| A | B |
|---|
| air pressure | the amount that air presses or pushes on anything |
| low-pressure area | a place where warm air rises and pushes down on the earth's surface with less pressure |
| high-pressure area | a place where cool air sinks and pushes down on the earth's surface with more pressure |
| barometer | a tool that measures air pressure |
| humidity | the amount of water vapor in the air |
| temperature | the measure of heat in the air |
| thermometer | an instrument to measure air temperature |
| evaporation | liquid water heats, turning into water vapor |
| condensation | water droplets form when warm air is cooled |
| precipitation | moisture that falls from clouds to the ground |
| runoff | water that doesn't soak into the earth, runs downhill |
| wind | moving air |
| anemometer | a tool that measures the speed of wind |
| rain gauge | a tool that measures precipitation |
| wind vane | a tool that measures the direction of the wind |
| water vapor | the amount of water in the air |
