Stratospheric Water Vapour Increase due to Human Activities

GREAT interest has been aroused by the possibility that a fleet of supersonic transports (SST) flying in the stratosphere would deposit sufficient water vapour to increase the average global concentration by about 7%, from 3 p.p.m. to 3.2 p.p.m. (ref. 1). The injection of this water vapour would result in a small decrease in stratospheric temperature according to Manabe and Wetherald^2,3. Perhaps more significantly, it could decrease the concentration of ozone in the lower stratosphere through a series of photochemical reactions^4-9.