What is the Monthly Average Atmospheric N₂O?

This is the average amount of nitrous oxide (N₂O) that is in the atmosphere in a given month. The monthly average highlights the seasonal variation. The graph shows the last 3 years to highlight the seasonal variation.

Nitrous oxide has a large warming effect, with a Global Warming Potential (GWP) that is 273 times greater than CO₂. Like CO₂, but unlike methane, it stays in the atmosphere for a long time, on average 116 years. Besides its warming potential, nitrous oxide is also important because it depletes the ozone layer, which protects us from the sun’s ultraviolet rays.

Units and measures

The primary unit here is parts per billion (ppb), which describes the average concentration of atmospheric methane per year. The secondary unit here is megatonnes, which describes the average weight of atmospheric methane per year. We show this to be able to relate to emissions, which are commonly expressed in megatonnes.

Insights from this chart

There is a light global seasonal cycle, with higher growth rates between October and March and less growth between April and September. Seasonal variation occurs both in the natural surface emissions and in the natural breakdown in the stratosphere.

About the data

The National Oceanic and Atmospheric Administration (NOAA) Global Monitoring Laboratory provides monthly atmospheric nitrous oxide data.

Data sources

Globally averaged marine surface monthly mean data ESRL's Global Monitoring Laboratory of the National Oceanic and Atmospheric Administration
Credits: Lan, X., K.W. Thoning, and E.J. Dlugokencky (2022): Trends in globally-averaged CH4, N2O, and SF6 determined from NOAA Global Monitoring Laboratory measurements. Version 2022-10, https://doi.org/10.15138/P8XG-AA10Update cycle: monthlyDelay: ~ 3 months