Report Blames Human Activity For Global Warming

LONDON - FEBRUARY 02: An aircraft flies through London skies leaving a vapour trail on February 2, 2007 in London, England. When burning its fuel, planes release exhaust fumes which contain, among others, water vapour and impurities. When these gases come into contact with the cold air, the significant temperature difference causes the water on the impurities to condense and turn to ice. Aircraft exhaust fumes have been attributed to climate change. (Photo by Daniel Berehulak/Getty Images)