While carbon dioxide is a counter-example of global climate change, other greenhouse gases such as methane and nitrous oxide (N2O) are also contributing to global warming. And according to a new study, we release more N2O into the atmosphere than expected, which could undermine our previous efforts to combat climate change.
Like carbon dioxide and methane, N2O emissions are closely related to human industrial activities, especially agriculture. Plants need nitrogen in the soil to grow, so fertilizers rich in this fertilizer have been widely used in the past few decades. But as a by-product, plants release N2O into the surrounding air.
Rona Thompson, lead scientist on the study, said: “The increased use of nitrogen makes it possible to produce more food. But the downside is, of course, the environmental problems associated with it, such as the rise in N2O levels in the atmosphere. “
Once N2O enters the atmosphere, it can cause serious harm. It is far more lethal than carbon dioxide, effectively causing almost 300 times as much damage as carbon dioxide and can deplete the ozone layer. As agriculture develops, N2O is released from the ocean, and as the ocean becomes more acidic, these emission levels will rise.
In view of this background, research teams from the Norwegian Aviation Institute and the University of Maryland have conducted in-depth research on the subject. The team found that N2O levels in the atmosphere have been rising steadily since the mid-20th century, and have been accelerating since 2009. China, India and Brazil contribute the most to global N2O growth.
This means that the atmosphere has much more N2O than previously estimated. The team calculates that Between 2000 and 2005 and 2010 and 2015, N2O accounted for about 10 percent of global greenhouse gas emissions.
Worryingly, this is twice the number reported by the United Nations Framework Convention on Climate Change. The International Panel on Climate Change (IPCC) uses the data in the Convention to develop emission standards. This means that the IPCC does not take these additional N2Os into account.
The team suggested a possible explanation of the difference. As the nitrogen content in the soil steadily increases, a certain amount of nitrogen fertilizer will release more N2O into the air than before. The relationship between this change has never been considered in the past, but an organization like the IPCC assumes that emission factors are constant.
“In Europe and North America, we have succeeded in reducing the growth of nitrous oxide emissions, which is an important factor in climate change and ozone depletion in the stratosphere,” said Eric Davidson, co-author of the study. Unfortunately, in Asia and South America, fertilizer use, intensive livestock farming and the resulting nitrous oxide emissions are growing rapidly. “
The study was published in the journal Nature Climate Change.
Source: University of Maryland, Scimex