-- Shares Facebook Twitter Reddit Email This article was originally published on The Conversation . Food's role in climate change has emerged as one of the defining challenges of our time. The journey of a steak, fruit or salad from the vast expanses of agricultural lands to the plates on our tables leaves a significant footprint on the environment.
At the heart of this challenge is the prodigious use of fertilizers and a growing global population's increasing demand for meat. As earth , climate and atmospheric scientists , we track global greenhouse gas emissions and just published the most comprehensive assessment yet of a powerful greenhouse gas from food production: nitrous oxide, or N2O. After carbon dioxide and methane, N2O is the most consequential greenhouse gas humans are releasing into the atmosphere.
While there is less N2O than carbon dioxide in the atmosphere, it is 300 times more powerful at warming the planet, and it remains in the atmosphere, holding in heat, for over a century. Today, atmospheric N2O levels are about 25% higher than before the Industrial Revolution, and they're still rising at an accelerating rate. N2O's atmospheric concentration was fairly steady until the 1800s, when it began rising quickly.
Measured in Antarctic ice cores (green) and through modern measurements (red). BoM/CSIRO/AAD We found that, globally, fertilizers and the management of livestock manure are leading the increase in N2O emissions and its rapid accumulation in the atmosphe.