[MITgcm-devel] status

[Menemenlis, Dimitris (3248)]

Gael, Pierre and I just finished reviewing ice age tracer code together.
We have following questions and comments.

First, please confirm that by intensive and extensive you mean what is
called, respectively, actual and effective in pkg/seaice?

Second, regarding point (2) below, I think it is best left for when we
have a proper iTracer sub-package in place.

Third, regarding point (1) below, we were not able to find an
inconsistency in the way ice age is coded:

 1. for ifndef SEAICE_AGE_VOL, IceAge is always "effective" (or extensive).

 2. for ifdef SEAICE_AGE_VOL, IceAge is effective for advection, but
     briefly converted to "actual" (or intensive) in seaice_growth.F during
     the time-stepping of ice age and then converted back to effective.

Are we missing something?

Pierre et Dimitris

On Feb 24, 2011, at 1:01 AM, Gael Forget wrote:

> Hi Dimitris and Patrick,
> 
> a few thoughts regarding ice tracers (salinity and age for now). 
> 
> My recollection is that there are currently two issues regarding the age tracer:
> (1) it is advected as extensive, whereas it is otherwise treated as intensive.
> (2) the lack of detail regarding the effect of individual growth/melt terms on age.
> 
> With regard to generic ice tracers a choice will have to be made between 
> extensive (as in SEAICE_SALINITY) and intensive (as in SEAICE_AGE).
> I wrote down the two scenarios equations for Pierre so he knows how to 
> proceed either way for the age tracer. I dont have a strong preference but 
> 'intensive' would imply  a division by HEFF during advection (as opposed 
> to diagnostics) that could prove problematic. So I am wondering whether 
> it would it be good time to switch SEAICE_AGE to extensive. 
> 
> Cheers,
> Gael