ESS101C
Prof.
Jin-Yi Yu
Measurements of Ozone
(1) Number Density
Number of
molecules per cubic centimeter (molecules/cm3).
The number density is typically about
5x1012 molecules/cm3 near 20 to
25 km altitude, near the peak of ozone concentration in the stratosphere.
(2) Layer Thickness
The thickness
of pure ozone would have at 1 atm pressure.
One atmosphere-centimeter (1 atm-cm)
is equal to 2.687x1019 molecules/cm2.
One Dobson Unit
(DU) is equivalent to a layer of pure ozone 0.001 cm thick at 1 atm pressure.
A
typical midlatitude ozone column depth is about 300 DU (0.3
atm-cm).
(from WMO Report 2003)