Аннотация:The results of the interferometric data processing of Canadian Radarsat-2 spaceborne synthetic aperture radar (SAR) acquired over Tolbachik volcanic complex in summer-fall 2013 are discussed. The phase difference deviations being revealed on the interferograms may be removed in some cases using the phase screen information generated using the weather stations archival meteorological records. The corruptions caused by cloud layers' heterogeneities, variations of air refraction coefficient height profiles, and fast variations of atmosphere conditions during dusk/down are the most complicating factors because of the lack of detailed description of clouds spatial structure and atmosphere parameters. One of most unexpected effects is atmosphere heterogeneity because of mixture of illuminated and shaded areas in mountainous regions in the case of interferometric SAR observations during dusk.