The Water Cycle Evaporation Sun heats water Liquid water changes to gas (vapor) Watervaporrises with warm air
Humidity Amount of water vapor, or moisture in the air Changes with temperature Warm air holds more moisture than cold air Cold Air Warm Air
Measuring Humidity Hygrometer is used to measure the amount of water vapor in the air.
The Water Cycle Condensation Water vapor cools Tiny water droplets or ice crystals form Get bigger and heavier
The Water Cycle Precipitation Air can’t hold up heavy water droplets or ice crystals They begin to fall
The Water Cycle All the different forms of water that fall from the sky.
Precipitation The air temperature determines the form of precipitation.
Types of Precipitation Rain Liquid Air temperature above 32 degrees Fahrenheit Snow Solid Air temperature below 32 degrees Fahrenheit Hail Solid Formed in clouds Winds carry frozen drops higher Layers of ice are added Repeats Sleet Mixture Air temperature just above freezing
Measuring Precipitation Rain gauge Open container that collects precipitation Scale on side of container shows how much has fallen
The Water Cycle Runoff Water that does not soak into the ground Runs downhill into puddles, streams, rivers, or lakes Then the whole cycle begins again