As efforts to mitigate climate change increase, there is a need
to identify cost-effective ways to avoid emissions of greenhouse
gases (GHGs). Agriculture is rightly recognized as a source of
considerable emissions, with concomitant opportunities for
mitigation. Although future agricultural productivity is
critical, as it will shape emissions from conversion of native
landscapes to food and biofuel crops, investment in agricultural
research is rarely mentioned as a mitigation strategy. Here we
estimate the net effect on GHG emissions of historical
agricultural intensification between 1961 and 2005. We find that
while emissions from factors such as fertilizer production and
application have increased, the net effect of higher yields has
avoided emissions of up to 161 gigatons of carbon (GtC) (590
GtCO2e) since 1961. We estimate that each dollar invested in
agricultural yields has resulted in 68 fewer kgC (249 kgCO2e)
emissions relative to 1961 technology ($14.74/tC, or ~$4/tCO2e),
avoiding 3.6 GtC (13.1 GtCO2e