Research Group Chemical Data Assimilation
Head: PD Dr. H. Elbern
How can observations, models, remote sensing data, and statistical knowledge be combined to find an optimal estimate of the chemical state of the atmosphere, emission sources, or further parameters? How precise can these parameter estimates or forecasts be?
The Chemical Data Assimilation group (CDA) conducts cutting edge research on the development and use of advanced data assimilation algorithms, which allow to address these questions.
Chemical data assimilation seeks to combine numerical atmospheric chemistry simulations with observations in a mathematically rigorous way to either produce an optimal chemical state estimate or indicate a systematic inconsistency of modelling with observation, signalling a significant gap in our understanding of the chemical regime. The chemical data assimilation group at RIU contributed to the development of this research area with pioneering studies on the four-dimensional variational method (4D-var) since the mid-nineties (e.g. Elbern et al., 1997; 1999, 2001, 2007).
Applications of the data assimilation and inversion algorithms serve our involvements in both
- pre-operational GMES (Global Monitoring for Environment and Security) services, for example the EC FP 7 projects MACC II and PASODOBLE, and
- scientific field campaigns, for example the EC FP7 project PEGASOS.
Either objectives serve to understand atmospheric chemistry and air pollution, including aerosols, which helps us to monitor and forecast chemical weather and the radiative impact on climate.
The group’s assimilation based analyses and forecasts serve several international field campaigns (e.g. PEGASOS) and is leading the development of advanced numerical models of chemistry data assimilation in MACC II. In this realm, our assimilation system is based on the EURopean Air pollution Dispersion - Inverse Model (EURAD-IM) including its tangent-linear and adjoint derivatives.
Our research and development interests also extend into assimilation of the chemistry of the stratosphere and lower mesosphere. Here, the 4D-var data assimilation system SACADA (Synoptic Analyses of chemical Constituents by Advanced Data Assimilation) has been developed, which is routinely operated at the World Data Centre for Remote Sensing at DLR.
We collaborate closely with atmospheric chemistry groups in the Institute of Energy and Climate research 8 (troposphere) at Research Centre Jülich.
Contact person: Hendrik Elbern (Staff)