Model:WACCM-EE

WACCM-EE

Model type:	Model
Description:	I am developing a GCM based on NCAR's WACCM model to studied the climate of the ancient Earth. WACCM has been linked with a microphysical model (CARMA). Some important issues to be examined are the climate of the ancient Earth in light of the faint young Sun, reducing chemistry of the early atmosphere, and the production and radiative forcing of Titan-like photochemical hazes that likely enshrouded the Earth at this time.

Supported platforms:	Unix, Linux, Mac OSX,
Programming language:	Fortran77, Fortran90
Model was developed started from:	2008 and is still going on
To what degree will the model become available:	As source code
Current license type:	GPLv2
Memory requirements:	1GB for input data
Typical run time:	1.5 days per model year on 8 processor mac

Input parameters:	GCM initial conditions files (netcdf) files describe initial state of atmosphere up ~km 140
Input format:	netcdf
Output parameters:	netcdf output files describing atmospheric state, chemistry, etc
Output format:	Netcdf
Post-processing software (if needed):	IDL igeov viewer (IDL procedure)
Visualization software (if needed):	IDL

Processes represented by model:	General circulation model of early Earth. Particular detail is paid to chemistry, RT, and haze microphysics
Key physical parameters & equations:	Equations focused on are the radiative transfer equations, and equations governing haze microphysics
Length scale & resolution constraints:	Currently, 4x5 degree, with 66 vertical levels up to 140 km. Resolution can be increased if neccessary
Time scale & resolution constraints:	The model takes about 4-6 model years to reach equilibrium. The modeled time period is from the Archean Earth (3.8 - 2.5 Ga)
Numerical limitations and issues :	Dynamics, chemistry, RT, microphysical, and slab ocean model are all coupled, thus the model runs slowly.

Available calibration data sets:	Haze microphysics can be checked against Bardeen 2008 for initial accuracy.
Available test data sets:	I have numerous data sets produced by an 8 processor Mac and a local unix cluster to confirm the model is initialized correctly.
Ideal data for testing:	Cassini data describing Titan photochemical haze. Laboratory work constraining haze properties.

Currently or plans for collaborating with:	Yes, I plan on collaborating with others in particular when it comes time to rework the model chemistry modules.

Comments:	The Early earth haze microphysical code is working, incorporating fractal particle structures. Development is needed on linking microphysics to RT.