Umkehr method

Reinsel G., Tiao G.C., Lewis R. and Bobkoski M., Analysis of upper stratospheric ozone profile data from the ground-based umkehr method and the Nimbus-4 BUV satellite experiment. J. Geophys. Res. , 88, 5393-5402 (1983). 

This procedure is called the Umkehr method (Gotz, 1951). 

The vertical distribution of ozone is derived by the Umkehr method. Direct solar intensity is measured at two different wavelengths, one being more absorbed by ozone than the other. At sunrise and sunset, the intensities decrease at different rates. The ratio shows an inversion. This is called the Umkehreffekt and gives information about the vertical distribution of ozone in the atmosphere. An Umkehr measurement takes about three hours, and provides data up to an altitude of 48 km, with the most accurate information for altitudes above 30 km. 

Die in der Zuckerchemie iibliche Methode der Substitution einer Mesyloxy-Gruppe unter Waldenscher Umkehr wurde zur Darstellung der 2-Amino-2-desoxy-l,6-anhydro-p-D-gulopyranose aus dem 3-mesylierten Derivat der 2-Acetamido-2-desoxy-l,6-anhydro-p-D-galactopyranose aus-gentitzt... 

The use of rockets offers a unique opportunity for the penetration of the entire ozone layer in contrast to the partial penetration afforded by balloons. Except for the meager data obtained by the Umkehr effect 17, 56) and from calculations based on the pressure-sensitive infrared absorption of ozone 12, 55), no absolute data on the vertical distribution of ozone have been obtainable (before the use of rockets) to altitudes above about 32 km. Little credence could be given to data obtained by either the Umkehr effect or to the infrared method for altitudes above about 40 to 50 km., as both methods are indirect and require appreciable optical absorption to permit practical application. 

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