TemperatureInversions

Temperature Inversion

Air Molecules

• As you go higher in the atmosphere, air becomes less dense.

• The air molecules are spaced further apart 1

Air Molecule Density

Air Density

• That is why it is hard to breathe at high altitudes.

• That is also why it is colder at high altitudes

Molecule Density Verses Temperature

Heat is from molecule collisions.

Fewer molecules……

Fewer collisions……

Less heat! 2

Why Air Density Changes

• The weight of the air causes the air at the ground to have high pressure.

• Gravity pulls the air close to the earth

• The high pressure pushes the air molecules close together 3

Air Molecule Density

Temperature vs Pressure• As the pressure of a gas drops, it’s

temperature also drops.

• Evidence– Condensation on a Coleman lantern– Warm soda cools when you open it.

Air Temperature vs Altitude

SO,

The higher you go. . .

The less dense the air . . .

The colder it gets!

Air Temperature

Smoke Rises in the Air,Normally

Why does the hot smoke rise?

4

• What happens to the temperature of the hot smoke as is rises?

5

Temperature Inversion

• A temperature inversion is when a layer of warmer air covers the colder air at ground level.

• http://coep.pharmacy.arizona.edu/air/index.html

6

Temperature Inversion

• It forms when the ground level air is kept cold by the cold ground.

• Then a warm air mass comes from another area and covers the cold air.

• The inversion acts like a lid over the cold ground level air 7-8

How it Happens

Smoke Stops Rising!

Why does the smoke stop rising?

9

All Over Town

The Air Gets Dirty!

Real Dirty!

Temperature Inversion

SO WHAT?

• How do

• temperature inversions

• affect us?

What Can We Do?

What are some ways

we can protect ourselves

from the effects of

temperature inversions?