Global agriculture and nitrous oxide emissions

TitleGlobal agriculture and nitrous oxide emissions
Publication TypeJournal Article
Year of Publication2012
AuthorsReay, Dave S., Davidson Eric A., Smith Keith A., Smith Pete, Melillo Jerry M., Dentener Frank, and Crutzen Paul J.
JournalNature Climate Change
Pagination410 - 416
Date Published5/2012
Keywordsagriculture, climate, nitrous oxide

Nitrous oxide (N2O) is an important anthropogenic greenhouse gas and agriculture represents its largest source. It is at the heart of debates over the efficacy of biofuels, the climate-forcing impact of population growth, and the extent to which mitigation of non-CO2 emissions can help avoid dangerous climate change. Here we examine some of the major debates surrounding estimation of agricultural N2O sources, and the challenges of projecting and mitigating emissions in coming decades. We find that current flux estimates — using either top-down or bottom-up methods — are reasonably consistent at the global scale, but that a dearth of direct measurements in some areas makes national and sub-national estimates highly uncertain. We also highlight key uncertainties in projected emissions and demonstrate the potential for dietary choice and supply-chain mitigation.