From stationary Eddy covariance systems to mobile gas analyzer platforms: monitoring urban GHGs and air pollutants

Urban air pollution and greenhouse gas (GHG) emissions stem from diverse sources, including transportation, heating, buildings, waste management, industrial and agricultural activities, and natural events like forest fires. Simultaneous monitoring of air pollutants and GHGs with high selectivity and sensitivity is essential for resolving the complex chemical interactions and source–sink dynamics that characterize urban atmospheres. Accurate measurements across various spatial and temporal scales are essential for modeling and validating emission inventories or satellite observations.

Traditionally, solutions for monitoring air pollutants or GHGs with high precision and temporal resolution have been "one-gas-one-instrument", resulting in large, stationary setups with high energy consumption. MIRO Analytical’s compact laser absorption spectrometer that integrates multiple mid-IR lasers enables simultaneous high-precision measurements of greenhouse gases (CO₂, N₂O, H₂O, CH₄, C₂H₆), pollutants (CO, NO, NO₂, O₃, SO₂, NH₃), and trace gases (OCS, HONO, CH₂O) within a single instrument. With a time-resolution of up to 10Hz, it is well-suited for detecting the relationships between co-emitted pollutants and GHGs as well as eddy-covariance flux studies.

In this contribution, we showcase the broad variety of MIRO’s MGA analyzers for urban applications.
Thanks to their versatility, the same instrument can be used for: (I) Ambient air monitoring, demonstrated through a comparison campaign at a Zurich air-quality monitoring station, (II) urban eddy-covariance measurements, linking GHG fluxes to reactive gas emissions and improving the identification of emission sources and (III) airborne and van-based mobile measurements, enabling flexible deployment across urban environments. This unique multi-purpose approach provides insights that go beyond standard monitoring techniques and contributes to a deeper and more comprehensive understanding of the complex urban atmosphere.

Key words: eddy covariance, multi-compound gas analyzer, mobile monitoring, GHG fluxes, air pollutants