Synthetic Sentinel-4 NO2 data processing

This chapter describes the tasks performed for processing a set of synthetic Sentinel-4 NO2 data.

Product description

The Sentinel-4 mission includes instruments that observe trace gasses over Europe from a geo-stationairy orbit. The intended lauch in in 2023.

Sentinel-4 mission

Artist impression of Sentinel-4 at geo-stationary position observing Europe. Shaded area on the right shows extent of the domain used by CAMS Regional Ensemble, which for a large part overlaps with the Sentinel-4 Geographic Coverage Area (GCA).

The Sentinel-4 instrument will provide at daytime hourly snapshots of trace gasses at a resolution of about 8x8 km. The amount of data values is therefore much higher than for the polar orbiting Sentinel-5p instrument. In the context of the CAMS_61 project, a first evaluation has been made of the resources needed to process the future Sentinel-4 data within simulation models. For this, a synthetic data set of Sentinel-4/NO2 data has been created using simulations from the MONARCH model (BSC), accompanied with realistic error characteristics and averaging kernels produced using machine-learning. An extensive description of how the data was produced and evaulated is available in:

  • Final report of WP6130 R&D activities (not available online yet)

Synthetic Sentinel-4 NO2

Example of synthetic Sentinel-4 NO2 retrievals.

Downloading

The data set be available through a public server.

The data set consists of hourly files for July 2018:

S4_v3_r/BSC_S4-syn_NO2_20180701_0000.nc
        BSC_S4-syn_NO2_20180701_0100.nc
        BSC_S4-syn_NO2_20180701_0200.nc
                                 :
        listing.csv

Also a listing file is included for use with the CSO observation operator.

A catalogue of images of the data could be made similar to the S5p NO2 image catalogue.

Configuration of observation operator

The observation operator described in chapter ‘Observation operator’ requires settings from an rcfile. Template settings are included as:

oper/tutorial_oper_S4-syn.rc

The tutorial program tutorial_oper_S5p.F90 should be changed to use these settings rather than the default settings:

!~ input settings for synthetic S4/NO2
rcfile = 'tutorial_oper_S4-syn.rc'
! base of keywords in rcfile:
rcbase = 'tutorial.S4-syn.no2'

Without further changes, the tutorial program will create (dummy) simulations of the synthetic Sentinel-4 retrievals.

A catalogue of images of the, by the tutorial, simulated data could be made similar to the simulated S5p NO2 image catalogue.