428 Table 142 



ABSORPTION OF RADIATION BY OZONE 



Parts A and B of this table give values of the "decimal" absorption coefficient of ozone, 

 3) in the ultraviolet and in the visible bands as determined in the laboratory by Ny and 

 Choong * and by Colange 2 respectively. The average absorption coefficient for narrow 

 wave-length intervals has been taken from curves in the references cited. The pressure 

 dependence is small for these bands. 3 ' * Evidence indicates a temperature effect on the 

 absorption coefficients in the ultraviolet bands, 5, 8 ' 7 but there is conflicting evidence con- 

 cerning a possible temperature effect in the visible band. 8, 9 ' 10 



The "decimal" absorption coefficient a and the "Naperian" absorption coefficient k are 

 defined by the following expressions 



h = hx \0- ax = hxe- k ' 



where /ox is the initial intensity of a parallel beam of radiation of wave length in the 

 neighborhood of X and h is the intensity after passing through a layer of ozone x centi- 

 meters thick at normal pressure and temperature (0 °C. and 760 mm. Hg.) ; e is the 

 base of the natural logarithms. Values of a are tabulated, and corresponding values of 

 k may be obtained from the relationship 



k = a log 10 = 2.3026 a. 



Part C gives the percentage absorption by ozone under laboratory conditions for a 

 path of ozone 1 centimeter long at °C. and 760 mm. Hg. as given by Sutherland and 

 Callendar. u Strong * states that the absorption by ozone in the infrared is proportional 

 to the fourth root of the total pressure. 



> Ny Tsi-Ze and Choong Shin-Piaw, Chinese Journ. Phys., vol. 1, p. 38, 1933. 

 a Colange, G., Journ. d. Physique, vol. 8, p. 254, 1927. 



3 Vassy, E., Conference on atmospheric ozone held at Oxford, Sept. 9-11, 1936, p. 26, published by 

 the Royal Meteorological Society, London, 1936. 



I Strong, J., Journ. Franklin Inst., vol. 231, p. 121, 1941. 



5 Wulf, O. R., and Melvin, E. H., Phys. Rev., vol. 38, p. 330, 1931. 



6 Vassy, E., Ann. Phys., vol. 8, p. 679, 1937. 



7 Gotz, F. W. P., Beitr. Geophys., Ergebnisse der Kosmischen Physik, vol. 3, p. 253, 1938. 



8 Humphrey, G. L., and Badger, R. M., Journ. Chem. Phys., vol. 15, p. 794, 1947. 

 »Vigroux, E., Compte Rend., vol. 227, p. 272, 1948. 



10 Vassy, A., and Vassy, E., Journ. Chem. Phys., vol. 16, p. 1163, 1948. 



II Sutherland, G. B. B. M., and Callendar, G. S., Reports on progress in physics, vol. IX, The 

 Physical Review, London, 1943. 



{continued) 



SMITHSONIAN METEOROLOGICAL TABLES 



