Get Adobe Flash player

WG3: Chemical data assimilation in integrated model

The overall objective of WG3 is to establish the current state-of-the-science in this area and to provide a framework for the development of efficient techniques for chemical data assimilation in integrated models. Briefly, chemical data assimilation aims to improve model performance by modifying one or several components of the model (initial conditions, model inputs such as emissions, boundary conditions or some model parameters). Various mathematical techniques are used to assimilate the chemical observations and modify the model components, including variational techniques, ensemble or reduced-rank Kalman filters and other optimization techniques.

WG3 includes two tasks:

(1) Review the approaches currently used in chemical data assimilation, both in chemical-transport models and coupled chemistry meteorology models. The various aspects of chemical data assimilation will be considered, i.e., the model components being optimized (initial conditions, boundary conditions, emissions, model parameters) and the mathematical/numerical techniques available (4D-Var, ensemble Kalman filters, optimal interpolation, etc.). The pros and cons will be discussed. An important aspect that will be addressed will be multi-species chemical data assimilation for species that have chemical interactions. The pros and cons of various sources of chemical data (ground monitoring network, satellites, lidars, etc.) will be discussed.

(2) Identify priorities for the implementation of chemical data assimilation techniques with a focus on the development of operational tools for air quality forecasting. The practical aspects of chemical data assimilation and the research needs that are essential for the developments of effective techniques will be addressed.

Meeting minutes: