Carbon dioxide is the most well-known of greenhouse gases. But there are others deserving of their own spotlight. Nitrous oxide is one of them. It turns out that the same “laughing gas” once used by dentists as an anesthetic is pretty bad for the environment. In fact, it’s more than 300 times more potent as a greenhouse gas than carbon dioxide, and it can remain in the atmosphere for more than 100 years.
According to a new study by a team of international scientists, rising nitrous oxide emissions around the world are jeopardizing the climate goals of the Paris Agreement. The growing use of nitrogen fertilizers in global food production is increasing atmospheric concentrations of nitrous oxide.
The study, which was led by Auburn University and recently published in the journal Nature, finds that nitrous oxide emissions are increasing faster than any emission scenario developed by the Intergovernmental Panel on Climate Change. The current trajectory would lead to global mean temperature increases well above 3°C from pre-industrial levels. The Paris Agreement aims to limit global warming to less than 2°C.
According to the study, nitrous oxide levels have risen 20% from pre-industrial levels, with the fastest growth observed in the last 50 years due to emissions from human activities. The largest contributors to nitrous oxide emissions come from East Asia, South Asia, South America, and Africa. The United States, China, and India dominate nitrous oxide emissions from synthetic fertilizers, while Africa and South America dominate releases of nitrous oxide from natural sources, like livestock manure.
Nitrous oxide emissions pose an increasing threat to the climate.
Photo, posted April 22, 2012, courtesy of Bill Meier via Flickr.