Summary
Measurements of global solar relation was performed during a whole year period (1976-1977) in the Solarimetric Station of INPA in Manaus (AM). A method to estimate the maximum possible solar radiation (for bright sunshine periods) in a daily basis in introduced and tested. The estimated values showed errors less than 7% if compared to measured values. An estimation of the mean annual maximum atmospheric transmission which showed to be 81% of the incident extraterrestrial solar radiation.