Over the 1970s and 1980s, emissions of carbon dioxide from energy use fell in per capita, per unit GDP, and in some cases in absolute terms in 10 industrialized countries studied by LBNL, These declines were driven principally by falling end-use energy intensities and the decreasing carbon content of energy, By the early 1990s, however, a slowdown in the decline of intensities and the continued growth of GDP and energy services activity have reversed the trends in absolute emissions, LBNL concludes that CO, emissions will continue to rise in the future unless energy intensities and/or the carbon content of energy can be decreased at an accelerated rate via policy changes, technological innovation and/or behavioural adaptation.