Workshop on Modeling Chemistry in Cloud and Mesoscale Models

National Center for Atmospheric Research
Boulder, Colorado
6-8 March 2000 Many outstanding problems involving both the chemical and dynamical evolution of the atmosphere will soon be approachable using dynamical cloud- and meso-scale models coupled with chemistry models. The nonhydrostatic MM5 mesoscale model, which is widely used as the meteorological model for many chemistry transport models, is expected to be replaced by the Weather Research and Forecast (WRF) model. NCAR, NOAA/NCEP, NOAA/FSL, CAPS, and other participants, are collaboratively designing and constructing the WRF model, which in addition to replacing the MM5 model as the NCAR-supported community mesoscale model, will run operationally at NCEP for NWP, and will be used as a cloud model within the research community. Development of the model dynamical formulation, physical parameterizations and software architecture is underway, and now is the appropriate time to incorporate directly the needs of chemistry modeling into the WRF design.

PURPOSE:
To produce a community assessment of approaches and methodologies used for chemistry modeling in cloud and mesoscale models. Modeling issues that arise in coupled chemistry-dynamical models were analyzed so as to provide guidance for the development of the dynamical and chemistry components of the WRF model.

OUTCOME:
(1) A summary of the community consensus and understanding of the approaches, methodologies, parameterizations, and future development work.
(2) A guide for future model development.
(3) Guidelines for software development so that model coding efforts can be shared among different groups and modeling systems.

Workshop Summary

TOPICS were discussed with an expert on the topic introducing the subject and leading the discussion of state-of-the-art techniques and needed future research. The topics included (with links to overview talk abstracts):

- Dynamical Model Formulations                              W. Skamarock, NCAR
- PBL Parameterization                                             C. Hoh Moeng, NCAR
- Parameterized Deep and Shallow Convective Transport
                                                                                 G. Grell, NOAA/FSL
- Microphysics Parameterizations                              M. Barth, NCAR
- Coupling Chemistry with Clouds                             M. Barth, NCAR
- Chemical Mechanism Solver Techniques and Implementation of Mechanism
                                                                                  M. Jacobson, Stanford University
- Dry Deposition                                                       L. Ganzeveld, University of Utrecht
- Emissions                                                                C. Benkovitz, Brookhaven National Labs
- Radiation                                                                S. Madronich, NCAR
- Aerosols                                                                 F. Binkowski, EPA
- Long-Term Directions                                          P. Hess, NCAR

List of Attendees

Organizing Committee:
   Mary Barth
   Bill Skamarock
   Peter Hess
   Sasha Madronich