), condensation nuclei (ash, soot, smoke, etc.)
What is condensation?
The process where water vapor becomes liquid water.
What is dew point temperature?
Temperature air needs to be cooled to in order to achieve a relative humidity of 100%.
What is specific humidity?
The actual amount of water vapor in the air at a given time and place. Expressed as # of grams in water vapor per kg of air.
What is relative humidity?
Percentage of moisture the air actually holds compared to the amount it could hold at a particular temperature. Tells how near the air is to it’s maximum capacity for holding water vapor.
What is relative humidity measured with?
Psychrometer
A psychrometer has two types of bulbs, a _____________________ and a ______________________.
Wet Bulb, Dry Bulb
What is evaporation?
A liquid water to water vapor process that is the source of most atmospheric water vapor. (liquid –> gas)
Condensation is responsible for clouds, dew, and fog. (True or False)
True
Air pressure increases with altitude. (True or False)
False
When humidity increases, air pressure decreases. True or False
True
Air moves from _______________ to __________________.
high pressure to low pressure
Warm air holds more water vapor than cold air. (True or False)
True
