Nitrous oxide is another potent greenhouse gas generated by agriculture, industrial activity, and waste. N2O has 300 times the greenhouse power of CO2 and lingers in the air for 120 years. In reaction with oxygen, N2O gives rise to nitric oxide (NO), which in turn reacts with ozone to break it down. Though there is scant nitrous oxide in the air, its contribution to global warming is considerable: 10%.
Over 1/3rd of N2O emissions are man-made. The countries with the greatest nitrous oxide output are China, Brazil, and the United States.