Air Pressure and Wind Pressure Volume Temperature If

Air Pressure and Wind

Pressure, Volume, Temperature ● If you increase pressure, what happens to Volume and Temperature? ● If you increase temperature, what happens to Volume and Pressure? ●Write a few sentences in your journal to explain two ways that pressure, temperature and volume are linked when talking about weather changes.

Air Pressure – “rules” ● Air pressure is exerted in all directions – up, down, sideways. ● The pressure balances in all directions equally. ●refer to can crushing demo; hot air balloon image in note packet ● Standard sea level measurement is 1013. 2 millibars = 29. 92 inches of mercury

Air pressure and weather ● Compare sea level readings to what our weather journals have indicated. ● What weather should we expect to see when barometric pressure decreases? ● What weather conditions would you predict when barometric pressure increases? ● Those are the Low and high pressure systems referred to on weather forecasts ● Where does temperature come into play then?

How are the Pressure gradients related to wind? the closer the gradients __________.

How is temperature related to wind?

What is the Low pressure in the Atlantic ocean?

How do winds blow around Pressure systems? ● Low pressure = “cyclone”, pressure decreases as you travel more toward the center – flow is counterclockwise ● High pressure “anti-cyclone” – pressure increases as you travel toward the center – flow is clockwise ● Rotation is due to change of pressure and Coriolis effect (more on this soon) ● Right/ left hand demo

Sketch this in your journal

Wind - cause and result ● The unequal heating of the earth’s surface creates differences in temperature, which leads to differences in pressure. ● Air flows from high pressure to areas of low pressure (this is diffusion – it happens with all molecules and matter, it is what we saw in the convection lab) ● Wind is the result of horizontals differences in air pressure. ● Solar energy is the ultimate energy source for most wind!

3 -D high and low pressure meet Sketch this

Summarize ● Please write 5 summary sentences, include the following: ● how is wind “created” ● What is the difference between high and low pressure systems in their motion ● What does barometric tell us in a weather report ● What kind of weather is associated with high and low pressure systems

Factors affecting Wind ● 1. pressure differences ( caused by? ) ● 2. Coriolis effect ( caused by? ) ● 3. Friction ( between air molecules and earth’s surface features) ● Pressure differences – the greater the differences the greater the wind speed

Wind symbols

Measuring Air Pressure ● A student of Galileo, invented a mercury Barometer – as air pressure in the tube increases, mercury rises in tube; as air pressure decreases, the column of mercury does also. ● Our weather data measure Barometric pressure in inches, this relates back to the original measurement system.