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 are now fully incorporated into the CESM, e.g. Options for super-fast chemistry, full troposphere chemistry, bulk aerosol, and modal aerosol that fully interact with the clouds and radiation. CAM was used extensively to perform 1850-2100 (all RCPs) simulations to define atmospheric composition (and deposition fields) for use in CCSM4. CAM can also be run as an offline version using GEOS5 and MERRA data to support aircraft campaigns and other observations and with stratospheric chemistry.
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:
- CAM5 physics, especially the coupling of interactive gas-phase chemistry and the modal aerosols and the impact of the new planetary-boundary layer.
- Improved modeling capabilities for new chemistry to allow for better process understanding. Current applications include isoprene oxidation mechanisms and tropospheric halogen chemistry.
- Improved modelling capabilities for different dynamical cores and horizontal resolutions.
Support for running CESM is available on the DiscussCESM bulletin board
, where users request assistance with science and runtime issues. The bulletin board includes a CCWG support forum
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.