CCWG | Chemistry Climate Working Group

The goal of the Chemistry-Climate WG is to continue the development of the representation of chemical gas and aerosol species in the CESM and to further our understanding of the interactions between chemistry/aerosol and climate. Scientific motivations include advancing knowledge on past, present and future atmospheric composition, interactions between atmospheric composition and the Earth System, stratosphere-troposphere coupling, aerosol direct and indirect effects on the Earth's energy balance, aerosol effects on precipitation, and impacts of global chemistry/aerosol and climate on air quality.

The chemistry and aerosol schemes are now fully incorporated into the CESM, e.g. options for super-fast chemistry, full troposphere chemistry, troposphere and stratosphere chemistry, bulk aerosol, and modal aerosols that fully interact with the clouds and radiation. CAM-chem was used extensively to perform 1850-2100 (all RCPs) simulations to define atmospheric composition (and deposition fields) for use in CCSM4.

CAM-chem can also be run as an offline version (specified dynamics, SD) using GEOS5 and MERRA meteorological fields so as to simulate specific dates.

Topics of Development and Research

Testing the representation of chemistry and aerosols in CESM and evaluating existing and forthcoming CAM configurations, see Development Plans. These configurations include:

  1. CAM5 physics, especially the coupling of interactive gas-phase chemistry and the modal aerosols and the impact of the new planetary-boundary layer parameterization.
  2. Improved modeling capabilities for new chemistry to allow for better process understanding. Current applications include isoprene oxidation mechanisms and tropospheric halogen chemistry.
  3. Improved modeling capabilities for different dynamical cores and horizontal resolutions.

Support Forum

Support for running CESM is available on the DiscussCESM bulletin board, where users can request assistance with science and runtime issues. The bulletin board includes a CCWG support forum section.

The announcements section of the forum contains guides of general use to CCWG users, including:

Detailed instruction on how to run CESM with chemistry can be found here: Community & User Support.

CCWG Liaison Information

CCWG Co-Chair Information

Dr. Xiaohong Liu
3/1/2016 - 2/28/2020
University of Wyoming, Department of Atmospheric Science, Dept. 3038 - 1000 E. University Ave., Laramie, WY 82071

Dr. Louisa Emmons
2/10/2014 - 12/31/2019
NCAR-ACD, P.O. Box 3000, Boulder, CO 80307-3000