Global warming: Nitrous oxide traps 273 times more heat than carbon dioxide

By Yeter Ada Seko

ISTANBUL (AA) – Nitrous oxide, which is often overlooked in global warming discussions in comparison to carbon dioxide and methane, is responsible for its potent heat-trapping capability despite its smaller emissions share.

Except for carbon dioxide, Anadolu's second section on greenhouse gases focuses on nitrous oxide emissions and their sources. According to data from the Environmental Protection Agency (EPA), carbon dioxide constitutes 76% of greenhouse gases in the atmosphere, methane 16%, nitrous oxide 6%, and fluorinated gases 2% in the US.

Despite contributing a smaller share in total greenhouse gas emissions and being less discussed in global warming debates than carbon dioxide and methane, nitrous oxide garners attention for its notable heat-trapping capacity.

One ton of nitrous oxide traps 273 times more heat than one ton of carbon dioxide and can persist in the atmosphere for up to 110 years, compared to 10 years for methane, according to the National Aeronautics and Space Administration (NASA).

The study, titled Comprehensive Measurement of Global Nitrous Oxide Sources and Sinks, published in the journal Nature, revealed that the density of nitrous oxide in the atmosphere has increased by 20% over the past 150 years, reaching 331 ppb (parts per billion) from 270 ppb.

This increase has had an impact on both ozone layer depletion and global warming.

Nitrous oxide can be released from natural sources such as oceans and land, as well as directly or indirectly through human activities like agriculture, livestock, fossil fuel use, biomass burning, and wastewater.

While 60% of global nitrous oxide emissions occur through natural processes, 40% originate from human activities.

- Triggered by agricultural activities

World Bank data reveals that in 2020, human activities produced approximately 3 billion tons of carbon dioxide equivalents in nitrous oxide emissions.

Of this, 2.3 billion tons came from agriculture and livestock, while 276 million tons originated from activities in the energy sector.

Nitrous oxide emissions from human activities, especially with the widespread use of nitrogen in agriculture, are increasing.

The acceleration of agricultural activities in tandem with the increased demand for food due to a growing population leads to greater incorporation of fertilizers into the soil, contributing to nitrous oxide emissions.

The expansion of large-scale livestock farming and aquaculture to meet food demand is a significant contributor to the rise of nitrous oxide, as emissions from large livestock feces and grain cultivation used in their feed increase.

- Countries with highest emissions

China leads in total emissions with 536 million tons, followed by India with 279 million tons, the US with 258 million tons, Brazil with 191 million tons, and Indonesia with 75 million tons.

East Asia has the highest emissions, followed by North America in second place, Africa in third, and Europe in fourth.

The use of synthetic nitrogen fertilizers in agriculture, especially in East Asia, South Asia, and North America, is cited as a significant factor contributing to this pattern.

East Asia accounts for 71% to 79% of global nitrous oxide emissions from aquaculture, with South Asia and Southeast Asia contributing 10% to 20%.

- 'Oceans are a major nitrous oxide source'

Sam Wilson, professor of the faculty of natural and environmental sciences at Newcastle University in the UK, told Anadolu that discussions on climate change often center on energy production, transportation, and industrial processes, resulting in less attention to nitrous oxide compared to carbon dioxide.

Wilson observed that nitrous oxide is often associated with less visible agricultural and land use practices in the public eye.

He also highlighted that oceans are a significant source of nitrous oxide.

Wilson warns that rising ocean temperatures caused by global warming will increase ocean-sourced nitrous oxide emissions.

To reduce global nitrous oxide emissions, he suggests strategies such as reducing fertilizer use in agriculture, which can lead to nitrous oxide production and improving the efficiency of the nitrogen cycle in wastewater treatment plants, which are significant sources of gas.