Nitrous oxide emissions from a municipal landfill

Area of Science:

• Environmental Science
• Atmospheric Chemistry
• Geochemistry

Background:

• Landfills are significant sources of greenhouse gases.
• Accurate measurement of nitrous oxide (N2O) emissions from landfills is crucial for climate change mitigation.
• Limited data exists on N2O emissions from landfills, particularly using advanced measurement techniques.

Purpose of the Study:

• To report the first measurements of N2O emissions from a landfill using the eddy covariance method.
• To compare eddy covariance measurements with traditional enclosure methods for N2O emissions.
• To assess the contribution of landfill N2O emissions to overall greenhouse gas emissions.

Main Methods:

• Utilized the eddy covariance technique for continuous measurement of N2O fluxes.
• Employed the enclosure method for comparative emission measurements at the same landfill site.
• Analyzed N2O emission data in milligrams of nitrogen per square meter per hour (mg N m(-2) h(-1)).

Main Results:

• Average N2O emissions were 2.7 mg N m(-2) h(-1) (eddy covariance) and 6.0 mg N m(-2) h(-1) (enclosure).
• Landfill N2O emissions are 1-2 orders of magnitude higher than those from Northern European agricultural and boreal forest soils.
• N2O emissions constitute approximately 3% of the landfill's total greenhouse warming potential (GWP100).

Conclusions:

• Eddy covariance and enclosure methods provide comparable N2O emission estimates from landfills.
• While landfill N2O emissions are high per unit area, their overall impact on national emissions is minor due to limited landfill surface area.
• N2O emissions from landfills represent a notable, yet manageable, component of their total greenhouse gas contribution.