Accession Number : AD0294134

Title :   NACREOUS CLOUDS

Corporate Author : LIBRARY OF CONGRESS WASHINGTON D C AEROSPACE TECHNOLOGY DIV

Report Date : 14 JAN 1963

Pagination or Media Count : 1

Abstract : Nacreous clouds are one of the most rarely occurring forms of clouds; during the entire history of the physics of the atmosphere they have probably been observed no more than a hundred times. Notwithstanding, nacreous clouds are of extreme interest for the study of the stratosphere. hey give an idea of the watervapor content and condensation phenomena, and also of the velocity and form of motion of theAIR AT ALTITUDES OF 21 TO 30 KM. Nacreous clouds are very thin and transparent; they are observed by day as well as at dusk at an altitude of 21 to 30 km, i.e., much higher than the usual clouds of the troposphere. Bright iridescences of color are visible in nacreous clouds, and it is from these iridescences that the clouds derived their name. As to form, they are similar to lens-shaped clouds (Altocumulus lenticularis), and they show clear traces of a wavelike structure. In shape and color they differ substantially from noctilucent clouds, which are observed at heights of more than 75 km. (Author)

Descriptors :   *CLOUDS, *METEOROLOGY, TRANSLATIONS

Distribution Statement : APPROVED FOR PUBLIC RELEASE