Why laughing gas is a growing climate problem

Nitrous oxide, also known as "laughing gas," is the most important greenhouse gas after methane and carbon dioxide and the biggest human-related threat to the ozone layer. Stanford scientist Rob Jackson explains why emissions of the gas are rising faster than expected and what it will take to reverse the trend. Carbon dioxide and methane are the biggest drivers of global warming related to human activities. But emissions of nitrous oxide, better known as laughing gas, are also rapidly increasing, mostly due to large-scale farming with synthetic fertilizers and cattle ranching. Nitrous oxide emissions are rising fastest in emerging economies where both crop production and livestock numbers are increasing. (Image credit: iStock) Nitrous oxide emissions from human activities have ballooned 30 percent over the past four decades, barreling past the highest emission levels scientists have projected in climate models, according to new estimates published Oct. 7 in the journal Nature.