PhD position - "Smart preparation of air pollutant satellite retrievals for optimizing emissio

PhD position - "Smart preparation of air pollutant satellite retrievals for optimizing emission inventory data" within the HDS-LEE graduate school

Human activities—particularly increasing energy production and consumption, but also natural processes—release large quantities of trace substances, thereby influencing the composition of the atmosphere and the climate. Since the beginning of industrialization in the 19th century, the chemical composition of the air has changed significantly and today contains substantially higher levels of trace substances. This has two important consequences for the Earth system and human society:
On the one hand, trace substances influence the Earth’s radiation balance and climate; on the other hand, higher levels of pollution—particularly in the world’s industrialized countries and megacities—lead to health impacts, damage to ecosystems, and crop losses.

The Institute of Climate and Energy Systems - Troposphere (ICE-3) investigates the chemistry and transport of trace substances in the troposphere. To this end, field and simulation chamber experiments as well as model simulations are conducted. Our research in the “Atmospheric Modeling” division at ICE-3 aims to model and predict the composition of the atmosphere. The research focuses on multiphase processes, the role of tropospheric oxidants, and the role of pollutants in the gaseous and condensed phases on air quality.

It also investigates the extent to which observations are predictable and whether known emissions of air pollutants can explain the observed pollutant concentrations.

To make reliable predictions and analyses of air pollution, data assimilation methods, which integrate observational data into model simulation to update the model state and the underlying parameters, are inevitable. Specifically, the improvement of emission inventory data by data assimilation applications has demonstrated strong positive impact on the analysis’ performance. However, recent studies have demonstrated the limitations of current ground- and satellite-based observational networks.

The PhD project aims for a new method to derive ground-level concentrations from satellite-based measurements and additional data. Specifically, the project’s objective is to develop a data-driven method that maps satellite-derived data to ground-level concentrations for air pollutants such as NO2 (nitrogen dioxide), CO (carbon monoxide), and SO2 (sulfur dioxide). The methodology will be embedded into the data assimilation workflow of the European Air pollution Dispersion-Inverse Model (EURAD-IM).

Focus will be placed on the Sentinel-5P TROPOMI (Tropospheric Monitoring Instrument) data, which is available since 2018 and thus provides a big dataset. However, the transferability to Sentinel 4 and 5 data recently launched in July and August 2025 will be explored. All this has the potential to enhance the performance of emission data analyses to the next level.

The outcome of the project is twofold. Firstly, the project aims at developing a method that can derive ground-level concentrations of air pollutants on a high spatial resolution directly from satellite retrievals. Secondly, the outcome of this research will enable the sampling of satellite data to identify an optimal subset of observational data for optimizing the emission inventory data. Analyses of these emission corrections will be performed with the four-dimensional variational data assimilation (4D-var) system within the chemistry-transport-model EURAD-IM.

The simulation improvements due to optimized emission data will be evaluated with independent observations, such as vertical profile data from the In-service Aircraft for a Global Observing System (IAGOS).

The project will be conducted as a collaboration of the Air Quality and Emission Optimization group at the Institute of Climate and Energy systems (ICE-3) at Forschungszentrum Jülich and the group working on Methods for Model-based Development at RWTH Aachen. The PhD candidate will be based at Forschungszentrum Jülich where the scientific focus on atmospheric research is placed. To exchange and deepen the collaboration in…