This research initiative is divided into two activities, collectively having three goals:
- To define the current state of the science with respect to representations of wet and especially dry deposition in regional models
- To quantify the extent to which different dry deposition parameterizations influence retrospective air pollutant concentration and flux predictions
- To identify, through the use of a common set of detailed diagnostics, sensitivity simulations, model evaluation, and reduction of input uncertainty, the specific causes for the current range of these predictions.
Activity 1 is dedicated to the diagnostic evaluation of wet and dry deposition processes in regional air quality models (described in this paper).
Activity 2 to the evaluation of dry deposition point models against ozone flux measurements at multiple towers with multiyear observations (to be described in future submissions as part of the special issue on AQMEII4).