This volume addresses a number of both experimental techniques and methods for the data treatment introduced in the last ten years or so in different fields of the atmospheric sciences. Considerable emphasis has been given since their introduction to the use of satellites or spaceborne measurements with a recent example being the important results obtained with UARS. Of particular interest are the airborne instruments developed for the stratospheric measurement campaign organized by the NASA since 1976 to study the ozone hole and followed later by similar experiments to study the high-latitude ozone depletion in the northern hemisphere. The results of these experiments have helped clarify the role of chlorine-bearing compounds in the ozone depletion and the effect of the heterogeneous processes. The book is organized in four chapters: the first three divide the different techniques according to the location of the measuring instrumentation (ground, air and space) with the fourth chapter dealing with theory and analysis.