“Surprising Study Finds Nitrogen Emissions Have Cooling Effect on Climate, But Urgent Action Needed to Combat Global Warming”

The study conducted by an international team of researchers, led by the Max Planck Institute in Germany and including authors from the University of Sydney, has shed light on the complex relationship between nitrogen emissions and climate change. Published in Nature, the paper reveals that while nitrogen emissions from fertilisers and fossil fuels have a net cooling effect on the climate, increasing atmospheric nitrogen poses further damaging effects on the environment.

According to the research, reactive nitrogen released into the environment through human activities cools the climate by minus 0.34 watts per square metre. This cooling effect is attributed to various factors, including the formation of fine suspended particles that shield sunlight, the absorption of CO2 by plants enabled by nitrogen application to crops, and the breakdown of atmospheric methane by nitrogen oxides. However, the researchers caution that the benefits of nitrogen emissions in cooling the climate do not outweigh the harmful effects on health, biodiversity, and the ozone layer.

Professor Federico Maggi from the University of Sydney’s School of Civil Engineering emphasized that increasing atmospheric nitrogen as a means to combat climate change is not a viable solution due to its detrimental impacts. Similarly, Sönke Zaehle from the Max Planck Institute highlighted the importance of not overlooking the harmful effects of nitrogen emissions despite their cooling effect on the climate.

While elemental nitrogen is considered climate-neutral, other reactive nitrogen compounds can have both warming and cooling effects on the global climate. Nitrous oxide, for example, is nearly 300 times more potent as a greenhouse gas than CO2. The researchers stress the need for urgent action to reduce greenhouse gas emissions to mitigate the effects of climate change.

The study also underscores the importance of developing mathematical models to understand the complex interactions between nitrogen emissions, the global nitrogen cycle, and the carbon cycle. By analyzing the impact of nitrogen compounds on soil, water, and air, the researchers were able to assess the overall effect of human-generated nitrogen on radiative forcing, which influences the Earth’s energy balance.

In conclusion, the research highlights the intricate relationship between nitrogen emissions and climate change, emphasizing the need for immediate action to reduce greenhouse gas emissions and mitigate the harmful effects of nitrogen on the environment. The findings underscore the urgency of addressing climate change through comprehensive and sustainable measures.