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Research Programme
Satellite Instruments
Methods & Tools
Local Weather
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Satellite Observations of Air Quality



Ammonia (NH3) and carbon monoxide (CO) are important atmospheric pollutants, contributing to the production of ozone and particulates, which are important to air quality and also to climate change. Ammonia is generated from agricultural processes and carbon monoxide from fossil fuel combustion, but both are also products of biomass burning.

Concentrations of these (and many other molecules) can be retrieved from their infrared signatures in the spectra taken by the current generation of polar-orbiting interferometers, such as the IASI instrument on the MetOp satellites.

Aims of the Project

Both RAL (CO) and Oxford (NH3) have developed retrieval algorithms for IASI and the first part of the project will be to compare these results with other sources, eg other IASI retrievals, other satellite instruments, models, and surface measurements.

The second part of the project involves the adaptation of these algorithms for two new satellite instruments:

  • IASI-NG, the next generation IASI instruments, the first of which will be launched in 2021 and should provide data in the time-frame of the DPhil. This will have improved spectral resolution, allowing more species to be retrieved and with greater accuracy.
  • MTG-S, the third generation of the Meteosat geostationary satellite which will carry an interferometer viewing the entire earth's disk every hour. The first of these is due for launch in 2023. Unlike the IASI instruments which are on polar-orbiters and hence view each location only every 12 hours, the MTG-S will allow the full diurnal cycle to be observed.

Global map of CO concentrations on 13 Aug 2018 retrieved by RAL from infrared spectra taken by the IASI instrument on the MetOp-A satellite. Note the high concentrations associated with pollution events, including the Canadian wildfires. The white areas represent gaps in the IASI coverage between orbits.

Relevant Skills

Ability to write computer code in Fortran, C, IDL or Python, basic knowledge of radiative transfer and inverse methods.
Earth Observation Data Group, Department of Physics, University of Oxford. Page last updated: @12:46 GMT 20-Aug-2021