Solution: Ozone layer thickness is expressed in terms of dobson units which is measure what is physical thickness would be if compressed in earth atmosphere. 1 Dobson unit is defined to be 0.01 mm thickness at STP (standard temperature and pressure) . The unit is named after G,M.B Dobson ,one of the first scientist to investigate atmospheric ozone.1 Dobson is equal to 2.687*10∧20 molecules of ozone per square metre.
