CAM Development

CAM6 Development Activities

This page is intended to be a summary of the Atmosphere Model Working Group (AMWG) activities in developing the CESM Community Atmosphere Model version 6 (CAM6).

The path to CAM6 and CESM2

High horizontal resolution

We expect that global climate models in the next decade will run routinely at horizontal resolutions of 25 km or lower. High-resolution simulations targets simulations of tropical cyclones, improvement in important regional and mesoscale circulation, etc...

Increased Vertical resolution

Higher vertical resolution improves the ability to represent certain aspect of physics or dynamics better (QBO, sudden stratospheric warmings, ...

Cloud Physics

There are several Community development activities related to the improvement of the cloud physics (CLUBB, UNICON, deep convection activities).


Implement a multi-variate PDF based moist turbulence and cloud macrophysics scheme based on the Cloud Layers Unified By Binormals (CLUBB) into CAM.


A unified convection scheme for CAM that unifies treatment of deep and shallow convection.

Deep convection

Modifications of the Zhang McFarlane scheme for short-term tuning of CAM5 high resolution simulations.


Next generation of MG microphysics.
Includes prognostic precipitation, mixed phase ice nucleation and convective microphysics.

MG2 microphysics

New ice nucleation

Mixed-phase cloud ice nucleation + Refinement of ice nucleation treatment in cirrus clouds

Gravity Wave Drag (GWD) and Turbulent Mountain Stress (TMS)

Development targets Gravity Wave Drag (GWD) and Turbulent Mountain Stress (TMS) schemes.


MAM development

Development targets are MAM4 and prescribed MAM.
MAM4 includes a primary carbon mode and improves the simulation of black carbon at high-latitudes. 


Energy formulation in CAM

An error in the energy formulation in CAM is identified and corrected.


Ocean spunup issue in CESM

We look at spinup issue with the Spectral Element dycore


Spectral coupled simulation


CAM5-CLM4.5 coupled simulation


CAM development timelines

Bug reporting

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