Читать книгу Climate Change For Dummies - Elizabeth May - Страница 56

The amount of nitrous oxide (N₂O) in the atmosphere is even smaller than the amount of methane, but it accounts for about 7 percent of the overall greenhouse effect. The greenhouse effect of nitrous oxide per unit is almost 300 times more potent than that of carbon dioxide. This gas is actually still going up at a rate of 1 part per billion (ppb) each year — as of 2018, it was at 331 parts per billion. Increasingly, nitrous oxide comes from human activities.

The following are ways nitrous oxide appear in the atmosphere:

 In agriculture, farmers encourage those natural bacteria to produce more of the gas through soil cultivation and the use of natural and artificial nitrogen fertilizers. The biggest source of nitrous oxide, natural or human-made, is fertilizers used in agriculture. Fertilizers count for 60 percent of human-made sources and 40 percent of sources overall.

 Ocean- and soil-dwelling bacteria produce nitrous oxide naturally as a waste product.

 Dentists use nitrous oxide as an anesthetic. (Laughing gas is nitrous oxide — not so funny now, is it? Though it’s in such small amounts that you don’t need to worry about your root canal adding to global warming.) Industrial processes (to create nylon, for example) also produce nitrous oxide.

 Humans add a lot of nitrous oxide to the atmosphere by using automobiles. Ironically, cars produce the gas as a side result of solving another environmental problem — see the nearby sidebar for the scoop.