Pressure-Temperature-Density
¥Pressure
¥Higher along horizontal red line in warm air than in cold air
¥Pressure difference is a non-zero force
¥Pressure Gradient Force or PGF (red arrow)
¥Air will accelerate from column 2 towards 1
¥Pressure falls at bottom of column 2, rises at 1
Text Box: 8.5 km COLDText Box: 9.5 km WARMText Box: 300 mbText Box: 1000 mbText Box: 400 mbText Box: 500 mbText Box: 600 mbText Box: 700 mbText Box: 800 mbText Box: 900 mb
H
L
L
H
PGF
Text Box: 200 mbText Box: 100 mb