This letter provides an overview of the available measurement techniques for nitrous oxide (N2O)
flux measurement. It is presented to aid the choice of the most appropriate methods for different
situations. Nitrous oxide is a very potent greenhouse gas; the effect of 1 kg of N2O is estimated to
be equivalent to 300 kg of CO2. Emissions of N2O from the soil have a larger uncertainty
compared to other greenhouse gases. Important reasons for this are low atmospheric concentration
levels and enormous spatial and temporal variability. Traditionally such small increases are
measured by chambers and analyzed by gas chromatography. Spatial and temporal resolution is
poor, but costs are low. To detect emissions at the field scale and high temporal resolution,
differences at tens of ppt levels need to be resolved. Reliable instruments are now available to
measure N2O by a range of micrometeorological methods, but at high financial cost. Although
chambers are effective in identifying processes and treatment effects and mitigation, the future lies
with the more versatile high frequency and high sensitivity sensors
