Pressure

stormy weather

• High Pressure System
• Low Pressure System

clear skies

• High Pressure
• Low Pressure

cloudy skies

• High Pressure System
• Low Pressure System

thunder, lightning, and heavy rain

• High Pressure System
• Low Pressure System

sunny skies

• High Pressure System
• Low Pressure System

A _____________ is the scientific  instrument used to measure air pressure.

• barometer
• thermometer
• mercury
• watch

As you climb up a mountain what happens to the air pressure?

• decreases
• increases
• stays the same

What happens to the amount of oxygen molecules as altitude increases?

• fewer molecules
• more molecules
• same amount of molecules
• nothing happens to the molecules

What causes winds?

• differences in precipitation
• differences in humidity
• differences in air pressure

What does a barometer measure?

• Temperature

• Density

• Pressure