The Analysis of Monthly moisture advection changes in Iran's atmosphere over the recent half-century

The purpose of this study is to investigate the changes of temporal and spatial moisture advection in Irans atmosphere. To achieve this purpose, data -orientation and meridional components of the database during the 1390-1340 NCEP / NCAR related to the Oceanography Organization United States was extracted, examined and analyzed .For the calculation of features and software programming environment Mat lab, software Grads and Surfer software was used to perform graphics operations’. The largest decline occurred in summer. However, in all months, western and southern parts of zagros had the most intensive decreasing slope during the period. In all months, especially summer, south east have increasing consistency.