Air Pressure, Forces, and Motion Meteorology 101 Dr. Robert M MacKay

Pressure Temperature Volume The Gas Law P=C*density*Temp P=2.87 T

Gas Laws

Constant P as T increases V Increases/decreases Constant V as T increases P Increases/decreases Constant T as V increases P Increases/decreases Constant V,T as M increases P Increases/decreases

Gas Laws Constant P as T increases V Increases/decreases Constant V as T increases P Increases/decreases Constant T as V increases P Increases/decreases Constant V,T as M increases P Increases/decreases

Mercury Barometer Pressure Measurement 1013 mb = 1013 hPa Millibar hectoPascal 1013 mb in Hg 76 cm Hg 760 mm Hg 760 Torr 14.7 psi

Station Pressure + Elevation(meter)/10 = Sea Level Pressure

Newtons Laws of Motion Newtons 3 laws of motion 1. Law of inertia 2. Net Force = mass x acceleration ( F = M A ) 3. Action Reaction

1st Law (Law of Inertia) Every object continues in its state of rest, or of uniform motion in a straight line, unless it is compelled to change that state by forces impressed upon it. acceleration = 0.0 unless the objected is acted on by an unbalanced force

1st Law Inertia (The intrinsic tendency of an object to rest changes in motion) Mass is a measure of an objects inertia Mass is also a measure of the amount of an objects matter content. (i.e. protons, neutrons, and electrons)

Newtons 2nd Law Net Force = Mass x Acceleration F = M A

Newtons Law of Action Reaction (3rd Law) You can not touch without being touched For every action force there is and equal and oppositely directed reaction force

Forces that influence the wind 1. Pressure Gradient Force 2. Coriolis Force 4. Friction On average gravity nearly balances the vertical Pressure gradient (hydrostatic balance)

Pressure Gradient=P/dist

Pressure Gradient

Centrifugal force an (Apparent Force)

Coriolis Force (apparent force due to Earths rotation)

Coriolis Force