Remedy 4: Evaluation of 3D averaging kernels for zenith-sky UV-visible ozone measurements

Primary gap remedy type: 
Secondary gap remedy type: 
Proposed remedy description: 

An evaluation of 3D averaging kernels for zenith-sky UV-visible twilight measurements based on AMF look-up tables is needed and a comparison with averaging kernels derived using a direct coupling of the retrieval with the output of a chemistry-transport model, in which the a priori profile used in the AMF calculation is replaced by a more realistic model-derived time and space dependent profile. To tackle this issue further, one or two specific retrieval algorithms coupled with chemistry-transport model output need to be selected to run an in-depth comparison with the averaging kernels retrieved based on the AMF LUTs. An important focus is that the averaging kernel calculated based on the AMF LUTs are representative enough to provide the information expected to add additional value to the actual measurements.


Many research groups are not setup to run their retrieval code coupled with a chemistry-transport model and so it is essential to have a less computationally demanding approach which can then be used much more widely. Hence it is vital to understand how the uncertainties increase using the method based on the look-up tables and how representative the vertical averaging kernel climatology is of real measurement conditions.

Measurable outcome of success: 

Including 3D averaging kernels for zenith-sky UV-visible ozone measurements in satellite and model validation studies should improve the agreement between the different data sets, especially for UV-visible stations located in winter/spring at the edge of the polar vortex where the spatial and temporal gradients of the ozone field can be very large.

Expected viability for the outcome of success: 
  • Medium
Scale of work: 
  • Single institution
  • Consortium
Time bound to remedy: 
  • Less than 3 years
Indicative cost estimate (investment): 
  • Low cost (< 1 million)
Indicative cost estimate (exploitation): 
  • No
Potential actors: 
  • EU H2020 funding
  • Copernicus funding
  • National funding agencies
  • ESA, EUMETSAT or other space agency
  • Academia, individual research institutes