I am a physicist by training and started my scientific career in environmental physics at the University of Heidelberg, Germany, by analyzing alpine ice cores. I worked at the Max-Planck-Institutes for Meteorology, Hamburg, and for Biogeochemistry, Jena, both Germany for obtaining my PhD. Over the last 15 years I have been working in the field of Earth system science and data assimilation. Currently, I am Associate Professor for inverse modelling of the interaction between the atmosphere and the earth’s surface in the Department of Physical Geography and Ecosystem Science at Lund University, Sweden. My research focuses on the development and application of data assimilation methodologies to improve the quantification of the global carbon cycle with a focus on ecosystem-atmosphere interactions. I am one of the main developers of the Carbon Cycle Data Assimilation System (CCDAS), the first data assimilation system using, among others, atmospheric CO2 observations to optimize terrestrial ecosystem model process parameters. In the past, I have been active in AIMES by co-leading the AIMES Young Scholars Network. Besides being now a member of the AIMES SSC, I serve as an expert in the European Space Agency / European Commission CO2 Monitoring Task Forces to design an operational fossil fuel CO2 emissions monitoring system based on remotely sensed atmospheric CO2 concentrations. I am also a member of the Integrated Carbon Observation System (ICOS) carbon portal team. I have been involved in several European Commission and European Space Agency projects related to the global carbon cycle and data assimilation of Earth Observation data.