Nitrous Oxide Emissions

Free Nitrous Oxide Emissions calculator with clear step-by-step results.

About Nitrous Oxide Emissions

Nitrous oxide from managed soils is estimated from the nitrogen applied, not from the fertiliser mass. The IPCC default is that 1% of applied nitrogen is emitted as N₂O-nitrogen, and that figure must then be converted from nitrogen mass to N₂O mass by the molar ratio 44/28 — a step that is easy to miss and understates the answer by 57% if skipped. Indirect emissions from leaching, runoff and volatilised ammonia are added on top, then GWP converts the total to CO₂ equivalent.

Formulas

Nitrogen emitted as N₂O-N

Direct N₂O-N = nitrogen applied × EF1; indirect = direct × indirect share

Convert and weight

N₂O = N₂O-N × 44 ÷ 28; CO₂e = N₂O × GWP100

Worked example

With the default values below, Nitrous Oxide Emissions returns Warming Impact of 27.068. Change any input above and every figure here is recalculated in your browser.

Inputs used

Nitrogen appliedminimum 0 kg N: 5,000 kg N
Direct emission factor (EF1)accepts 0–0.2 kg N₂O-N/kg N: 0.01 kg N₂O-N/kg N
Indirect emissions (leaching and volatilisation)accepts 0–100 %: 30 %
Nitrous oxide GWP over 100 yearsminimum 1: 265

Results

Warming Impact: 27.068 t CO₂e
Total Nitrous Oxide Emitted: 102.143 kg N₂O
Direct Emissions: 78.571 kg N₂O
Indirect Emissions: 23.571 kg N₂O

Step by step

1Values used
2Nitrogen emitted as N₂O-N
3Convert and weight
4Warming Impact= 27.068 t CO₂e
5Total Nitrous Oxide Emitted= 102.143 kg N₂O
6Direct Emissions= 78.571 kg N₂O
7Indirect Emissions= 23.571 kg N₂O

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 3 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
Emission factors, indirect fractions and GWP values are prescribed by IPCC guidelines and national inventory methodologies, and vary with soil, climate and management. Use official country-specific factors for any regulatory or certified reporting.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Emission factors, indirect fractions and GWP values are prescribed by IPCC guidelines and national inventory methodologies, and vary with soil, climate and management. Use official country-specific factors for any regulatory or certified reporting.

Frequently Asked Questions

Why multiply by 44/28?

The emission factor is expressed as kilograms of nitrogen emitted in the form of N₂O. One N₂O molecule has a molar mass of 44 but contains 28 of nitrogen, so converting from N₂O-N to N₂O means multiplying by 44 ÷ 28 = 1.571.

What GWP should I use for N₂O?

265 in IPCC AR5 and 273 in AR6, with 298 in the older AR4. Nitrous oxide has an atmospheric lifetime of over a century, so unlike methane its 20- and 100-year values are close.

Why are indirect emissions so large a share?

Nitrogen that leaches into water or volatilises as ammonia is still nitrified and denitrified downstream, producing N₂O away from the field. IPCC defaults put this at roughly a quarter to a third of the direct amount.