THE TROPOPAUSE - DISCOVERY, DEFINITION AND DEMARCATION

The present paper recounts the discovery of the tropopause and the low er layers of the stratosphere. It provides an overview of studies of t he vertical dimension of the atmosphere prior to the discovery of the stratosphere, and discusses the discovery itself. An account is given of European efforts and the international exchange during this period and this is followed by remarks on its perception during the first dec ade after the discovery. The historical development of terms related t o the tropopause and to the stratosphere is discussed, along with an o utline of various definitions of the tropopause - thermal, dynamical a nd chemical ones - and of the problem related to their use in order to demarcate the tropopause.