millennium simulations

[andres]

Hello.

I am putting together input datasets for a millennium simulation using CCSM3.0, and I have a few questions.

1) I have looked through the source code, and it appears that there is no way to specify a transient orbital forcing. Is that correct?

2) I have a volcanic dataset that is in units of atmospheric optical depth. MY understanding from the code is that I must provide the volcanic forcing in terms of the volcanic aerosol mass per bin. Is there a way I can use optical depth instead, or is there a reference to a method of extracting volcanic mass from the optical depth?

I'd be grateful for any suggestions. Thank-you.
H. Andres