Abstract
The probable importance of NO and NO2 in controlling the ozone concentrations and production rates in the stratosphere is pointed out. Observations on and determinations of nitric acid concentrations in the stratosphere by Murcray, Kyle, Murcray and Williams (1968) and Rhine, Tubbs and Dudley Williams (1969) support the high NO and NO2 concentrations indicated by Bates and Hays (1967).Some processes which may lead to production of nitric acid are discussed.The importance of O (1S), possibly produced in the ozone photolysis below 2340 Å, on the ozone photochemistry is mentioned.