Barometers

Created by Laura Glantzberg for

Barometer Basics• Barometers measure atmospheric pressure, also

known as barometric pressure– This means it measures the amount of pressure exerted by

the weight of air over a given area– Air pressure creates changes that produce the winds that

bring in clouds, or clear the way for sunny skies

• Barometers are very important for forecasting weather

Reading a Barometer

• Barometers typically have 2 types of readings:– inches- this

refers to “inches of mercury”

– Millibars (mb) or hectopascals (hPa)-the measurement used by meteorolgist

Adjusting Barometers

• Barometers read differently based on the elevation

• In order to get proper readings, the barometer must be adjusted according to elevation

High vs. Low Pressure• Average sea level pressure is

1013 millibars– Anything below this pressure is

considered low pressure• Pressure in this area is below its

surrounding environment • The formation of a low-pressure

area is called cyclogenesis.– Anything above this pressure is

considered high pressure• Pressure in this area is above its

surrounding environment so the air will move outward to areas of less dense pressure

Practice Makes Perfect!

• Break into groups and practice reading different barometers

• Write down the reading of each barometer.