Impact of Spaceborne Observations on Tropospheric Composition Analysis and Forecast (ISOTROP)

The ISOTROP project, funded by ESA, estimates the impact of the European Copernicus Sentinel 4 and sentinel 5 & 5P satellite measurements of ozone, carbon monoxide, nitrogen dioxide and formaldehyde to quantify air pollution at high spatial resolution

The ISOTROP project aim is to quantify the impact of the European Sentinel 4 (GEO) and Sentinel 5/5P (LEO) measurements to better constrain pollutant concentrations and precursor emissions that influence air quality. ISOTROP studies space-borne observations of O3, CO, NO2 and HCHO. The project is based on a cross-OSSE (Observing System Simulation Experiment) approach which involves two independent air quality models. Each of the models generated a nature run for the other model, used subsequently in two linked OSSE studies. Synthetic satellite observations are computed from these nature runs and are assimilated by the other model. The models involved are MOCAGE (Meteo-France), and the air quality model LOTOS-EUROS (TNO/KNMI) combined with the global TM5 chemistry-transport model (KNMI) which are both run at high resolution (up to 7 km). The work is based on synthetic observations and their error characteristics derived by the KNMI and FMI teams involved in the TROPOMI retrieval algorithm development. Figure 1 contains an example of CO observations during one overpass of the S5P platform.

ISOTROP (Impact of Spaceborne Observations on Tropospheric Composition Analysis and Forecast) is an ESA funded study, ESA Contract No: 4000105743/11/NL/AF. Partner institutes are KNMI (Netherlands, Co-ordinator Henk Eskes), CNRS / Meteo-France (France), TNO (Netherlands), FMI (Finland) and NILU (Norway).

The project was finalised in winter 2017. The ISOTROP website provides access to the final report, the more detailed OSSE and synthetic observation reports, as well as a series of presentations and references.

C0 SP5
Example of (noisy) synthetic observations of CO for one overpass of the Sentinel 5P platform.