Question about default orbital parameters

[hayesdev]

Hello all,

I've been running some coupled lnd-atm simulations with a slab ocean and I've realized after running that I never explicitly set any orbital parameters for eccentricity and obliquity. I assumed they'd both default either to 0 or to earth-like values (~0 and 24°) but after some digging I've come to find that the default values are 1e36 when not set by the user in the user_nl_cpl namelist. I've run many simulations without setting the orbital parameters and I'd been assuming that these simulations had no seasonality before my discovery.

I have the following questions:

1. How are these default values interpreted by the model?
   1. Are these values actually used such that my obliquity and eccentricity are actually 1e36?
   2. Or is this number (1e36) used as a flag in the model code and some other value is used?
2. Does using default values result in a simulation with no seasonality like I assumed?
   1. Or would I need to run new simulations with eccentricity and obliquity explicitly set to 0 to achieve a simulation with no seasonality?

Any and all insight would be very helpful and appreciated!
Thanks

 

[slevis]

Others, please correct me if you disagree:
I would not worry about changing the default orbital parameters except for paleoclimate simulations. So certainly change orbital parameters when running for the Mid-Holocene or the Last Glacial Maximum or other paleo cases.

 

[slevis]

I realize that I did not answer your exact questions. I hope that others will be able to do so.