The Water Cycle BrainPop

What is the water cycle? The continuous movement of water from water sources into the air, onto and over land, into the ground, and back to the water sources.

6 steps Precipitation Infiltration Runoff Transpiration Evaporation Condensation

Precipitation Occurs when rain, snow, sleet, or hail falls from the clouds onto the Earth’s surface. It is the primary connection in the water cycle that provides for the delivery of atmospheric water to the Earth. Most precipitation falls as rain.

Infiltration The downward movement of water from the land surface onto soil or porous rock. Water can be filtered and cleaned as it passes through the soil or rock.

Runoff Is water, usually from precipitation, that flows across land and collects in rivers, streams, and eventually the ocean.

Transpiration The process by which plants release water vapor into the air through their leaves. Transpiration accounts for approximately 10% of all evaporating water.

Evaporation Occurs when liquid water changes into water vapor. Approximately 80% of all evaporation is from the oceans. Evaporation is more intense in the presence of warmer temperatures.

Condensation Occurs when water vapor cools and changes back into liquid droplets. This is how clouds form. Water vapor needs a place to condense on. Grass A glass

Dew Point The dew point is the temperature to which air must cool to be completely saturated.

Relative Humidity Humidity: is the amount of water vapor or moisture in the air. Relative Humidity: is the amount of moisture the air contains compared with the maximum amount it can hold at a particular temperature. When air holds all of the water it can at a given temperature it is said to be saturated. The higher temperature, the more water the air can hold.

Relative Humidity How to calculate relative humidity: Actual water in the air x 100 = relative humidity Saturated air (full) Suppose that 1 m³ of air at a certain temperature can hold 24 g of water vapor. However, you know that the air actually contains 18 g of water vapor. Calculate the relative humidity. Example: 18 g/m³ x 100 = 75% 24 g/m³