Nitrous oxide, also known as the 'laughing gas' administered by dentists, has the chemical formula N2O. N2O levels have been increasing steadily, with N2O produced when nitrogen-based fertilizers decompose. Another large source of nitrous oxide is the destruction of forests. When forest land is cleared by burning, large amounts of N2O are released. Scientists have also learned that newly cleared forest soil continues to emit large amounts of N2O even after the initial fire, for the next year or so.
N2O levels are increasing about 0.3% per year. Halting the burning of large rainforest areas is one way to slow the increase of this gas, which has an average lifetime in the atmosphere of 150 years. ***