Greenhouse Gasses: Nitrous Oxide (N2O)

Nitrous oxide: no laughing matter

nitrous oxide greenhouse gas

Much like carbon dioxide, nitrous oxide is beneficial in its naturally occurring state: it is found in soils, plants, animals and microorganisms, as well as the atmosphere. This nitrogen cycle is a crucial component for sustaining life on the planet.

Nitrous oxide is less abundant in the atmosphere than carbon dioxide (measured in parts per BILLION rather than parts per MILLION) but it is longer lasting (114 years vs carbon dioxide’s 20-200 years). Overall, nitrous oxide has 300 times more warming potential than carbon dioxide.  These qualities (pulled from the EPA on nitrous oxide) make it a potent and dangerous greenhouse gas. (See my post on carbon dioxide for refresher on greenhouse gasses.)

The concentration of nitrous oxide in the atmosphere has risen dramatically over the last century, from around 250 to 330 ppb in 2017; a 122% increase! And it is still rising!

atmospheric concentrations nitrous oxide

Where does it come from?

The increased emissions are clearly linked to human activities, contributing to the warming of the planet and subsequent climate crisis.

The majority of human caused nitrous oxide emissions are related to agricultural soil management:

U.S. nitrous oxide emissions
Sources of nitrous oxide emissions in the US, from the EPA report on nitrous oxide emissions

The specific agricultural practices that contribute to nitrous oxide emissions are:

  1. Overuse and misuse of synthetic nitrogen-based fertilizers
  2. Organic fertilizers
  3. Nitrogen-fixing crops
  4. Some irrigation practices, including draining peat bogs for cropland

While the Industrial Revolution caused massive carbon dioxide emissions, the Green Revolution caused the increased nitrous oxide emissions: in the mid-1900s, developed nations introduced “western-style” agricultural practices to developing nations. The world hailed the Green Revolution as a necessary step to feed the world’s ever-increasing population. It came with a hidden cost.

From the Columbia University Earth institute article Agriculture and its Discontents: Greenhouse Gas Emissions, the Green Revolution model “requires heavy irrigation, intensive inputs of chemical fertilizers and pesticides, and large-scale monocultures (single-crop farms), with accompanying hypoxic zones in the seas, increased deforestation, and an increase in greenhouse gas emissions.

So what is stopping us from fixing our agricultural practices?

It seems pretty easy: just fix the way we manage agricultural soils, right? Unfortunately, the powerful and influential Farm Bureau (a farm lobby) is an active advocate for and partner with the fossil fuel industry.

There is a lot of money in maintaining the current agricultural system: U.S. agriculture and related industries are worth nearly one trillion dollars, and the U.S. government pays $13 billion in subsidies annually.

there is HOPE

We know which practices need to be changed, and we have lots of alternatives. With some good tools for measuring emissions and a focus on sustainable farming practices, emissions from this particular greenhouse gas could be reduced significantly.

take action

Direct action to reduce nitrous oxide emissions is really about choices around food and voting.

Recent studies have confirmed that organic farming has lower N2O emissions than conventional, "modern" farming; choosing organic can make a difference, as can choosing locally grown. 
Eating less meat, without going completely vegan or vegetarian, has significant impacts on emissions of nitrous oxide, carbon dioxide, and methane, as well as slows deforestation for cattle pasture. 
As with all facets of tackling climate change, the most crucial is having elected officials who understand the emergency and the limited time we have. Electing officials who support national initiatives like the Green New Deal and local work such as declaring a climate emergency (as did New York, Miami, London, L.A.) is critical to get us moving in the correct direction quickly.

The Sunrise Movement has a 2020 Presidential Candidate Scorecard. The Environmental Voter Project simply encourages people who care about the environment to vote. 

Make sure you are registered to vote, and pay attention to what the candidates are saying about the climate emergency.