Abstract
Because of its relative insensitivity to changes of station location and to such natural phenomena as volcanic activity, precipitation is a promising weather element for the study of secular changes of the general circulation. A study of the precipitation records for individual stations, smoothed by the use of decadal moving averages, suggests that the prominent precipitation trends are continuous in time and space. A preliminary synoptic study of the interdecadal changes of average precipitation reveals details of the circulation changes in regard to cyclonic activity and moisture supply.
