Dobson unit in atmospheric chemistry

https://dx.doi.org/10.1351/goldbook.D01827
Unit sometimes used in the description of the total ozone in a column of air overhead. It is given as the thickness (in units of 10 −3 cm or 10 −5 m) of that layer which would be formed by the total ozone in a column reduced to the pressure of 760 Torr and temperature of 0 °C.
Source:
PAC, 1990, 62, 2167 (Glossary of atmospheric chemistry terms (Recommendations 1990)) on page 2185