Nitrous oxide is a greenhouse gas. Other common names are laughing gas or happy gas. It contributes to the Earth’s greenhouse effect. Meaning that emissions of nitrous oxide lead to global warming. Most of the emissions come from the agricultural sector. Yet, nitrous oxide is also used in medical and dental procedures. Therefore, emissions from the healthcare sector are common as well.
Nitrous oxide is a very powerful greenhouse gas. In fact, when compared to carbon dioxide (CO2) it is much stronger. For example, 1 kg of the gas has the same warming effect as 300 kg of Co2.
Greenhouse gases contribute to the greenhouse effect, which leads to a warmer temperature on Earth. This is because the gases can capture the heat of the sun. They do this when the heat waves are on their way back out towards space again. In other words, as the heat waves from the sun hit the Earth, they are reflected through the albedo effect. When the waves are on their way back again, they are captured by the gases. In more scientific terms, the gases absorb long-wave heat radiation. The most important greenhouse gases are water vapour (H2O) and carbon dioxide (CO2). Then there is methane (CH4), nitrous oxide (N2O) and ozone (O3).
To measure how powerful greenhouse gases are there is the Global Warming Potential – GWP. The measurement compares a gas potential with CO2.
What is nitrous oxide?
Nitrous oxide is a colourless greenhouse gas that is released naturally and by human activities. Over 60 % of emissions come from natural processes. For example, from vegetation and the Earth’s soil or processes in the oceans. However, almost 40 % of emissions come from human activities. As mentioned, these are mainly from agriculture. One common source is the use of chemical fertilizers in the fields. Also, the gas is released in the burning of biomass and fossil fuels. As stated, there is also a small part of emissions coming from the healthcare sector.
The greenhouse can stay in the atmosphere for about 120 years. This means that it can keep contributing to global warming for a long time. The long lifetime lets the gas rise to higher levels in the atmosphere. Eventually, it reaches the stratosphere and decomposes into nitrogen oxides. These nitrogen oxides damage the ozone layer.
Therefore, emissions of nitrous oxide are harmful due to several reasons. Both as a powerful greenhouse gas, but also for the chain reactions that it can set in motion. Meaning that the gas can damage the ozone layer. Despite this fact, it is not regulated under the Montreal Protocol. Which is an international agreement to protect the ozone layer. As a result, the gas is one of the main threats to the layer today.