in response Response to the controversy Communication , the american association for the advancement of science ( aaas ) , the american meteorological society ( ams ) and the union of concerned scientists ( ucs ) released Statement statements Statement supporting Supporting the scientific consensus that the earth 's mean surface temperature had been rising Cause_change_of_position_on_a_scale for decades , with the aaas concluding Coming_to_believe : `` based on multiple lines of scientific evidence that global climate change Change caused Causation by human activities is now underway ... it is a growing Expansion threat to society '' .