Resumen
In order to investigate the volcanic forcing of air temperature on a global scale five different volcanic activity parameter time series are used, two of them representing new modifications of earlier assessments. These parameter time series are compared with each other and with the observed tropospheric (1851-1984) and stratospheric (1964-1984) temperature variations whereby in case of the tropospheric temperature (near suface) 108 regional 'boxes' of seasonal data time series are available. In addition to a correlation analysis, including techniques moving in time, a multiple regression model is used which includes also solar, ENSO and anthropogenic COa forcing. From this model the seasonal and regional maximum air temperature signals are derived which may be due to volcanic forcing. These signals as well as the signal-to-noise ratios are presented in their hemispheric and zonal mean averages and in regional mapping all over the world.