Lead Author:
Peter J. Marcotullio, Hunter College, City University of New York
Contributing Authors:
Lori Bruhwiler, NOAA Earth System Research Laboratory
Steven Davis, University of California, Irvine
Jill Engel-Cox, National Renewable Energy Laboratory
John Field, Colorado State University
Conor Gately, Boston University
Kevin Robert Gurney, Northern Arizona University
Daniel M. Kammen, University of California, Berkeley
Emily McGlynn, University of California, Davis
James McMahon, Better Climate Research and Policy Analysis
William R. Morrow, III, Lawrence Berkeley National Laboratory
Ilissa B. Ocko, Environmental Defense Fund
Ralph Torrie, Canadian Energy Systems Analysis and Research Initiative
Expert Reviewer:
Sam Baldwin, DOE Office of Energy Efficiency and Renewable Energy
Science Lead:
Paty Romero-Lankao, National Center for Atmospheric Research (currently at National Renewable Energy Laboratory)
Review Editor:
Emily J. Pindilli, U.S. Geological Survey
Federal Liaison:
Nancy Cavallaro, USDA National Institute of Food and Agriculture

Energy Systems

North America’s annual share of global CO2e emissions reached its first peak during the 1920s, when the share ranged from 50% to 58% of total emissions, which at that time were 490 to 550 Tg C (1.8 to 2.0 Pg CO2e). By 1945, global emissions levels reached 672 Tg C (2.5 Pg CO2e) per year, at which point North America accounted for about 59% of total annual emissions.11

Thereafter, North America’s annual share started a monotonic decline that, by 2008 despite reaching an absolute regional high of 1,830 Tg C (6.6 Pg CO2e), was less than 21% of the total annual global emissions. By 2013, the North American annual share of total global emissions was down to 17%. The cumulative share from North America has been steadily falling since the late 1950s, when it was about 43%, to 2013 when it stood at around 29% (see Figure 3.9). The declining annual and cumulative shares of North American energy-related CO2e emissions demonstrate the growing influence of fossil fuel combustion in emerging economies.


Figure 3.9: Change in Cumulative Share of Carbon Dioxide Emissions from Fossil Fuel Burning, Cement Manufacture, and Gas Flaring

Figure 3.9: Percentages are by region, from 1751 to 2013. [Data source: Boden et al., 2016.]