Arctic Yearbook 2015 - Page 89

89 Arctic Yearbook 2015 estimated to be the second most important greenhouse gas (GHG) emitted by human activities after CO2,” though the Report does acknowledge the study’s then-recent findings. Another scientific assessment that chronicled BC dating established that by the 1890s biofuel produced from open burning was the leading cause of BC emissions, followed by coal emissions from the 1880s to the 1950s, with the addition of diesel and return of biofuel by the latter half of the 20th century (Bond et al. 2007). At present, diesel engines and traditional biofuel account for 90% of BC emissions, with the addition of gas flaring which is associated with significant emissio